High Risk Of Central Nervous System Relapse Research Articles

Deciphering Transcriptomic and (Epi)Genetic Signatures of Central Nervous System Infiltration in Patients Diagnosed with Diffuse Large B-Cell Lymphoma

Introduction Central Nervous System (CNS) involvement in Diffuse Large B Cell Lymphoma (DLBCL) is a rare complication with bad prognosis. The CNS Prognostic Index is employed to categorize patients at a high risk of CNS relapse; however, its effectiveness is not accurate. The discovery of precise biomarkers for predicting CNS involvement in DLBCL patients remains unmet. Our objective was to characterize the immune, transcriptomic, genomic and epigenomic hallmarks of systemic tumors at diagnosis of patients who later experienced relapse in the CNS. By exploring these biological profiles, we sought to gain valuable insights into the underlying mechanisms and potential biomarkers associated with CNS relapse in DLBCL. Methods We conducted a retrospective study including 38 patients diagnosed with nodal DLBCL who experienced relapse within the first two years after diagnosis. Among these patients, 12 individuals relapsed specifically in the CNS, while 26 relapsed in systemic sites. As a control group, we included 21 patients who did not relapse. DNA and RNA were extracted from FFPE tumor samples collected at diagnosis. To evaluate immune cell infiltration, we utilized the nCounter PanCancer Immune Profiling Panel (Nanostring); cell-of-origin (COO) was determined using the Lymph2Cx assay. Transcriptomic profiles were generated by bulk RNA sequencing and mutational analysis was performed using a custom targeted NGS panel, which included the most frequently mutated genes observed in lymphoid neoplasms. Methylation profiles were obtained using the Illumina Infinium MethylationEPIC Array 850K. Results Immune profiling analysis showed cell composition was not significantly different between groups; however, we observed distinct immune gene expression patterns at diagnosis in patients who experienced CNS relapse. Multiple genes were overexpressed in the CNS-relapsed group compared to non-relapsed group, which encompassed various functional categories including chemokine signaling such as IL7R (FC=2; P=0.05) and CCR6 (FC=3.4; P=0.01); adhesion like VCAM1 (FC=1.6; P=0.03) and ITGA4 (FC=2.2; P=0.006); and immune regulation such as CD1A (FC=4.8; P=0.001), LTB (FC=3.3; P=0.009) and BTLA (FC=2.3; P=0.02) (Fig.1A). The ITGA4 gene also presented higher expression levels in the CNS-relapsed group when compared to both systemic-relapsed and non-relapsed groups combined (FC=1.7; P=0.03). No significant differences were observed in the COO classification between groups. Whole-genome transcriptomic data revealed enrichment in gene sets associated with proliferation and survival in the CNS-relapsed group (Fig.1B). Analysis of genetic alterations indicated that patients with CNS relapse exhibited an increased mutation load and frequency in PIM1, IGLL5, and KMT2D genes. Finally, analysis of the CNS relapse-related epigenome showed 343 differentially hypomethylated CpG sites compared to both systemic and non-relapsed groups together, affecting a total of 211 genes. Pathway enrichment analysis of these genes revealed a link between CNS infiltration and cell migration and locomotion. Conclusions Tumors from DLBCL patients that will relapse in the CNS present a higher chemokine, adhesion and proliferation signatures at diagnosis. Of notice, BTLA, CCR6 and IL7R proteins have been previously reported to be implicated in B cell entry into the CNS in B-cell malignancies. Interestingly, patients with CNS relapse demonstrated significant overexpression of the ITGA4 gene, which encodes the integrin α4 subunit (CD49d) of the Very Late Antigen-4. Engagement between CD49d on B cells and its endothelial ligand VCAM-1 is required for migration of these cells across the blood-brain barrier. In fact, Natalizumab (anti-CD49d mAb) is administered in multiple sclerosis to impede entrance and accumulation of B cells in the brain. Initial experiments in mice have shown increased expression of CD49d in lymphoma B cells that have infiltrated the brain, compared to those in the spleen. Herein, we have demonstrated that DLBCL cells at diagnosis already own specific transcriptomic and (epi)genetic hallmarks that could confer a higher capacity to infiltrate the CNS. Validation of these findings in larger cohorts of patients could improve selection of patients with an increased risk of CNS involvement in need of prophylactic CNS-directed therapies at diagnosis.

