Inferior Progression-free Survival Research Articles

A CD5 Gene Signature Identifies Diffuse Large B-Cell Lymphomas Sensitive to Brutonʼs Tyrosine Kinase Inhibition

Introduction: Diffuse large B-cell lymphomas (DLBCLs) with a non-germinal center B cell-like (non-GCB) cell-of-origin are frequently driven by genetic alterations that culminate in constitutive B-cell receptor (BCR) signaling, which has inspired the exploration of Bruton's tyrosine kinase inhibitors (BTKi) in these lymphomas. However, the phase III PHOENIX study that randomized untreated, non-GCB DLBCL patients to R-CHOP plus placebo or ibrutinib failed to meet its primary endpoint of event-free survival (Younes et al. 2019), which suggests that cell-of-origin alone is an insufficient biomarker to predict BTKi sensitivity in DLBCL. More recently, a DLBCL genetic classifier termed LymphGen has identified distinct subtypes (MCD and N1) of non-GCB DLBCL that benefit from the addition of BTKi to R-CHOP (Wilson et al. 2021). However, genetic classifiers are complex and difficult to implement in routine clinical settings and may fail to capture all DLBCLs that benefit from BTKi. Therefore, we sought to identify a straightforward biomarker of BTKi responsiveness in DLBCL with greater precision than cell-of-origin but with broader inclusivity than current genomic platforms, such as LymphGen. We hypothesized that CD5 - a surrogate marker of BCR activation - may effectively identify BCR-driven, non-GCB DLBCLs that are sensitive to BTKi therapy, and evaluated the extent to which CD5 protein expression and a transcriptionally defined CD5 gene signature could accurately identify BCR-activated DLBCLs with potential susceptibility to BTKi-based therapies. Methods: CD5 immunohistochemistry (IHC) was performed on a cohort of 406 diagnostic DLBCL samples, which were considered CD5+ if >=30% of lymphoma cells exhibited unequivocal membranous staining. A majority of DLBCL samples had available RNA-sequencing and targeted mutational sequencing data. A comparison of differentially expressed genes between CD5+ and CD5- DLBCLs was performed in order to construct a 60-gene CD5 signature (CD5sig), which was applied to large genomic DLBCL datasets, including pre-treatment biopsies from patients enrolled on PHOENIX (n = 584) to evaluate the utility of the CD5sig in identifying DLBCLs that benefitted from the addition of ibrutinib to R-CHOP. Results: Twenty-six of 406 DLBCLs were identified as CD5+ by IHC (6% of all DLBCLs; 12% of non-GCB DLBCLs). CD5 IHC+ DLBCLs were majority non-GCB cell-of-origin and were associated with inferior progression-free survival (PFS) to R-CHOP (50% 3-year PFS), compared with CD5 IHC- DLBCLs, consistent with previous reports. Gene set enrichment analysis revealed that CD5 IHC+ DLBCLs exhibited transcriptional features of BCR activation, and mutational analysis demonstrated that CD5 IHC+ DLBCLs were enriched for CD79B BCR-activating mutations known to correlate with BTKi sensitivity. Many CD5 IHC+ DLBCLs, however, lacked canonical BCR-activating mutations or were classified as “Other” by LymphGen. A CD5 gene signature (CD5sig; Figure 1A) was developed that recapitulated these findings in independent DLBCL datasets (NCI, Duke), where ~13% of non-GCB DLBCLs were classified as CD5sig+. Together, these results suggest that CD5 signature expression captures DLBCLs with both a genetic and non-genetic basis for BCR dependence. Supporting this notion, CD5sig+ DLBCL patients (< 60 years) derived a selective and striking event-free and overall survival advantage from the addition of ibrutinib to R-CHOP in the PHOENIX study ( Figure 1B), independent of LymphGen classification. Conclusions: We demonstrate that CD5 IHC and a novel CD5 gene signature identify high-risk, BCR-driven DLBCLs. Importantly, the CD5 signature also identifies DLBCL patients with a selective survival advantage to BTK inhibitor-based therapy, independent of LymphGen classification. In conclusion, the CD5 signature expands upon LymphGen classification as a biomarker of BTKi response by accurately identifying DLBCLs with both genetic and non-genetic bases for BTKi response. The CD5 signature and/or CD5 IHC should be prospectively evaluated in BTKi-based clinical trials for non-GCB DLBCLs.

TP53 Mutations Detected By Clinical Laboratory Mutation Analysis Predict for Inferior Clinical Outcomes in Patients with Newly-Diagnosed Aggressive B Cell Lymphomas, Including Those with High-Risk Features

Introduction While comprehensive genomic analyses have identified genetic subgroups of diffuse large B cell lymphoma (DLBCL) when retrospectively performed on tumor biopsies (bx) from patients (pts) subsequently treated with R-CHOP (PMID 29713087, 29641966), it is unclear if these or similar assays can be applied in clinical practice. We aimed to determine if mutations (mut) detected in bx from newly-diagnosed DLBCL/high grade B cell lymphoma (HGBL) pts by clinical laboratory mutation analysis (CLMA) could predict for clinical outcomes following receipt of first-line therapy. Methods Pts with newly-diagnosed DLBCL/HGBL from January 2018-June 2022 whose bx underwent CLMA at the Penn Center for Personalized Diagnostics and received standard-dose R-CHOP or R-EPOCH as first-line therapy were included. Exclusion criteria were death due to non-lymphoma causes during first-line therapy and follow-up <1y after diagnosis if in remission. Pathologic workup of bx was performed as per institutional standard. Therapy was given at the discretion of the treating physician. Data were censored on July 1, 2023. Results One hundred thirty-seven pts met inclusion criteria, 15 were subsequently excluded and 117/122 pt bx underwent successful performance of CLMA (96%) with a median turnaround time of 17 days. Baseline characteristics, including mut occurring in ≥10% of cases tested, as well as genetic subgroup classification by LymphGen 2.0 based on available molecular data, are listed in the Table. R-CHOP was received by 72% of pts and R-EPOCH 38% of pts. The overall response rate (ORR) was 84% (complete response rate [CRR] 69%), and with a median follow-up of 31.3 months, estimated (est) 2 year (y) progression free survival (PFS), est 2y overall survival (OS) and est median OS post-relapse were 70%, 83% and 21.4 months (mo), respectively. Univariate analysis (UVA) identified HGBL classification, MYC rearrangement (R) and TP53 mut as significantly predictive of progression at 2y; however, only TP53 mut remained predictive on multivariate analysis (MVA) (HR 2.3, 95% CI 1.1-4.8, P=0.03). Additionally, UVA identified International Prognostic Index (IPI) score ≥3, HGBL classification, MYC-R, MYC-BCL2 double hit lymphoma, TP53 mut and TNFRSF14 mut as significantly predictive of death at 2y; however, only HGBL classification (HR 5.0, 95% CI 1.1-22.7, P=0.04) and MYC-R (HR 4.4, 95% CI 1.0-18.0, P=0.04) remained predictive on MVA. Given that TP53 mut predicted for both progression and death at 2y, we further analyzed bx with this mut. Forty-seven TP53 mut were detected in 42 pt bx, and were characterized as missense (mis) in 34, frameshift (fs) in 5, nonsense (non) in 5 splice site (ss) in 2 and other in 1. Thirty-eight (81%) TP53 mut were deemed loss of function (LOF), either as a mis/non mut designated as non-functional and/or LOF through The TP53 Database (https://tp53.isb-cgc.org/) or a fs/ss mut (PMID 22955915). Characteristics of pts with and without TP53 mut are listed in the Table. Significantly lower rates of ORR (71% vs 90%, P=0.009), CRR (55% vs 77%, P=0.01), est 2y PFS (57% vs 77%, P=0.006), est 2y OS (70% vs 91%, P=0.001) and est median OS post-relapse (6.1 mo vs not yet reached, P=0.001) were achieved by pts with vs without any TP53 mut. Est 2y PFS was 70% vs 33% ( P=0.01) and 2y OS was 85% vs 43% ( P=0.001) for pts with any TP53 mut treated with R-CHOP vs R-EPOCH. Additional analysis incorporating LOF status for TP53 mut revealed that for pts with at least one TP53 LOF mut vs only TP53 non-LOF mut vs no TP53 mut, 2y PFS was 51% vs 86% vs 77% ( P=0.002) as depicted in the Figure and 2y OS was 64% vs 100% vs 91% ( P=0.0004), respectively. Finally, stratified log-rank demonstrated either inferior or a trend towards inferior 2y PFS for pts with vs without TP53 LOF mut harboring high-risk features, including IPI score ≥3 (42% vs 80%, P=0.009), HGBL histology (25% vs 70%, P=0.046), non-GCB cell of origin by Hans algorithm (52% vs 81%, P=0.01), MYC rearrangement (33% vs 48%, P=0.17), MYC-BCL2 double hit lymphoma (40% vs 67%, P=0.34) and EZB genetic subgroup (30% vs 81%, P=0.04). Conclusions TP53 mut identified through CLMA, specifically those resulting in LOF, predict for inferior clinical outcomes in pts with newly-diagnosed DLBCL/HGBL. Results of CLMA can be practically used to inform prognosis and/or identify pts for clinical trials investigating therapies targeting derangements caused by specificmut.