RCHOP Plus High-Dose Methotrexate As First-Line Therapy in Large B-Cell Lymphoma with Testis Involvement

Primary testicular lymphoma (PTL) and diffuse large B-cell lymphoma with secondary testicular involvement (DLBCL-T) are rare subtypes of lymphomas associated with poor prognosis and a high risk of central nervous system (CNS) relapse. The optimal CNS prophylaxis strategy for these subtypes remains uncertain. High-dose methotrexate (HD-MTX) is debated for CNS prophylaxis, but its efficacy in this setting is unknown. This study aimed to retrospectively analyze the use of HD-MTX in combination with chemotherapy (R HD-MTX CHOP) as frontline treatment for PTL and DLBCL-T and to compare the biological characteristics of these two forms of testicular involvement. Data from patients who received R HD-MTX CHOP as first-line treatment for DLBCL-T or PTL between 2010 and 2020 were collected retrospectively. The study included 15 patients, 5 with PTL and 10 with DLBCL-T. The overall response rate was 86%, with 73% of patients achieving complete remission. Treatment-related adverse events were generally manageable, with febrile neutropenia being the most common. Two patients experienced CNS relapse, both from the DLBCL-T subgroup, with a median time of 10.7 months from diagnosis to CNS relapse. None of the PTL patients receiving HD-MTX experienced relapse during the median follow-up of 6.08 years (Figure 1A), compared to 8/10 DLBCL-T (p=0.007). All five PTL cases had a non-germinal center phenotype, while 7 out of 10 DLBCL-T cases were non-germinal center. One DLBCL-T case exhibited high-grade lymphoma. Myc expression was positive in 3 out of 10 patients assessed, of whom all were double expressors. Bcl-2 expression was positive in all 13 assessable patients, while Bcl-6 expression was positive in 6 patients. Myc, Bcl-2, and Bcl-6 rearrangements were assessed in 10 patients and were present in 1 patient who was found to have triple-hit lymphoma. No other patient had double-hit lymphoma or any significant rearrangement. Polysomy of Myc, Bcl-2, and/or Bcl-6 was found in 2 patients. PDL1 expression was observed in one out of six patients analyzed, while no PD1 expression was detected. In 8 out of 15 patients with available tissue material, next-generation sequencing using a panel targeting 43 lymphoid genes was performed. Among these 8 patients, 87% exhibited gain-of-function mutations in MYD88 (MYD88 L265P), and 62% had missense mutations in CD79B at position Y196. Multiple mutations in the PIM1 gene, a known target of aberrant somatic hypermutation, were also observed in 7 patients. Non-recurrent mutations were detected in various genes, including PRDM1, CD58, B2M, CREBBP, CIITA, CARD11, CDKN2A, EP300, CCDND3, FOXO1, IRF4, NFKBIE, and TCF3 (Figure 1B). Ig rearrangement was analyzed in 4/9 patients with available DNA. All 4 were clonal, with distinct but mutated VH segments (sequence identity between 81 and 89%). This study suggests that HD-MTX in combination with RCHOP chemotherapy is highly effective in preventing CNS relapse in PTL but less so in DLBCL-T. DLBCL-T had a higher risk of CNS relapse and poorer outcomes compared to PTL. Further studies are needed to determine the optimal timing and sequence of HD-MTX in DLBCL-T, as well as alternative treatment approaches. PTL and DLBCL-T have distinct clinical presentations and responses to frontline chemotherapy with HD-MTX prophylaxis. PTL may benefit from HD-MTX in preventing relapse, while alternative treatments should be explored for DLBCL-T. Future studies should consider PTL and DLBCL-T as separate entities to better understand their characteristics and optimize treatment strategies.

CNS Prophylaxis in Adult ALL Patients after Stem Cell Transplantation: An EBMT Survey on General Practice

Introduction Allogeneic hematopoietic stem cell transplantation (HSCT) is an effective treatment for acute lymphoblastic leukemia (ALL) resulting in long-term remission. Despite advances in therapy, disease progression remains the major cause of mortality following HSCT accounting for 20-50% of all deaths. The central nervous system (CNS) is the most common extra-medullary site of disease progression after transplant in ALL. The established practice of CNS prophylaxis for ALL has largely been modeled in the pediatric population, given the higher incidence of ALL in this age group compared with adults. Although the use of CNS prophylaxis as part of the upfront treatment for ALL has led to significant decreases in CNS relapse and improved outcomes overall, the routine use of post-HSCT prophylactic CNS therapy as a strategy to prevent CNS relapse after transplant in adult patients is still controversial. Studies that utilized post-HSCT CNS prophylaxis have reported disparate results and there is no generalized consensus regarding the use of post-transplant CNS prophylaxis to prevent relapse. Methods In order to assess the current practice of post-HSCT prophylactic CNS therapy in preventing CNS relapse in ALL patients, we carried out a survey among EBMT centres to describe intrathecal (i.t.) prophylaxis or irradiation in HSCT for ALL in both patients with or without CNS manifestations at any time of disease (first or second complete remission [CR1, CR2] and relapsed/refractory [R/R] ALL). EBMT centres were asked whether they usually give i.t. prophylaxis or cranial irradiation before and after HSCT, and which drugs they use. Results Of 410 invited centres, 55 (13%) replied to the survey. Tables 1 shows the number of centres which use i.t. prophylaxis or cranial irradiation. Most of the 55 centres used both pre-and post i.t. prophylaxis and triple prophylaxis (steroids, cytarabine [AraC] and methotrexate [MTX]) was the most frequently adopted. As expected in the pre-transplant phase, almost 70% of centres use i.t. chemotherapy irrespective of the phase of the disease or of the use of total body irradiation (TBI) as conditioning regimen. In the post-transplant phase, the rate of i.t prophylaxis varies according to disease phase, TBI use, and history of CNS involvement pre HSCT. In patients w/o history of CNS involvement in CR1, i.t. prophylaxis is given in 23.6% and 21.5% (with or w/o TBI use, respectively). Notably in CR2 pts, i.t. prophylaxis is given in 20% of cases if the conditioning regimen includes TBI, and in 74.5% of cases if TBI is not used; 32.7% and 46.9% R/R pts (with or without TBI use, respectively) are given i.t. prophylaxis. In the setting of patients with history of CNS involvement in CR1, i.t. prophylaxis is given in and 30.9% and 38.2% (with or without TBI use, respectively); in CR2 pts, i.t. prophylaxis is given in 38.9% of cases if the conditioning regimen does not include TBI, and in 29.1% of cases if TBI is used; 38.9% and 45.3% R/R pts (with or without TBI use, respectively) are given i.t. prophylaxis. Pre-transplant cranial irradiation is planned in less than 10% of centres in CR1 and CR2 patients without CNS involvement, irrespective of the use of TBI in the conditioning regimen, while it is used in 22.4% and 25% of patients with R/R disease with or without TBI use for transplant, respectively. In the setting of patients with CNS involvement, among those in CR1 and CR2, approximately 30% receive pre-transplant cranial irradiation irrespective of TBI use, while 32.7% and 34.6% of patients receive cranial irradiation (with or without TBI use, respectively). Its use after transplant is uncommon irrespective of disease status at treatment. Conclusions CR2 pts (without CNS involvement) seem to be at higher risk of CNS relapse if TBI is not included in the conditioning regimen. R/R pts are always considered at higher risk for CNS relapse if TBI is not included in the conditioning regimen. Cranial irradiation before treatment is used in almost 1 out of 3 pts with CNS involvement despite the use of TBI as the conditioning regimen, and 1 out 4 R/R pts without CNS involvement at transplant. The rate of cranial irradiation after transplant is extremely low, irrespective of diseases status, previous CNS involvement or TBI use. In conclusion, the use of i.t. prophylaxis after HSCT in patients with or without CNS involvement is variable among European transplant centres, also in the era of novel therapies for patients with ALL.