The Prognostic Value of Dynamic Change of NK-Cell Counts in Diffuse Large B-Cell Lymphoma Treated with R-CHOP

Key words: Diffuse large B-cell lymphoma, Natural killer cell count, prognosis. Introduction Natural killer (NK) cell counts at diagnosis have been reported to be associated with poor outcomes, but the dynamic change and prognostic value of NK cell counts after treatment in diffuse large B-cell lymphoma (DLBCL)remain unknown. NK cell count was test by flow cytometry at diagnosis, interim and the end of treatment. Receiver operating characteristic (ROC) curve was used to determine the best cutoff value for survival analysis. Overall survival (OS) and progression-free survival (PFS) were analyzed by the method of Kaplan-Meier and Cox proportional hazard regression model. A total of 175 DLBCL patients were analyzed and 45 of them were divided into the low NK cell counts with the cut-off value was 94.5/ul. Patients with low NK cell counts were associated with B symptoms (p < 0.001), high LDH (p=0.002), advanced stage (p < 0.001) and high IPI scores (p=0.001). Survival analysis showed patients with low NK cell counts at diagnosis showed more inferior OS and PFS than those with high NK cell counts (p < 0.001 and p < 0.001). There were 60 patients showed low NK cell counts at the interim, consist of 31patients with low and 29 with high NK cell counts at diagnosis and 65 patients had low NK cell counts at the end of the treatment, consist of 31patients with low and 34 with high NK cell counts at diagnosis. But NK cell count at the interim or end of treatment had no impact on the PFS (p = 0.415 and p = 0.011) and OS (p = 0.537 and p = 0.836) of DLBCL patients. Multivariable analysis revealed that NK cell counts was an independent prognostic factor OS [relative risk (RR);95% confidence interval (CI),0.157-0.984, p = 0.046] and PFS (RR,0.335;95%CI,0.191-0.588, p < 0.001） in all DLBCL patients independent of IPI. In conclusion, low NK cell counts at diagnosis is a simple and effective adverse prognostic factor in DLBCL patients treated with R-CHOP. However, the NK cell counts at the interim and the end of the treatment showed no impact on outcome.

Impact of Genetic Mutations on Survival Following Receipt of Commercial CART19 for Patients Diagnosed with Aggressive B Cell Lymphoma

Introduction Anti-CD19 chimeric antigen receptor-modified T cell therapies (CART19) have revolutionized treatment of patients (pts) with relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL) and high grade B cell lymphoma (HGBL). However, progression of disease following receipt of CART19 is common with only approximately one-third of pts achieving long-term remission in the standard-of-care setting (Transplant Cell Ther. 2022 Sep;28(9):581.e1-581.e8, Blood (2022) 140 (Supplement 1): 1584-1587). While loss of CD19 antigen expression antigen is one mechanism of CART19 failure, other tumor-intrinsic factors which may result in CART19 failure remain poorly defined. Clinical laboratory mutation analysis (CLMA) performed on tumor specimens can identify recurring genetic mutations which may predict for clinical outcomes; however, the predictive value of CMLA has not been well-established for DLBCL/HGBL pts treated with CART19. Here, we analyze the impact of genetic mutations as detected by CLMA, along with other clinicopathologic characteristics, on survival outcomes of DLBCL/HGBL pts following receipt of CART19. Methods We collected data from 46 pts with DLBCL or HGBL treated at the University of Pennsylvania between 2018 and 2021. Patient tumors were sequenced with one of three sequencing panels comprised of 41-116 genes prior to receiving commercial CART19. Cox proportional hazards regression was used to assess the impact of clinicopathologic characteristics on disease progression and death, with characteristics demonstrating p <0.10 on univariate analysis included in multivariate analysis. Estimated progression free survival (PFS) and overall survival (OS) from the time of CART19 infusion were calculated using Kaplan-Meier estimates. Results Baseline clinicopathologic characteristics are listed in Table 1. A total of 30 of 46 pts had at least one tumor mutation detected prior to receiving CART19, with 22 genes mutated in at least two pts (Figure 1). The most frequent mutations were TP53 (15 of 46, 32.7%), BCL2 (3 of 12, 25%), MYC (4 of 20, 20%), SOCS1 (5 of 38, 13.2%), CD79B (5 of 38, 13.2%), CREBBP (5 of 38, 13.2%), EZH2 (5 of 46, 10.9%), STAT3 (4 of 38, 10.5%), TNFRSF14 (4 of 38, 10.5%) and DNMT3A (2 of 20, 10%). The median length of follow-up from the time of CART19 infusion was 29.6 months. For all pts, the rates of 2 year (y) PFS and OS were 21% (95% confidence interval [CI] 10-34%) and 56% (95% CI 40-69%), respectively. Univariate analysis of mutations present in ≥10% of cases revealed that TNFRSF14 mutations predicted for lower risk of disease progression at 2y (HR 0.16, 95% CI 0.02-1.186, p = 0.07). No other mutation was associated with either disease progression or death at 2y. Univariate analysis of baseline clinicopathologic characteristics also identified International Prognostic Index (IPI) score ≥3 at the time of relapse preceding CART19, HGBL classification, no history of indolent lymphoma (IL), MYC rearrangement (-R) and double hit lymphoma (DHL) as predictive of disease progression at 2y; however, none of these characteristics remained predictive on multivariate analysis. Additionally, IPI score ≥3 at the time of relapse preceding CART19, HGBL classification, no history of IL, MYC-R and DHL were also predictive of death at 2y on univariate analysis; however, none of these characteristics remained predictive on multivariate analysis. Conclusions Tumor characteristics, including recurring genetic mutations as detected by CLMA, may not independently predict for survival outcomes for DLBCL/HGBL pts following receipt of CART19. However, our finding that TNFRSF14 mutations predict for a lower rate of disease progression at 2y on univariate analysis may be explained by loss of the inhibitory effect of HVEM on T helper cells through binding of B and T lymphocyte attenuator (BTLA) (Cell. 2016 Oct 6;167(2):405-418.e13). Additionally, our finding that TP53 mutations did not predict for inferior PFS following receipt of CART19 is in agreement with that of a prior analysis (J Clin Oncol. 2022 Feb 1;40(4):369-381). Performance of CLMA on a larger number of tumor samples from DLBCL/HGBL pts subsequently treated with CART19, which is planned, may be informative.

Impact of Sex on Clinical Outcomes after CD19 CAR T-Cell Therapy for Large B-Cell Lymphoma: Response and Survival Are Significantly Superior in Female Compared to Male Patients

Sex differences in the incidence and mortality are evident in a wide range of cancers. This is not only due to sex-related variations in behavioral cancer risk factors, but also due to biological and molecular effects of sexual differentiation. Focusing on immunotherapeutic approaches like immune checkpoint inhibition or allogeneic stem cell transplantation, several reports have associated male sex with inferior outcomes. However, the exact impact remains controversial, and underlying mechanisms are incompletely understood. Here, we sought to explore the effects of the patient's biological sex on the outcomes of CD19 CAR-T cell therapy. To this end, we retrospectively analyzed disease and laboratory features together with survival in a cohort of 214 patients treated with axicabtagene ciloleucel (Axi-cel) for relapsed/refractory large B-cell lymphoma (LBCL) in the third- or later-line setting at four CAR-T centers. Predictors of progression-free survival (PFS) were analyzed by uni- and multivariate comparisons. The analyzed patient cohort comprised 119 male and 95 female patients, with a median age of 64 years (range 19-79). Most baseline patient characteristics were not significantly different for male and female patients (see attached table). Ferritin levels prior to lymphodepletion, however, were significantly higher in males (median 505 ng/ml vs. 325 ng/ml in females, p=0.025). The incidences of ASTCT grade ≥ 3 cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS) were not significantly different between females and males. However, objective response rates were significantly higher in female patients (88% vs. 75% in males, p=0.03). Additionally, females had a significantly superior PFS compared to males (median PFS not reached [95% CI 12.2 - NA months] in females vs. 4.2 months [95% CI 3.2 - 9.2 months] in males, Hazard ratio 1.8 [1.2 - 2.6], p=0.005, 1-year PFS estimate 61% in females vs. 39% in males). Overall survival (OS) was also significantly longer in females (median OS not reached in females vs. 22.6 months [95% CI 13.3 months - not reached] in males, Hazard ratio 1.7 [1.1 - 2.9], p=0.028). We confirmed the relevance of the patient's sex in multivariate analysis. We used Lasso modelling of variables with significant (p<0.05) association with PFS from univariate Cox regression analyses (ECOG, LDH, CRP and ferritin levels, Ann Arbor stage, bulky or extranodal disease [END], No. of therapy lines prior to CAR-T cell therapy and response to bridging therapy). Male sex, non-response to bridging, stage III/IV disease, END and No. of therapy lines remained independent risk factors for inferior PFS (Lasso coefficients >0.1), with male sex and non-response to bridging having the most significant effect (Lasso coefficient 0.54 for both variables). Finally, employing logistic regression of the independent variables from multivariate analysis, propensity score matching was used to better delineate the effect of sex on PFS. Sufficient balance was achieved between male and female patients, with all standardized mean differences below 0.12 after matching. In the matched analysis, PFS remained significantly superior for female patients (1-year PFS estimate 61% in females vs. 40% in males, log-rank p=0.008). For OS, the observed difference was of borderline significance in the matched dataset (1-year OS estimate 77% in females vs. 61% in males, log-rank p=0.051). Taken together, we demonstrate that female patients have significantly superior outcomes following Axi-cel therapy for r/r LBCL, even after careful adjustment for variables known to impact treatment results. A deeper understanding of the underlying mechanisms of these outcome disparities might enable the optimization of T cell-based treatment platforms in the future, both in female and male patients. Male patients may potentially benefit from intensified CAR-T (combination) treatment strategies.

Clinical Features, Treatment Patterns and Outcomes of 864 Newly Diagnosed Hodgkin Lymphoma Patients in Latin America and the Impact of PET Scan Availability on Survival: A Study from the Grupo De Estudio Latinoamericano De Linfoproliferativos (GELL)

Background: Hodgkin lymphoma (HL) is a lymphoid neoplasm with high cure rates. Around 90% of patients (pts) will achieve response to first-line treatment. Real-world studies in Latin America (LATAM) are lacking. Moreover, inequity in the access to imaging technology and drugs represent a real challenge for Latin American countries with palpable influences in patient outcomes. Herein, we describe the clinical features, treatment patterns, and outcomes of HL pts managed in LATAM. Method: We conducted a retrospective cohort study of adults aged ≥17 years with newly diagnosed HL across academic centers in 7 LATAM countries from 2003 to 2022, with follow-up through July 2023. Medical records were manually reviewed, and data were abstracted in a standardized form. Cancer staging was performed by Ann Arbor and German HL Study Group criteria. Survival probabilities were estimated with the Kaplan-Meier method and compared with the Log-rank test. Multivariable Cox regression models were fitted by cancer stage stratification. A landmark analysis was performed to assess the lack of PET scan availability at the end of treatment (EOT) in LATAM. Results: Of 965 pts identified, 864 had sufficient data for analysis. Pts were young (56% <40 years; median 36 [17-88]) with slight male predominance (53%). 9 (3%) pts were HIV positive. Nodular sclerosing (62%) and mixed cellularity (22%) were the most common HL subtypes (p<0.01). Clinically, most pts had good performance status (ECOG≤1, 96%), no B symptoms (62%) and normal serum LDH (60%). Mediastinal presentation was seen in 14%, bulky mass (>10 cm) 23%, nodal involvement >3 sites 34% and extranodal involvement 25%. Advanced stage was common (57%); 22% and 21% had favorable and unfavorable limited stage HL, respectively. ABVD was the most common first-line regimen (96%); 8 pts received BEACOPP, and 1 BV-AVD. Radiation was utilized in 40% of limited and 21% of advanced stage HL. Only 63% and 48% had interim (iPET) and EOT PET scan, respectively. Most pts were managed at private than public institutions (59%, p<0.01). With a median follow up of 65 [59-71] months the 5-yr overall survival (OS) and progression-free survival (PFS) rates in all HL pts were 85% (82-88, 95% CI not reached, NR) and 64% (60-69, 95% CI NR), respectively. Better OS and PFS were seen in pts younger than 60 (p<0.01), ECOG≤1 (p<0.01) and limited stage HL (p<0.01). Overall response rate at the EOT assessed by either PET or CT scan was 89% (76% complete and 13% partial). In those assessed by iPET, results yielded 86% keeping same plan, 7% de-escalation and 3% escalation. In our cohort, 11% had refractory HL and 18% relapsed after achieving response. Given the inferior PFS to first-line seen in our LATAM HL pts compared to historical cohorts, we looked at possible factors associated to early relapse. Those assessed by PET at the EOT had significantly superior 5-yr PFS than those assessed by CT scan (PET vs CT: favorable HL 91 vs 71%; unfavorable 83 vs 35%; advanced 79 vs 51%) ( Figure). OS was inferior only in pts with unfavorable HL not assessed by PET (94 vs 76%, p=0.03). In the multivariable analysis, the lack of PET assessment at the EOT was associated with short PFS in unfavorable (aHR 7.81 [1.46-41.88], p=0.02) and advanced (aHR 17.35 [4.66-64.61], p<0.01), and a non-statistically significant worse PFSvin favorable HL (aHR 5.05 [0.56-45.72], p=0.15). Other factors associated to short PFS were extranodal disease (aHR 35.29 [5.62-209.07], p<0.01) in unfavorable, and high serum LDH (aHR 2.31 [1.2-4.46], p=0.01) in advanced HL. Interestingly, pts with advanced HL managed in public institution had less risk for relapse than those in private institutions (aHR 0.13 [0.03-0.51], p<0.01). Conclusion: To our knowledge, this is the largest cohort of newly diagnosed HL pts in LATAM in the real-world setting. We observed similar clinical features in LATAM HL pts than those previously reported. ABVD was widely utilized in LATAM, and the 5-yr OS of 85% in all pts aligns with international estimates. However, our findings underscore the impact of limited access to PET scan at the EOT in LATAM, leading to lower PFS outcomes compared to those reported in developed countries. Despite this challenge, salvage therapy seems to rescue our LATAM HL pts, thus, OS remains optimal. To improve outcomes and minimize late effects following treatment completion, increasing the use of PET-adapted therapy for managing adult pts with HL in LATAM should be prioritized.

Impact of Diagnosis to Treatment Interval on Outcomes in Patients with Newly Diagnosed Marginal Zone Lymphoma - a US Multisite Study

Introduction Diagnosis to treatment interval (DTI) is an important prognostic factor in patients with newly diagnosed diffuse large B-cell lymphoma (Maurer M et al, JCO 2018) and mantle cell lymphoma (Epperla N et al, Blood Adv 2023) where patients with shorter DTI consistently show inferior survival. In marginal zone lymphoma (MZL), the use of first-line bendamustine and rituximab (BR) therapy may enhance progression-free survival (PFS) compared to cyclophosphamide-based regimens such as RCHOP/RCVP. However, the differences in outcomes may be influenced by other factors, such as the DTI, especially in observational studies. Until now, the prognostic significance of DTI in MZL has not been explored. Therefore, our objective was to assess the impact of DTI on outcomes for patients with newly diagnosed MZL. Methods This is a substudy of a previously reported multicenter, retrospective cohort that included adult MZL patients treated at 10 US medical centers on or after 1/1/2010. In this substudy, we included patients who initiated first-line BR, RCHOP, or RCVP within 120 days of diagnosis. Patients who were on observation or received antibiotics, local therapy (surgery or radiation therapy), or rituximab monotherapy were excluded. DTI was defined as the number of days from the MZL diagnosis to the start of immunochemotherapy (IC). Using concordance statistics for different DTI cutoffs, we determined 60 days as optimal for analysis. Patients who received treatment within 60 days from their diagnosis were classified into the short DTI group. To compare clinical characteristics between the two groups, univariable and multivariable (MV) logistic regression analyses were performed, accounting for missing data through multiple imputations. The primary endpoint of this analysis was PFS, while secondary endpoints included overall survival (OS) and the cumulative incidence of histologic transformation (HT). Predictors of PFS and OS were identified using Cox regression analysis. Results Of the 900 patients with newly diagnosed MZL included in the main study, 177 patients met the inclusion criteria and were included in this analysis, including 144 (81%) in the short DTI group and 33 (19%) in the long DTI group. The median time to treatment initiation was 27 days (range: 1-60) for the short DTI group and 81 days (range: 61-112) for the long DTI group. The median age was 61 years with 43% EMZL (n=77), 38% NMZL (67), and 19% SMZL (33) patients. Among the patients, 75% received BR as first-line treatment followed by R-CHOP (15%), and R-CVP (10%). A higher proportion of patients in the short DTI group had B symptoms compared to long DTI group (27% vs 3%, p=0.03, respectively). No significant differences were observed between the two groups in regard to MZL subtype, ECOG performance status, stage, LDH, or the choice of first-line IC. In the MV model, presence of B symptoms remained significantly associated with short DTI (OR=12.63, p=0.02). Short DTI was not associated with a statistically different PFS in a univariable assessment (HR=0.86, 95%CI=0.47-1.56), or in the MV model, adjusting for other prognostic factors (aHR=0.87, 95%CI=0.47-1.61, p=0.65, Figure 1A), while high LDH (aHR=2.07, 95%CI=1.06-4.07, p=0.034) and low albumin (aHR=2.31, 95%CI=1.10-4.85, p=0.027) at diagnosis were associated with significantly inferior PFS in the MV model. Additionally, the MV model indicated that patients who received BR had significantly better PFS compared to those who received R-CHOP/RCVP (aHR=0.50, 95% CI=0.29-0.86, p=0.01, Figure 1B). Short DTI was not associated with inferior OS in either univariable or MV models (MV: aHR=0.74, 95%CI=0.26-2.08, p=0.57). There were 12 transformation events in the study: 8 in the short DTI group and 4 in the long DTI group. The cumulative incidence of HT was not significantly different between the two groups (10-year CIF 13% versus 12%, respectively, p=0.22). Conclusion In MZL, a short DTI does not correlate with an inferior prognosis, despite being associated with certain unfavorable characteristics such as the presence of B symptoms. This lack of prognostic utility of DTI in newly diagnosed MZL, in contrast to aggressive B-cell lymphomas, may be intrinsically linked to the underlying biology of the disease. Furthermore, the observed improvement in PFS with BR compared to RCHOP/RCVP, as demonstrated in clinical trials like STiL and BRIGHT, cannot be attributed to differences in DTI.