Diffuse Large B-Cell Lymphoma CNS Relapse Prophylaxis with Intrathecal or High-Dose Intravenous Methotrexate

Introduction: Central nervous system (CNS) relapse is a relatively infrequent but often fatal complication of the most common subtype of non-Hodgkin lymphoma, diffuse large B-cell lymphoma (DLBCL). Median overall survival (OS) after DLBCL relapse in the CNS is about 4 months. Despite identifying patients at high risk of developing CNS relapse using the CNS international prognostic index (CNS-IPI) score, it has been difficult to validate any specific strategy. Various chemotherapies and administration methods have been tested. Thus far, only the addition of rituximab to chemotherapy has yielded significant results. Our objective is to determine if administering prophylactic chemotherapy is efficacious in preventing DLBCL relapse in the CNS. Methodology: We collected retrospective data for patients with newly diagnosed DLBCL treated with rituximab and anthracycline-based chemotherapy from 2010 to 2020 in the Northwell Health system to determine the efficacy of CNS prophylaxis. Patients with CNS disease at diagnosis, primary testicular lymphoma, primary mediastinal large B-cell lymphoma, and HIV-associated lymphoma were excluded from this study. CNS prophylaxis was defined as receiving at least two doses of prophylactic chemotherapy, whether intravenous or intrathecal. Follow up for at least one year after diagnosis was required for inclusion. Overall survival (OS) was defined as the time difference between the date of definitive diagnosis to death or last date of contact. Other potential prognostic factors including double hit status and cell of origin, germinal center B-cell (GCB) vs. non-germinal center B-cell (non-GCB), were also evaluated. Pearson's chi-square analysis was used to compare the rate of DLBCL relapse in the CNS based on whether patients received CNS prophylaxis. Low risk was defined as CNS-IPI score 0 to 3 and high risk as CNS-IPI score 4 to 6. Kaplan-Meier analysis with log-rank (Mantel-Cox) testing was used to determine if any significant OS benefit was observed for the low and high-risk groups based on CNS-IPI score. Results: Of the 437 charts reviewed, 127 were eligible for inclusion. Most patients were male (56.7%). Median age was 69 years and median Eastern Cooperative Oncology Group (ECOG) performance status was 1. Most cases were non-GCB (44.9%, as 25% of cases were missing data) and not double hit (85%). Of the 35 patients at high risk for CNS relapse, 27 (77%) received prophylaxis. Intrathecal methotrexate (IT MTX) was given to 26 patients (96%) and high dose intravenous methotrexate (HD MTX) was given to 1 patient. CNS relapse occurred in 6 patients, of which 5 had a low-risk CNS-IPI score. One of the five patients in the low-risk group and the one patient in the high-risk group that had CNS relapse received prophylaxis. No significant difference in overall relapse rates were observed based on whether prophylaxis was given, X 2 (1, N = 127) = 0.30, p = .59. Kaplan-Meier analysis showed no difference in OS after stratification of patients by CNS-IPI score into the high-risk ( p = .50) and low-risk ( p = .24) groups. HD MTX was not administered frequently enough to determine its efficacy. Neither cell of origin (X 2 (1, N = 95) = 2.95, p = .086) nor double hit status (X 2 (1, N = 127) = 1.512, p = .22) had any significant effect on OS. Conclusions: We did not observe any clear benefit for administering IT MTX to prevent DLBCL relapse in the CNS. Most of the CNS relapse events occurred in the low-risk group, even though 8 patients in the high-risk group did not receive any CNS prophylaxis. This study did not have sufficient power to make a definitive conclusion. As CNS relapse is a rare event, a much larger sample size is required to determine the true efficacy of CNS prophylaxis. Non-GCB cell origin and positive double hit status are not included in the CNS-IPI score but their potential association with risk of DLBCL relapse in the CNS is understudied. Future studies should build upon these findings.