Improving the Utilization and Tolerability of Thiotepa-Based Autologous Stem Cell Transplantation in Primary CNS Lymphoma

Background: Thiotepa-based autologous stem cell transplantation (ASCT) improves survival in primary central nervous system lymphoma (PCNSL) but up to 30-60% of patients are unable to receive ASCT after MATRix induction, frequently due to treatment-related adverse events. Common conditioning regimens such as thiotepa/BCNU or thiotepa/busulfan/cyclophosphamide have also been associated with risks of pulmonary toxicity or increased transplant-related mortality. Novel strategies to improve the utilization and tolerability of ASCT are therefore needed to maximize the curative potential of this therapy in PCNSL. Methods: This retrospective population-based study included all patients diagnosed with large B-cell lymphoma-type PCNSL who were intended for ASCT in the province of Alberta, Canada between 2011 and 2022. Provincial treatment guidelines recommended an abbreviated, low-intensity induction protocol to reduce toxicity and increase transplantation rates (Figure 1B). Step 1 included 2 cycles of rituximab/high-dose methotrexate (HD-MTX). Step 2 involved 1 cycle of rituximab/high-dose cytarabine (HDAC) for peripheral blood stem cell mobilization. Step 3 consisted of 2 cycles of rituximab/HD-MTX/HDAC and was made optional in July 2018 so that patients with sufficient disease response and performance status following Step 2 could proceed immediately to ASCT. Conditioning consisted of thiotepa 300 mg/m 2 ×2 days and busulfan 3.2mg/kg ×3 days (TT/Bu). Dose reductions of TT/Bu by 10% for every 5 years over the age of 60 were recommended as of May 2021. Progression-free survival (PFS) and overall survival (OS) were determined using the Kaplan-Meier method and compared between groups using the log-rank test. Results: The intention-to-transplant (ITT) cohort included 71 patients with median age 58 years (range 26-72), representing 81% of patients aged 18-60 and 55% of those aged 61-72 who were diagnosed with PCNSL in Alberta during the study period. The proportion of patients aged 61-72 who were treated with ITT increased from 42% before 2018 to 70% afterwards. Fifty-six (79%) ITT patients proceeded to ASCT while 15 (21%) did not due to poor performance status (n=6), treatment-related adverse events (n=5), or disease progression (n=4). There was 1 (1%) death due to infection-related non-relapse mortality (NRM) during induction. The routine omission of Step 3 starting in 2018 resulted in high transplantation rates at 29/35 (83%) compared to 27/36 (75%) in the preceding era. With median follow-up time 3.9 years, the 4-year PFS was 69% (95% CI 56-79%) and OS was 80% (95% CI 67-88%) in the ITT cohort (Figure 1A). For the 56 patients who received ASCT, 4-year PFS was 75% (95% CI 57-86%) and OS was 85% (95% CI 68-93%) from the time of ASCT. There was no significant difference in PFS between patients in complete response (CR)/unconfirmed CR versus partial response (PR) before ASCT (p=0.86); however, 5 patients with progressive disease before ASCT had inferior PFS compared to those with CR/CRu/PR (4-year PFS 40% vs 82%, p=0.0002). Relapse occurred in 8 (14%) patients at median 373 days (range 54-1411) after ASCT, including 7 with CNS relapse and 1 with systemic relapse. No patient in remission after ASCT received whole brain radiation therapy and most recovered without clinically significant neurologic deficits. There were no deaths due to transplant-related mortality. NRM occurred in 2 (4%) patients due to an unrelated cancer and stroke 1.1 and 4.3 years after ASCT, respectively. Among 27 patients >60 years old treated with ITT, 17 (63%) proceeded to ASCT, including 6 who received dose reductions of TT/Bu. The transplantation rate in this age group increased from 45% to 75% following the routine omission of Step 3. All 17 transplanted patients remain alive and in remission with median follow-up 2.5 years. Conclusion:In this real-world study of 71 patients with PCNSL, an abbreviated, low-intensity induction protocol resulted in high transplantation rates (~80%) and favorable long-term outcomes with 4-year OS 80%. Notably, TT/Bu conditioning achieved a low incidence of relapse with no transplant-related mortality observed, including among patients >60 years old. These data demonstrate that de-escalated induction therapy can result in improved rates of successful ASCT, thereby optimizing the outcomes of PCNSL.

Autologous Stem Cell Transplant in Fit Patients with Late Relapsed Diffuse Large B-Cell Lymphoma That Responded to Salvage Chemotherapy

Background: The new standard of care for fit patients with refractory or early relapse of diffuse large B-cell lymphoma (DLBCL) is chimeric antigen receptor T-cell (CAR-T) therapy. However, for patients with a relapse ≥12 months after completing frontline therapy, salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell transplant (ASCT) remains the standard of care. There is a need to characterize such patients and their survival in view of the recent shift in treatment paradigm. Methods: Patients with DLBCL that relapsed ≥12 months after R-CHOP or R-CHOP-like frontline therapy who underwent salvage therapy and ASCT at Mayo Clinic or University of Iowa between 07/2000 and 4/2020 were identified from institutional lymphoma and transplant databases. Clinical characteristics, treatment information, and outcome data were abstracted. Progression-free survival (PFS) and overall survival (OS) from the time of ASCT were analyzed using Kaplan-Meier method and Cox proportional hazards models. Statistical analyses were performed in JMP v15. Results: A total of 158 patients with late relapsed DLBCL who underwent salvage chemotherapy and ASCT were identified. Baseline characteristics at relapse/ASCT are shown in Table 1. Median time from frontline therapy completion to 1st relapse was 26.4 months (range 12.0-152.4). Median age at relapse was 63 years (range 19-77), and 96 (61%) patients were male. A minority (3; 3%) had ECOG PS ≥2. 43 (52%) patients had an elevated serum LDH level, 70 (65%) had advanced stage disease, and 12 (11%) had >1 extranodal involvement. Median line of salvage therapy was 1 (range 1-3), and 17 (11%) patients required >1 line of salvage therapy. Best response before ASCT was complete response (CR) in 97 (61%) and partial response (PR) in 61 (39%). Median age at ASCT was 64 years (range 19-78). Median follow-up after ASCT was 91.5 months (95% CI 74.0-103.3). Median PFS and OS were 54.5 (95% CI 31.9-77.8) and 99.8 (95% CI 60.3-144.5) months, respectively. The 2-year PFS and OS rates were 64% (95% CI 56-71) and 81% (95% CI 74-87), respectively. No statistically significant difference in PFS was seen based on age at ASCT, sex, serum LDH, stage, or extranodal site involvement of >1 at relapse (Table 2). However, patients who required > 1 line of salvage therapy, compared to those requiring 1 line of salvage therapy, had significantly inferior PFS (median 6.1 vs 61.8 months, P <0.0001) and OS (17.8 vs 111.7 months, P <0.0004). There was no statistically significant difference in survival in patients who achieved CR vs PR prior to ASCT, with a median PFS of 61.8 vs 37.8 months( P=0.21) and a median OS of 111.7 vs 78.3 months ( P=0.62). Patients who achieved CR after 1 line of salvage therapy had the most favorable PFS and OS, with a median PFS of 65.6 vs 45.4 vs 6.1 vs 7.6 months ( P=0.0004) and a median OS of 133.0 vs 88.9 vs 24.2 vs 17.6 months ( P=0.004) in patients achieving CR after 1 line of salvage therapy vs PR after 1 line of salvage therapy vs CR after >1 line of salvage therapy vs PR after >1 line of salvage therapy, respectively (Table 2). In multivariate Cox regression models adjusted for age at ASCT and sex, patients requiring > 1 line of salvage therapy, compared to those who required 1 line of salvage therapy, had significantly inferior PFS with a hazard ratio (HR) of 3.25 (95% CI 1.82-5.78, P <0.0001) and OS with a HR of 3.50 (95% CI 1.86-6.60, P=0.0001). However, there remained no significant difference in survival based on response status (CR vs PR) with a HR for PFS 0.78 (95% CI 0.52-1.17, P=0.23) and OS 0.93 (95% CI 0.58-1.47, P=0.74). Conclusions: Survival after ASCT was excellent in patients with late relapsed DLBCL achieving CR after 1 line of salvage chemotherapy. Favorable survival outcomes were seen in patients who achieved PR after 1 line of salvage therapy. These data support the current clinical practice of ASCT consolidation in these patients. However, post-ASCT survival was poor in patients who required more than 1 line of salvage chemotherapy, despite achieving a satisfactory response to subsequent lines of salvage therapy. Alternative treatment strategies such as CAR-T therapy should be considered in such patients.

Rituximab, Bendamustine and Cytarabine Followed By Venetoclax (V-RBAC) in High-Risk Older Patients with Mantle Cell Lymphoma: A Phase 2 Study By the Fondazione Italiana Linfomi (FIL)

Introduction: The R-BAC regimen is considered among standard first-line treatments for elderly fit patients with mantle cell lymphoma (MCL). We previously reported (RBAC500 trial) a significantly inferior progression-free survival (PFS) for patients with high risk (HR) features, namely blastoid morphology and/or elevated Ki67 proliferative index, as compared to other patients, that were defined as low risk (LR). Indeed, when treated with R-BAC, LR patients had excellent outcome, albeit no maintenance therapy was delivered. Methods: We designed a phase 2 prospective multicenter study, which enrolled patients aged ≥65 years and fit according to the geriatric CGA assessment, or age ≤64 years if not eligible to high-dose chemotherapy plus transplantation. Asymptomatic patients with non-nodal disease were excluded. At presentation patients were allocated by central review as LR or HR, depending on tumor morphology (blastoid versus others), Ki67 expression (≥30% versus others), or presence of TP53 mutation and/or deletion. Patients with any of the three risk factors were classified as HR. Patients with LR disease were treated with 6 cycles of R-BAC (rituximab 375 mg/m2 d 1; bendamustine 70 mg/m2 d 1,2; cytarabine 500 mg/m2 d 1,2,3), while HR patients received abbreviated induction with 4 R-BAC followed by consolidation (4 months, 800 mg/d), and maintenance (20 months, 400 mg/d) with venetoclax. The primary endpoint was 2-years PFS for the HR patients. The sample size was calculated with the one arm non parametric survival analysis (alpha-error 0.05, power 90%), assuming that the addition of venetoclax would improve 2-years PFS from 40% (null hypothesis) to 60%. Tumor response was assessed with Lugano criteria. All patients were analyzed by real-time quantitative PCR at baseline on peripheral blood and bone marrow samples for minimal residual disease (MRD) evaluation, and HR patients were followed up at different time points. Results of this specific analysis will be subject of future reports. This trial was registered at ClinicalTrials.gov Identifier: NCT03567876. Results: Overall, 140 patients from 35 centers of the Fondazione Italiana Linfomi (FIL) were prospectively enrolled between 2018 and 2021. Of them, 54 were HR (39%). Median age was 72 (range 57-79), and 44% had elevated MIPI. LR and HR patients had similar clinical characteristics, but differed for LDH, and MIPI, both being significantly higher in the HR group. Overall, 28 (20%) patients had TP53 mutations, 19 (14%) had TP53 deletions, Ki67 was ≥30% in 34 (24%), and blastoid variant was diagnosed in 13 patients (9%, Figure 1A). Toxicity during R-BAC was in line with previous reports, while most frequent grade >=3 adverse events during venetoclax treatment consisted of neutropenia (21%), followed by skin reactions (10%). Of note, there were 5 deaths due to COVID-19 infection in patients in CR (4 LR, 1 HR). Overall response at the end of R-BAC differed between HR and LR patients (85% vs 99%, p=0.001), as was for complete response (61% vs 91%, p=0.0001). Of the 54 HR patients, 43 (80%) started venetoclax consolidation, 37 (69%) started the maintenance phase, with 26 patients (48%) completing the whole treatment per protocol. Of 10 patients that started Venetoclax in partial remission (PR) or stable disease after R-BAC, 3 converted to CR, 1 maintained PR, while 6 patients progressed during maintenance. After a median follow-up of 34 months, the 2-years PFS for the whole population was 74.9% (95% CI 66-82), and OS was 80% (95% CI 72-85). Patients with HR MCL had 2-years PFS and OS of 58% (95% CI 43-70) and 66% (95% CI 50-77), respectively, which were significantly lower than LR patients (85% and 88%, respectively, p=0.0001 for both, see Figure 1B). Predictors of PFS using Cox regression models adjusted for MIPI were blastoid morphology (Hazard Ratio 3.51), and TP53 mutation (Hazard Ratio 4.17), with Ki67, and TP53 deletions that lost their power in multivariate analysis. Conclusions: The VR-BAC trial represents the first prospective study that stratified upfront patients with MCL to different treatments according to the risk profile. In this trial the null hypothesis (2-years PFS 40%) was rejected in HR patients, suggesting that the addition of venetoclax to R-BAC improves the performance of the induction strategy. These results point to the importance of identifying HR patients since initial diagnosis.

The effective radiation dose to immune cells predicts lymphopenia and inferior cancer control in locally advanced NSCLC

PurposeTo explore the association of the effective dose to immune cells (EDIC) with disease control, lymphopenia, and toxicity in patients with non-small cell lung cancer (NSCLC) and identify methods to reduce EDIC. MethodsWe abstracted data from all patients with locally advanced NSCLC treated with chemoradiation with or without consolidative immunotherapy over a ten-year period. Associations between EDIC and progression-free survival (PFS) and overall survival (OS) were modeled with Cox proportional hazards and Kaplan-Meier method. Logistic regression was used to model predictors of lymphopenia and higher EDIC. Analyses were performed with EDIC as a continuous and categorical variable. Lymphopenia was graded per CTCAE v5.0. ResultsOverall, 786 patients were included (228 of which received consolidative immunotherapy); median EDIC was 4.7 Gy. Patients with EDIC < 4.7 Gy had a longer median PFS (15.3 vs. 9.0 months; p < 0.001) and OS (34.2 vs. 22.4 months; p < 0.001). On multivariable modeling, EDIC correlated with inferior PFS (HR 1.08, 95 % CI 1.01–1.14, p = 0.014) and OS (HR 1.10, 95 % CI 1.04–1.18, p = 0.002). EDIC was predictive of grade 4 lymphopenia (OR 1.16, 95 % CI 1.02–1.33, p = 0.026). EDIC ≥ 4.7 Gy was associated with increased grade 2 + pneumonitis (6-month incidence: 26 % vs 20 %, p = 0.04) and unplanned hospitalizations (90-day incidence: 40 % vs 30 %, p = 0.002). Compared to protons, photon therapy was associated with EDIC ≥ 4.7 Gy (OR 5.26, 95 % CI 3.71–7.69, p < 0.001) in multivariable modeling. ConclusionsEDIC is associated with inferior disease outcomes, treatment-related toxicity, and the development of severe lymphopenia. Proton therapy is associated with lower EDIC. Further investigations to limit radiation dose to the immune system appear warranted.

The impact of sMICA/sMICB on immunochemotherapy outcomes in newly diagnosed diffuse large B-cell lymphoma.

Soluble MHC class I-related chain A (sMICA) and B (sMICB) play a critical role tumor evolution and poor prognosis through an immune evasion mechanism. Thus, this study determines the interaction between sMICA/sMICB and the tumor immune environment in newly diagnosed diffuse large B-cell lymphoma (ND-DLBCL). We analyzed sMICA/sMICB, cytokine in serum, and macrophage polarization analysis in tissue samples before the first chemotherapy administration. This research was performed to investigate the correlation between sMICA/sMICB expression and treatment outcomes as well as their influence on the immune system within ND-DLBCL. Of the 262 patients, 47.3% (n = 124) presented stage III or IV at diagnosis and 50.8% (n = 133) had a high International Prognostic Index (IPI ≥ 3). The patients with high (p = 0.034 and 0.004), elevated lactate dehydrogenase (p = 0.002 and 0.030), advanced stage (p = 0.003 and 0.012), and higher IPI risk (p = 0.009, and 0.032) correlated with the detection of sMICA or sMICB. The median progression-free survival (PFS) of patients with sMICA (p = 0.006) or sMICB (p =0.032) was inferior. Among the patients with advanced-stage or high IPI, those with sMICA or sMICB presented an inferior PFS and OS compared to those without. TNF-a, a pro-inflammatory cytokine, showed statistical significance with detected sMICA (p = 0.035) or sMICB (p = 0.044). Among anti-inflammatory cytokines, IL-1RA (P-value = 0.013) and IL-10 (p = 0.005) were associated with detecting sMICB, but not sMICA. In tissue samples, sMICA or sMICB detection did not correlate with the CD68/CD163 ratio. Conclusively, the identification of sMICA/sMICB presented unfavorable immunochemotherapy outcomes, and it was assumed that sMICA or sMICB and various cytokines interact, but the relationship with macrophage differentiation is unclear. Therefore, further research is needed to determine the relationship between sMICA/sMICB and tumor microenvironment in DLBCL.

Sensitive MRD Detection from Lymphatic Fluid after Surgery in HPV-Associated Oropharyngeal Cancer.