The Role of Prophylactic Chemotherapy for the Prevention of Central Nervous System Relapse in Patients with Large B Cell Lymphoma: A Meta-Analysis

Introduction: Central nervous system (CNS) relapse in large B cell lymphoma (LBCL) is a rare, but catastrophic event associated with poor prognosis without an effective standard prophylactic strategy. Intravenous and/or intrathecal chemotherapy have been proposed for patients at high risk for CNS relapse (i.e., CNS-IPI of 4 or greater) with mixed results due to the lack of prospective trials comparing different approaches. Large retrospective cohort studies have challenged the value of CNS prophylaxis. We performed a systematic review and meta-analysis (MA) assessing the role of chemoprophylaxis in preventing CNS relapse for LBCL patients treated with chemoimmunotherapy. Methods: A systematic literature review was conducted using the major online databases, including English language studies published from 2011 until 2022. Data were pooled from the studies with a comparator group using the random effects model to report odds ratio (OR) and 95% confidence intervals (95% CI). Data from single-arm studies were pooled using the random effects model to report the pooled proportion with 95% CIs. Results: There were 16 studies included in the MA (12 retrospective and 4 prospective) assessing the role of CNS prophylaxis in a total of 11,530 patients. The incidence of CNS relapse appeared to be higher among patients who received CNS chemoprophylaxis (n=2108) compared with patients without chemoprophylaxis(n=9422) (OR 1.70, 95% CI 1.10-2.61) (figure 1). Among the single-arm studies, the pooled proportion of the incidence of CNS relapse, isolated CNS relapse and secondary CNS relapse was 5% (95% CI 4%-7%), 5% (95% CI 4%-7%), and 1% (95% CI 0%-2%), respectively. Results are confounded by the retrospective design of most studies, different types of chemoprophylaxis and heterogeneous patient population. Discussion: This systematic review and MA demonstrated consistent rates of CNS relapse as seen in prior large cohorts, and did not show evidence for the use of chemoprophylaxis in patients with LBCL to prevent CNS relapse. Given the scarcity of high quality data due to the absence of prospective trials and the lack of motivation by multiple stakeholders to develop these type of studies, the totality of evidence grouped in this MA constitutes one of the most robust datasets arguing against chemoprophylaxis for prevention of CNS relapse in patients with LBCL. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Low Incidence of Central Nervous System (CNS) Relapse of Diffuse Large B-Cell Lymphoma despite Limited Use of Intrathecal Prophylaxis

Diffuse large B cell lymphoma (DLBCL) is the commonest sub type of non-Hodgkin's lymphoma (NHL) accounting for 30–50 % of NHL cases. Around 2% to 10% of patients with diffuse large B-cell lymphoma (DLBCL) experience central nervous system (CNS) relapse after initial therapy which is associated with a poor prognosis and most often a fatal outcome. The incidence of CNS relapse can vary from <1% in younger, good-risk patients, to around 30% in patients with multiple risk factors, however, the relapse risk was reported to be lower in the rituximab era in some studies. Moreover, optimal modality of CNS prophylaxis remains to be defined, with both systemic and intrathecal (IT) chemotherapy being widely used. As the incidence of CNS relapse and type of prophylaxis used varies in different reports, it is important to study this risk in different populations to implement optimal prophylaxis strategies. The Objectives of this study was to evaluate the incidence of CNS relapse in DLBCL patients at our institution and to study risk factors and the type and role of CNS prophylaxis. We retrospectively analyzed patients diagnosed with DLBCL at King Khalid University Hospital, Riyadh, from January 2011 to June 2019. Data were collected from computerized hospital information system and from the files of the patients. Variables studied included age at diagnosis, stage at diagnosis, international prognostic index (IPI) and CNS-IPI score, site(s) of extra-nodal involvement, type of chemotherapy received, CNS prophylaxis and CNS relapse. CNS prophylaxis was administered on the basis of presence of high-risk features like presence of ≥2 extranodal sites, involvement of bone marrow, bone, testes, nasopharynx and paranasal sinuses. Patients with presence of CNS involvement at diagnosis and primary CNS lymphoma were excluded. A total of 101 patients were diagnosed with DLBCL during the study period. There were 58 males and 43 females with a median age of 56 (range: 16-87) years. Ann Arbor stage of I-IV was assigned in 9, 21, 17 and 50 patients, respectively. The lung was the most common extranodal site involved in 27 (26.7%) patients, and liver and bone marrow involved in 20 (19.8%) patients each. Gastrointestinal tract was involved in 9 (8.9%) patients, kidneys in 5 (4.95%), breast in 4 (4%), and testis and adrenal in 2 (2%) patients each. Twenty-five (24.75%) patients had high risk CNS-IPI score, 44 (43.5%) had intermediate risk score and 32 (31.7%) had low risk score. Ninety-four (93%) patients received R-CHOP chemotherapy while rest of the patients received other types of chemotherapy, mostly a milder regimen (R-CVP), because of comorbidities and poor performance status. Sixteen patients received CNS prophylaxis, which was IT methotrexate (MTX) ± cytarabine/hydrocortisone in all patients. Nine of 25 (36%) patients with high-risk CNS-IPI score did not receive CNS prophylaxis. After a median follow up of 36 months (range 4-114), 2 (2%) patients developed CNS relapse and died shortly after this diagnosis. Both the patients with CNS relapse had high risk CNS-IPI score and did not receive CNS prophylaxis. CNS relapse of DLBCL was uncommon in this patient population despite limited use of IT CNS prophylaxis in high-risk patients. Low incidence of CNS relapse in many high-risk patients despite limited use of IT prophylaxis may be related to rituximab use and/or other factors. Our data indicate that IT CNS prophylaxis may be adequate for DLBCL patients at high risk of CNS relapse.

ABCL-455 Multicenter Retrospective Analysis of Single-Route Prophylaxis in Aggressive B-Cell Lymphomas

Relapses involving the central nervous system (CNS) are uncommon among patients with diffuse large B-cell lymphoma (DLBCL) but carry very poor prognosis. Prophylaxis is heterogeneously prescribed around the time of frontline therapy, with no clear standard of care in terms of recipient selection or route of administration. We retrospectively evaluated 1162 adult patients across 21 US academic centers with DLBCL or similar histologies who received single-route CNS prophylaxis as part of frontline chemoimmunotherapy between 2013-2019. Primary endpoint was CNS relapse rate. Secondary endpoints included PFS, OS, and treatment-related toxicities following frontline and salvage therapies. Prophylaxis was administered intrathecally (IT) in 894 (77%) and using systemic high-dose methotrexate (HD-MTX) in 236 (20%); 32 patients (3%) switched route due to toxicity and were assessed separately. By CNS-International Prognostic Index (IPI), 18% were considered low-risk, 51% moderate, and 30% high. Double-hit lymphoma (DHL) was confirmed in 243 of 866 evaluable patients (21%). Sixty-four patients (5.7 %) had CNS relapse, after median 7.1 months from diagnosis, including 15 of 64 (23%) within the first 6 months. There was no significant difference in CNS relapse between IT and HD-MTX recipients (5.4 vs 6.8%, p=0.40), including after propensity score matching to account for differences between respective recipient groups. Weighting by CNS-IPI, expected versus observed CNS relapse rates were nearly identical (5.8 vs 5.7%). Testicular involvement was associated with high risk of CNS relapse (11.3%) despite most having lower CNS-IPI scores. DHL did not significantly predict for CNS relapse after single-route prophylaxis, including with adjustment for treatment regimen and other factors. Median OS following CNS relapse was 6.2 months (IQR 2.9-24.6) and was significantly shorter among patients achieving less than CR to first salvage therapy (HR 3.39, 95% CI 1.76-6.54, p=0.0003). Additional analyses of outcomes following CNS relapse will be presented. This large study of CNS prophylaxis recipients with DLBCL found no significant difference in CNS relapse rates between routes of administration. Relapse rates among high-risk subgroups remain elevated; treatments following CNS relapse were heterogeneous, with poor outcomes for the vast majority of patients. Reconsideration of SCNSL prophylaxis and treatment strategies is of critical need.

Flow Cytometric Detection of Malignant Blasts in Cerebrospinal Fluid: A Biomarker of Central Nervous System Involvement in Childhood Acute Lymphoblastic Leukemia.