Our goal was to demonstrate that lymphatic drainage fluid (lymph) has improved sensitivity in quantifying postoperative minimal residual disease (MRD) in locally advanced human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) compared with plasma, and leverage this novel biofluid for patient risk stratification. We prospectively collected lymph samples from neck drains of 106 patients with HPV (+) OPSCC, along with 67 matched plasma samples, 24 hours after surgery. PCR and next-generation sequencing were used to quantify cancer-associated cell-free HPV (cf-HPV) and tumor-informed variants in lymph and plasma. Next, lymph cf-HPV and variants were compared with TNM stage, extranodal extension (ENE), and composite definitions of high-risk pathology. We then created a machine learning model, informed by lymph MRD and clinicopathologic features, to compare with progression-free survival (PFS). Postoperative lymph was enriched with cf-HPV compared with plasma (P < 0.0001) and correlated with pN2 stage (P = 0.003), ENE (P < 0.0001), and trial-defined pathologic risk criteria (mean AUC = 0.78). In addition, the lymph mutation number and variant allele frequency were higher in pN2 ENE (+) necks than in pN1 ENE (+) (P = 0.03, P = 0.02) or pN0-N1 ENE (-) (P = 0.04, P = 0.03, respectively). The lymph MRD-informed risk model demonstrated inferior PFS in high-risk patients (AUC = 0.96, P < 0.0001). Variant and cf-HPV quantification, performed in 24-hour postoperative lymph samples, reflects single- and multifeature high-risk pathologic criteria. Incorporating lymphatic MRD and clinicopathologic feature analysis can stratify PFS early after surgery in patients with HPV (+) head and neck cancer. See related commentary by Shannon and Iyer, p. 1223.

Autologous Transplant (auto-HCT) Is Associated with Improved Clinical Outcomes Compared to CAR-T Therapy in Patients (pts) with Large B-Cell Lymphoma (LBCL) Achieving a Complete Remission

Introduction: CAR-T therapy is the standard of care for pts with relapsed LBCL as early as in the second line in those with early relapse or with primary refractory disease. In practice, pts who are intended to receive CAR-T, commonly require interim therapy before leukapheresis, wherein a small fraction may achieve a complete remission (CR). Having chemosensitive disease, these pts can be considered for auto-HCT. Also, there are reports indicating the efficacy of CAR-T therapy in CR pts (Strati et al., Haematologica, 2023; Wudhikarn et al., Blood Adv, 2022). We compared the outcome of pts with LBCL who received CAR-T vs. auto-HCT while in a CR. Methods: Pts aged 18-75 years with DLBCL or primary mediastinal lymphoma who received CAR-T (between 2018-2021) or auto-HCT (between 2015-2021) while in a CR by PET or CT were included in this analysis using the data from the Center for International Blood &amp; Marrow Transplant Research (CIBMTR) registry. Primary endpoints included progression-free survival (PFS) and overall survival (OS). Treatment-related mortality (TRM) and relapse rate were among the secondary endpoints. Results: We identified 360 pts with LBCL who were in a CR before receiving CAR-T (n=79, tisa-cel 53%, axi-cel 46%, and liso-cel 1%) or auto-HCT (n=281). Median follow-up was 24.7 months (range 3.3-49.4) for the CAR-T cohort and 49.7 months (range 3.0-95.4) for the auto-HCT cohort. Selected baseline characteristics are shown in Table 1. CRs were confirmed by PET scan in 90% of CAR-T pts and 99.6% of auto-CAR-T pts (p &amp;lt; 0.01). The most common lymphodepletion regimen for CAR-T was Cy/Flu (82.3%) and the most common conditioning regimen for auto-HCT was BEAM (77.6%). Thirty-seven (13.2%) of auto-HCT pts had a later CAR-T but no pts from the CAR-T cohort had subsequent auto-HCT. In univariate analysis, treatment with CAR-T was associated with a higher rate of relapse at 2 years (48% vs. 27.8%; p &amp;lt; 0.001), a lower rate of 2-year PFS (47.8% vs. 66.2%; p &amp;lt; 0.001) and lower 2-year OS (65.6% vs. 78.9%; p=0.037). There was no difference in rates of 2-year TRM (4.1% vs. 5.9%; p=0.673). Similarly, focusing on patients with early (12 months) treatment failure (CAR-T =57 and auto-HCT=163), treatment with CAR-T was associated with a higher 2-year relapse rate (45.9% vs. 22.8%; p &amp;lt;0.001) and an inferior 2-year PFS (48.3% vs.70.9%.; p &amp;lt;0.001) compared to auto-HCT (figure-2) while there was no difference in 2-year OS or TRM. In the multivariable analysis of outcomes, treatment with CAR-T was associated with higher risk of relapse (HR 2.18; p &amp;lt; 0.0001) and an inferior PFS (HR 1.83; p=0.0011) compared to auto-HCT. There was no difference in the risk of TRM (HR 0.59; p=0.36) or OS (HR 1.44; p=0.12). Conclusions: In pts with relapsed LBCL who achieve a CR, treatment with auto-HCT is associated with a lower relapse rate and an improved PFS compared to CAR-T, including in pts with early treatment failure (within 12 months). These results are in line with previously reported improved clinical outcomes with auto-HCT compared to CAR-T in pts in partial remission (Shadman et al. Blood, 2022). The data support utilization of auto-HCT in pts with relapsed LBCL achieving a CR.

Metabolic Tumor Volume from Baseline PET/CT Improves Stratification in the High IPI Risk Patients with Diffuse Large B‐Cell Lymphoma

Background: In the rituximab era, the international prognostic index (IPI) risk stratification was not enough to predict outcome in patients with diffuse large B cell lymphoma (DLBCL). Previous studies showed the Metabolic tumor volume（MTV） from baseline [ 18F]FDG PET/CT could be used to predict outcome. In this study, we evaluated the prognostic value of IPI and MTV in DLBCL patients. Patients and methods: A total of 262 de novo DLBCL patients who were treated with the R-like chemotherapy were retrospectively analyzed in this study. The IPI and MTV were compared to the Overall Survival (OS) and Progression Free Survival (PFS). Results: The MTV is better than TLG and SUVmax for predicting disease progression. The cutoff value of MTV was 444 cm 3. Patients with high MTV showed inferior OS and PFS ( p &amp;lt; 0.001, respectively). Although the IPI remains predictive it distinguishes only 2 risk groups, rather than the 4 groups originally described. Further analysis showed high MTV could identify a subgroup of patients with extremely inferior OS and PFS in high IPI risk patients ( p = 0.0089 and p= 0.024, respectively). Multivariate analysis revealed that high MTV is a significant poor prognostic factor for both OS (HR 3.168[1.81-5.56], p &amp;lt;0.001) and PFS (HR 2.637 [1.51-3.71], p &amp;lt;0.001). Conclusions: Our study suggests that MTV from baseline PET/CT is an important prognostic factor in DLBCL patients, allowing the identification of an inferior outcome subgroup in high-risk patients, which may help to guide treatment in clinical trial.

Quantity and Functional Exhaustion of Mucosal-Associated Invariant T Cells in Acute Myeloid Leukemia: Friends or Foes?

Abstract Introduction Acute Myeloid Leukemia (AML) is a hematological malignancy affecting hematopoietic progenitor cell differentiation, proliferation, and cell cycle progression, possibly involving disturbances in host immune function. Comprehensive understanding of the immune system composition and function in AML patients is crucial for developing novel immunotherapeutic strategies. Mucosa-Associated Invariant T cells (MAITs), as a subset of unconventional T cells, bridge innate and adaptive immunity and have been predominantly studied in the context of mucosa-related cancers. However, their role in AML remains largely unexplored. Investigating the association between MAITs and AML is of significant importance for understanding the immune escape mechanisms in AML, developing novel immunotherapeutic approaches, and predicting patient prognosis. Methods This study aimed to delineate the longitudinal immune profile of MAITs during AML pathogenesis and treatment, which may contribute to understanding immunological changes of MAITs in AML and predicting patient prognosis. In this prospective study, we collected peripheral blood or bone marrow samples from 131 AML patients, including 99 newly diagnosed cases, 18 in remission, and 14 in relapse, as well as 69 healthy controls. We performed multi-parameter flow cytometry for phenotypic and functional analysis of MAITs and explored their relationship with disease features, progression, and prognosis. Results We initially demonstrated that MAITs reflected immunological defects in AML patients. MAITs showed signs of depletion in both frequency and absolute count at initial diagnosis (p&amp;lt;0.0001) (Fig. 1A), especially in the CD8 + MAITs subset. The frequency of MAITs reflected AML cell genetics, tumor burden, disease status, and treatment responsiveness (Fig. 1B). AML patients exhibited reduced frequency of effector memory MAITs (p&amp;lt;0.0001) and increased frequency of terminal differentiated MAITs (p&amp;lt;0.0001) in peripheral blood (Fig. 1C), indicating altered reactivity of MAIT cells to antigen stimulation. MAITs displayed a state of high activation and even exhaustion, as evidenced by upregulated PD-1 expression. Impaired secretion of Th1-type cytokines and increased secretion of Th17-type cytokines (Fig. 1D), granzyme B, and perforin were observed in MAITs, while MAITs also shifted towards secreting tumor-promoting cytokines such as IL-8. Lower frequency of MAITs was correlated with inferior Overall Survival (OS) and Progression-Free Survival (PFS) (Fig. 1E). Multivariate analysis identified MAITs frequency &amp;lt;2.12% as an independent prognostic factor affecting OS. Conclusion Our study highlights the role of MAITs in immunological defects in Acute Myeloid Leukemia and reveals their functional impairment and enhanced tumor-promoting effects. The frequency of MAITs in peripheral blood reflects the genetic features, tumor burden, disease status, and treatment responsiveness of AML patients. Lower frequency of MAITs is associated with inferior OS and PFS, serving as a prognostic indicator for AML.