Despite the excellent prognosis for children and adolescents with acute lymphoblastic lymphoma (ALL), the involvement of the central nervous system (CNS) represents a major therapeutic challenge. Patients who develop CNS relapse have a very poor prognosis, and since current methods cannot reliably identify patients with CNS involvement or patients at high risk of CNS relapse, all children with ALL receive CNS-directed treatment. The current golden standard for detecting CNS involvement is the assessment of cytomorphology on cytospin slides of cerebrospinal fluid (CSF). This technique is inadequate due to low sensitivity and reproducibility. Flow cytometric analysis of CSF represent a novel, highly specific and sensitive technique for the detection of leukemic cells in the CNS. In prospective studies, CSF flow cytometry demonstrated two to three times higher rates of CNS involvement at diagnosis of childhood ALL than conventional cytospin, and especially demonstrated superior sensitivity in detecting low-level CNS disease. CNS involvement determined via flow cytometry has been linked to a higher risk of CNS relapse and poor outcomes in several studies. In this review, we discuss the central analytical concepts of CSF flow cytometry and summarize the current evidence supporting the use of flow cytometric detection of malignant blasts as a biomarker of CNS involvement in childhood ALL.

Predictive impact of soluble interleukin-2 receptor and number of extranodal sites for identification of patients at very high risk of CNS relapse in diffuse large B-cell lymphoma.

There remains an unmet clinical need to identify which patients with diffuse large B‐cell lymphoma (DLBCL) would benefit from central nervous system (CNS) prophylaxis, due to the low positive predictive value (PPV; 10%–15%) of the currently available predictive models. To stratify patients at high risk of developing CNS relapse, we retrospectively analyzed 182 patients with DLBCL initially treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R‐CHOP), or a R‐CHOP‐like regimen. Among them, 17 patients relapsed with CNS involvement, and the 2‐year rate of CNS relapse was 7.9%. Upon carrying out multivariate analysis, ≥3 extranodal sites and elevated soluble interleukin‐2 receptor (sIL‐2R) levels at diagnosis were identified as independent risk factors for CNS relapse. The 2‐year and 3.5‐year rates of CNS relapse were 57.1% and 78.6%, respectively, in patients with both elevated sIL‐2R and ≥3 extranodal sites. Furthermore, combined use of these risk factors of both elevated sIL‐2R and ≥3 extranodal sites resulted in a high PPV (71.4%), negative predictive value (93.1%), and overall accuracy (92.3%) for undergoing CNS relapse. In conclusion, we propose a simple and valuable tool to predict patients with DLBCL at very high risk of CNS relapse.

Cerebrospinal fluid flow cytometry and risk of central nervous system relapse after hyperCVAD in adults with acute lymphoblastic leukemia.

Potential involvement of the central nervous system (CNS) by acute lymphoblastic leukemia is typically evaluated by a conventional cytospin (CC) of cerebrospinal fluid (CSF). Multiparameter flow cytometry (MFC) is generally more sensitive and specific than morphology, but data to guide its use versus CC are limited. This study identified 92 patients who had MFC performed on their initial CSF specimen and received at least 4 cycles of hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with methotrexate and cytarabine (hyperCVAD) as their initial treatment. Eighteen (20%) were CSF+ by MFC at the baseline, and only 6 of these patients were positive by CC. In contrast, 0 of 51 patients who were negative by MFC and had CC available were positive by CC. Despite the receipt of significantly more intra-CSF chemotherapy (P < .001), the cumulative incidence of CNS relapse by MFC was 22% among CSF+ patients versus 5% among those who were CSF- (P = .044). No such association was observed between CNS relapse and CC results (P = .42). None of the 74 CSF- patients became CSF+ during their initial treatment despite being tested a median of 5 times (range, 2-10). CSF positivity by MFC was the factor most strongly associated with CNS relapse in a series of univariate Cox models (hazard ratio, 3.7; P = .067). The initial CSF status by MFC had no significant impact on overall or event-free survival. MFC of CSF is superior to CC of CSF in identifying adults at high risk for CNS relapse after treatment with hyperCVAD. Surveillance of CSF by MFC has limited utility.