Efficacy of Brentuximab Vedotin Maintenance Therapy Following Autologous Stem Cell Transplantation in Patients with Relapsed/Refractory Classical Hodgkin Lymphoma with and without Pre-Transplant Exposure to Novel Agents

Background: Maintenance therapy with brentuximab vedotin (BV) after autologous stem cell transplantation (ASCT) improved progression-free survival (PFS) among high-risk patients (pts) with relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL) in the phase III AETHERA trial. However, cHL treatment has changed significantly since that trial with frequent incorporation of BV and PD-1 inhibitors into earlier lines of therapy. The efficacy of BV maintenance may be different among pts who receive novel agents before ASCT. Methods: Pts with a diagnosis of R/R cHL who underwent ASCT between 2010 and 2022 were identified at 5 US transplant centers. Pts receiving no systemic post-ASCT maintenance or BV maintenance were included, while pts receiving investigational maintenance treatments were excluded. Medical records were reviewed to identify clinical variables. Results: 921 pts were identified. Median age was 32 yrs (IQR 24-44). 641 pts (70%) had primary refractory disease or relapsed within 12 months of frontline therapy, 326 (35%) had extranodal disease at relapse, and 173 (19%) had B symptoms at relapse. Pts received a median of 2 (1-9) lines of therapy before ASCT, including 295 (32%) who received ≥3 lines. 425 (46%) pts received BV before ASCT (including 24 pts as part of frontline treatment). 70 pts (8%) were BV-refractory (defined as failure to achieve an objective response to any BV-based treatment). 169 (18%) received a PD-1 agent with salvage treatment. 638 pts (69%) had a complete response on pre-ASCT positron emission tomography (PET). BEAM (71%) or CBV (21%) conditioning were used for most pts and 236 pts (26%) received peri-ASCT radiation. 224 pts (24%) received post-ASCT BV maintenance (including 37% of pts undergoing ASCT from 2015-2022). Compared to pts receiving no maintenance, pts receiving BV maintenance were more likely to have primary refractory/early relapsed disease (79% vs 67%, p&amp;lt;0.001), have received only 1 salvage regimen (79% vs 65%, p=0.001), and received BEAM conditioning (83% vs 67%, p&amp;lt;0.001). BV maintenance pts were less likely to receive peri-ASCT radiation (20% vs 28%, p=0.022). The median number of BV maintenance cycles was 10 (1-18) and the most common reason for discontinuation was neuropathy. Median post-ASCT follow-up was 4.9 yrs. 5-yr PFS and OS after ASCT were 70% (95% CI 67-74%) and 85% (83-88%), respectively. Because BV-refractory pts were much less likely to receive BV maintenance (p=0.0044) and had inferior PFS (HR 2.2, p&amp;lt;0.001) (and therefore would serve as a confounder), we excluded BV-refractory pts from additional analyses. Use of BV maintenance was associated with improved PFS (5-yr 81% vs 67%, HR 0.47 [0.33-0.69], p&amp;lt;0.001) and OS (5-yr 92% vs 83%, HR 0.38 [0.20-0.73], p=0.004). The benefit of BV maintenance depended upon pre-ASCT therapy. BV maintenance was associated with a significant improvement in PFS for pts who received no novel agents before ASCT (HR 0.41 [0.25-0.65], p&amp;lt;0.001), but not for BV-treated (HR 0.69 [0.38-1.25], p=0.22) or PD-1-treated pts (HR 0.63 [0.13-3.03], p=0.56) ( Figure). Among pts with 0-1 modified AETHERA risk factors, BV maintenance was not associated with a significant PFS benefit in any treatment subgroup (no novel agents, HR 0.50, p=0.087; BV-treated, HR 1.28, p=0.67; PD-1-treated, HR 2.97, p=0.44). For pts with 2+ modified AETHERA risk factors, BV maintenance significantly improved PFS in the no novel agent group (HR 0.35, p&amp;lt;0.001) but not in the BV-treated (HR 0.55, p=0.099) or PD-1 treated groups (HR 0.24, p=0.19). In multivariable analyses that included key variables (age, year of ASCT, conditioning regimen, peri-ASCT radiation, early relapse/primary refractory disease, B symptoms, extranodal sites, pre-ASCT PET, lines of therapy), BV maintenance was associated with a significant PFS benefit among pts who received no novel agents before ASCT (HR 0.27 [0.12-0.65], p&amp;lt;0.001), but not for pts treated with BV (HR 0.56 [0.28-1.10], p=0.091) or PD-1 blockade (HR 1.10 [0.22-5.56], p=0.91) before ASCT. Conclusions: In this large cohort, BV maintenance was associated with the clearest benefit among pts who received only chemotherapy before ASCT. We were unable to identify a significant improvement in PFS for pts receiving novel agents before ASCT (which could be due to insufficient power to detect a small benefit in this population), suggesting that if these pts benefit from BV maintenance, its impact is likely more limited.

Impact of 1q21 Gain and Amplification on Daratumumab-Treated Multiple Myeloma Patients: Real-World Data from the Australia-New Zealand and Asia-Pacific Myeloma and Related Diseases Registries

Introduction: Gain/amplification of 1q21 (1q21+) is found in 40% of patients (pts) with newly diagnosed Multiple Myeloma (MM). There is increasing evidence that presence of gain of 1q21 [gain(1q21), 3 copies] or amplification of 1q21 [amp(1q21), ≥4 copies] are independent poor prognostic factors. A recent post-hoc analysis of the ICARIA-MM and IKEMA studies showed that the addition of monoclonal anti-CD38 antibody isatuximab in combination with pomalidomide-dexamethasone or carfilzomib-dexamethasone abrogated the negative impact of 1q21 on progression-free survival (PFS). However, the impact of 1q21+ has not been consistently assessed in daratumumab (Dara) exposed pts. Methods: We identified MM pts treated with Dara between Jan 2020 and Jan 2023 from the Australia-New Zealand and Asia-Pacific Myeloma and Related Diseases Registries. Pts who had interphase fluorescence in situ hybridization (FISH) testing were included. High-risk cytogenetics (HRCyto) was defined as the presence of t(4;14), t(14;16) or del(17p) by FISH, and standard risk cytogenetics (SRCyto) as pts without 1q21+ and HRCyto. Pt groups analysed were: (1) without 1q21+ vs with 1q21+ (2) SRCyto vs isolated 1q21+ vs HRCyto without 1q21+ vs HRCyto with 1q21+. Subgroup analyses performed include: (3) gain(1q21) vs amp(1q21). Overall survival (OS) and PFS from commencement of Dara were estimated using the Kaplan-Meier method. Comparisons of PFS and OS were performed using the log-rank test. Categorical data were compared using a chi-square test and continuous variables with a rank-sum test. Results: Of 654 pts who received Dara, 451 had interphase FISH testing performed and were included. There were 132 pts with 1q21+ [gain(1q): 23, amp(1q):14, gain/amp status unknown: 95] and 319 without. Median follow up was 15 months (95% CI 14-18). Median prior lines of therapy was 1 (IQR 1-2). Dara-based regimens used were: Dara monotherapy (17.7%), Dara-bortezomib-dex (54.6%), Dara-lenalidomide-dex (11.3%), Dara-pomalidomide-dex (DPd) (9.3%), Dara-carfilzomib-dex (DKd) (2.5%) and Dara-bortezomib-lenalidomide-dex (4.6%). There were no differences in age, gender, ECOG, line of therapy in which Dara was used, or rate of autologous stem cell transplantation between pts with 1q+ vs pts without (Table 1). Pts with 1q21+ had higher rates of other HRCyto (37.1% vs 20.4%; p=0.005) and ISS Stage 3 disease (44.1% vs 29.3%; p=0.005) vs those without 1q21+. There was no significant difference in overall response rate (65.9% vs 71.6%; p=0.32). Through univariate analyses, PFS for 1q21+ pts was significantly shorter than those without 1q21+ [median PFS 8.2 vs 18.4 months (HR 1.7, 95% CI 1.3-2.3; p&amp;lt;0.001)] (Figure 1). This difference was still significant when adjusted for ISS, the presence of other HRCyto and country of treatment (HR 1.61, 95% CI 1.17-2.22; p=0.004). Pts with 1q21+ with or without HRCyto, and those with HRCyto and no 1q21+ had inferior PFS vs SRCtyo (median PFS 7.7 vs 8.9 vs 8.5 vs 30.3 months; p&amp;lt;0.001) (Figure 2). Of the pts where 1q21+ copy number was available, OS was significantly poorer in pts with amp(1q) vs those with gain(1q) (median OS 22.6 vs 46.9 months; p=0.035). There was also a trend towards poorer PFS in pts with amp(1q) (median PFS 4.9 vs 10.5 months; p=0.096) Conclusions: 1q21+ often co-exists with other HRCyto abnormalities. However, it remains an independent negative prognostic marker. The use of Dara does not appear to abrogate the negative impact of 1q21+ on PFS. Amp(1q21) potentially confers an even poorer outcome. This finding differs from an earlier retrospective study (Parrondo et al, Blood 2022), although &amp;lt;10% of patients in our study received DKd and DPd combinations. As such, more data on Dara in combination with carfilzomib and pomalidomide is needed.

Loncastuximab in High-Risk and Heavily-Pretreated Relapsed/Refractory Diffuse Large B-Cell Lymphoma: A Real World Analysis from 21 US Centers

Background: In the LOTIS-2 study, patients (pts) with relapsed/refractory (R/R) DLBCL treated with loncastuximab-tesirine (lonca), a CD19 directed antibody-drug conjugate, demonstrated an overall response rate (ORR) and complete response rate (CRR) of 48.3 % and 24.1%. However, there is a paucity of data evaluating outcomes with lonca in the real-world setting (RWS). Hence, we performed a multicenter retrospective study to describe pt characteristics and clinical outcomes in R/R DLBCL pts receiving lonca in this setting. Methods: This retrospective study included pts with R/R DLBCL treated with commercial lonca at 21 academic centers in USA. Clinicopathologic data, treatment outcomes and adverse event (AE) data were collected. Progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier method and characteristics associated with survival and CR calculated using Cox proportional hazards model and logistic regression. Response was assessed per institutional standards. Results: 187 pts were analyzed with a median follow-up of 12.5 months (mo). Median age was 68 years (range 22-95), 64% male, and 85% white ( Table 1). Most common histology was DLBCL (55% de novo, 22% transformed from low-grade) and 19% were double hit (DH). Thirty-two percent (n=59) had primary refractory disease, 17% (n=31) prior autologous transplant, and 60% (n=112) prior CAR T-cell therapy (CART). Median number of treatment lines before lonca was 4 (1-11) with 81% (n=151) receiving lonca in 4 th line (4L) or later and 8 pts treated off-label in 2 nd line. More pts receiving lonca in ≥4L had prior CART (72% vs 8%, p &amp;lt;0.001). CD19 status was confirmed prior to lonca in 128 pts (68%) with 109 (58%) confirmed CD19+. The ORR/CRR were 33% and 14%, respectively. Median PFS was 2.1 mo (95%CI=1.8-2.6) and median OS 4.6 mo (95%CI=3.7-5.8). 12-month PFS and OS were 12% and 20%. The CRR in 2L/3L, 4L, and &amp;gt;4L were 15%, 13%, and 15% with ORR of 44%, 26%, and 33%, respectively. Figure 1 shows PFS stratified by response with median PFS not reached in those achieving CR. Patients with a CR to last therapy prior to lonca had superior median PFS (8.8 vs 2.0 mo, p&amp;lt;0.01) and OS (10.8 vs 4.5 mo, p =0.01). Factors associated with achieving CR to lonca included CR to last prior therapy (OR 8.3, p&amp;lt;0.01) and nonGCB subtype (OR 3.9, p=0.02). No pts with bulky disease (&amp;gt;10 cm) had objective response. In multivariable analysis (MVA) including factors in Table 1, elevated LDH (HR 1.8, p=0.02; 95%CI=1.1-2.9) and bulky disease (HR 1.7, p=0.03; 95%CI=1.1-2.6) were associated with inferior PFS while CR to last therapy was associated with superior PFS (HR 0.2, p=0.02; 95%CI=0.05-0.76). Bulky disease (HR 2.3, p&amp;lt;0.01; 95%CI=1.4-3.5), HGBL histology (HR 6.1, p&amp;lt;0.01; 95%CI=2.6-14.5), and elevated LDH (HR 2.0, p&amp;lt;0.01; 95%CI=1.2-3.3) were associated with inferior OS, while CR to last therapy (HR 0.4, p=0.05; 95%CI=0.13-0.98) was associated with superior OS in MVA. Neither CD19 status nor prior CART were associated with PFS, OS, or CR. In pts receiving lonca after CART, ORR/CRR were 31% and 15%, respectively, and median PFS/OS were 2.0mo (95%CI=1.6-2.7) and 4.6mo (95%CI=3.2-6.1). In pts who received tafasitamab (n=15) and CART (n=7) after lonca, CR was 13% and 29%, respectively. The most commonly documented AE was cytopenias (45%), followed by peripheral edema, and rash (27% and 27% respectively). Infection was seen in 5% and AEs led to lonca discontinuation in 14%, including peripheral edema (24%) and rash (28%). Conclusions: In this heavily pre-treated population enriched with prior CART exposure, HGBL, and DHL, ORR and CRR to lonca were lower than previously reported. Nonetheless, we found that pts who achieve a CR to lonca have favorable outcomes and factors associated with achieving a CR include lack of bulky disease, nonGCB subtype, and achieving a CR to most recent therapy prior to lonca. Receipt of prior CART did not negatively impact outcomes to lonca. Furthermore, responses were seen with CD19-directed therapies following lonca failure, suggesting sequencing of CD19 therapy pre and post lonca was successful.

Detectable Somatic Variants Using Next Generation Sequencing (NGS) Post Allogeneic Hematopoietic Cell Transplant (Allo-HCT) Predict for High Relapse Risk in Acute Myeloid Leukemia (AML) and Myelodysplastic Syndromes (MDS)

Introduction: NGS is increasingly being utilized to identify pathogenic somatic and targetable variants in patients with newly diagnosed AML and MDS. Patients with high-risk disease are typically recommended to undergo allo-HCT as consolidation, upon achieving morphological complete remission (CR). But, despite achieving hematologic CR, patients often have detectable somatic variants pre allo-HCT that predict for increased risk of disease relapse. Longitudinal monitoring of somatic variants via NGS at diagnosis, pre-allo-HCT and post allo-HCT can assist in prognostication and identify patients that remain at high risk of relapse despite allo-HCT. Methods: Patients with AML or MDS who underwent a first allo-HCT and completed NGS testing at day +100 between years 2016 to 2021 were identified from the transplant registry of Mayo Clinic in Florida. The primary aim of the study was to evaluate the prognostic impact of detectable variants via NGS at day +100 days post allo-HCT on the following outcomes: 1) overall survival (OS), 2) relapse, 3) progression-free survival (PFS), and 4) non-relapse mortality (NRM). Disease risk was assessed based on European Leukemia Network (ELN) 2022 risk classification for AML and Revised International Prognostic Scoring System (R-IPPS) for MDS. Baseline variables were compared between patients with and without mutation at day +100 days post allo-HCT using Wilcoxon rank sum test for continuous variables and Fisher's exact test for categorical variables. Kaplan-Meier (KM) method was used to estimate freedom from events at different time points and draw corresponding survival curves. Results: 105 patients who underwent allo-HCT for AML and MDS and completed NGS testing at day +100 were included in the study population. Median age of the study population was 63 years (22-74) and 58% were of the male gender. Median HCT comorbidity score (HCT-CI) and KPS Karnofsky performance score (KPS) were 3 (0-8) and 90 (60-100), respectively. Matched unrelated donor (50%) and peripheral blood stem cells (98%) were the most common donor and graft source, respectively. Median number of lines of therapy pre allo-HCT was 1(0-6) and 52 (50%) patients had detectable variants after completion of chemotherapy and prior to allo-HCT. Seventeen (16%) had detectable variants via NGS on day +100. Eleven (65%) of these 17 had variants pre-allo-HCT and amongst the 88 patients with no variants post allo-HCT, 41 (47%) had detectable variants pre allo-HCT. There was no significant difference in baseline characteristics between patients with detectable variants at day+100 versus those who did not except for a higher KPS in patients with no variants at Day +100 of 90 (60-100) vs. 80 (60-100) (p=0.003). At a median follow up of 1.4 years (0.1-5.5), presence of a variant at day +100 was associated with inferior 4-year OS (32% vs. 69%, p&amp;lt;0.001) and higher relapse risk (64% vs. 23%, p&amp;lt;0.001). In univariate models, a lower KPS and presence of variants post allo-HCT were significantly associated with inferior OS, high relapse risk and worse PFS. Presence of variants pre allo-HCT was associated with an inferior PFS but did not impact OS or relapse risk. In multivariate models, KPS remained significant for OS, PFS and NRM; presence of variants at day +100 post allo-HCT approached significance for OS (p=0.06) and PFS (p=0.08) and was significant for relapse risk (p=0.002) (Table1) (Figure 1). Data regarding longitudinal evolution of variants and impact of individual variants on long term outcomes will be included at the time of presentation. Conclusion: These results indicate that presence of detectable somatic variants at day +100 is associated with poor long-term outcomes and predicts for high risk of disease relapse. Longitudinal monitoring of somatic variants via NGS should be consistently incorporated in the management of patients with high-risk AML and MDS undergoing allo-HCT. Patients with detectable somatic variants post allo-HCT should be considered for additional intervention to mitigate relapse risk.