Impact of Double Hit Lymphoma and Cell of Origin in the Risk of Central Nervous System Relapse in Patients with Newly Diagnosed Diffuse Large B-Cell Lymphoma

Introduction: Central nervous system (CNS) relapse is an uncommon but devastating complication occurring in about 2-10% of patients with diffuse large B-cell lymphoma (DLBCL). The CNS-IPI is a validated prognostic tool used to identify patients at high risk of CNS relapse. MYC and BCL2/BCL6 rearrangements (double-hit lymphoma- DHL) and non-GCB (NGCB) cell of origin may be at higher risk of CNS relapse. However, the ability of these molecular data to refine CNS-IPI risk prediction has not been assessed. In this study, we aimed to describe the impact of DHL and NGCB cell of origin in the incidence of CNS relapse in patients with newly diagnosed DLBCL.Methods: A retrospective review was conducted to identify patients with newly diagnosed DLBCL from 01/01/2002 - 06/30/2015 using the University of Iowa/Mayo Clinic Lymphoma Molecular Epidemiology Resource database. Patients with primary CNS lymphoma or with CNS involvement at diagnosis were excluded. All patients received chemoimmunotherapy. Clinical, biological, laboratory and radiological data were abstracted including the occurrence of CNS relapse. CNS IPI risk score categories were defined as low- (≤1) intermediate- (2-3) and high-risk (≥4) as originally described (Schmitz et al, JCO 2016). Cell of origin (COO) classification into GCB and non-GCB subtypes was performed using Hans algorithm and/or NanoString data. Characteristics between groups were compared using Kruskal-Wallis or Chi-squared test as appropriate. Survival analysis was performed using Cox proportional hazards model and the Kaplan Meier method. Statistical analysis was performed using SAS version 9.4M5 and R version 4.0.3.Results: We identified a total of 1,360 patients with newly diagnosed DLBCL. Patients had a median age of 62 years (range 18-93 years), were predominantly male (56%), had a performance status <2 (84%), had stage III/IV disease (61%) and an elevated LDH (56%) at diagnosis. Fluorescent in situ hybridization data was present for 65% of patients. Among patients with available data, DHL and NGCG COO represented 2.8% and 36% of the cohort, respectively. CNS IPI high- and intermediate-risk categories were present in 12.4% and 52% of the patients, respectively. R-CHOP was the most common upfront chemotherapy (n=980, 72%).The median follow-up for the entire cohort was 84.9 months (IQR: 58.9-120.9). Overall, 50 patients (3.6%) had a CNS relapse during the study period. Lymphoma relapsed in the CNS in 3.0% (95% CI:2.1-4.4), 4.7% (95% CI: 3.4-6.3) and 4.9% (95% CI: 3.7-6.6)% of patients with CNS-IPI score of intermediate/high risk at 1, 3 and 5 years following the diagnosis of DLBCL. In patients with low risk CNS-IPI, 1.1% (95% CI: 0.4-2.5), 1.7% (95% CI: 0.9-3.4) and 1.7% (95% CI: 0.9-3.4) had a CNS relapse at 1, 3 and 5 years following DLBC diagnosis. Patients with CNS relapse were more likely to have elevated LDH (76% vs 56%, p=0.008), advanced stage (78% vs 61%, p=0.01), adrenal involvement (8% vs 2.4%, p=0.014) and have a CNS IPI intermediate risk (68% vs 51%), and high risk (16% vs 12.3%, p=0.014) at the time of initial diagnosis compared to patients without CNS relapse. Patients with CNS relapse had similar rates of DHL (4% vs 2.7%, p=0.17) and NGCB cell of origin (42% vs 36.2%, p=0.52) compared to patients without CNS relapse.In the multivariable analysis, the strongest predictors for CNS relapse were CNS IPI high risk (Hazard Ratio [HR]= 3.6, 95%CI= 1.4-9.7) and CNS IPI intermediate risk (HR= 3.15, 95%CI= 1.46-6.81). DHL and NGCB cell of origin were not associated with a significantly higher risk of CNS relapse (HR= 1.79, [95%CI=0.42-7.59] and HR= 1.26, [95%CI=0.62-2.57], respectively).Conclusion: CNS relapse was an uncommon occurrence in patients with DLBCL who were treated with chemoimmunotherapy. CNS IPI intermediate- and high-risk scores remain the strongest predictors of CNS relapse in patients with DLBCL after adjusting to biological high-risk variables including DHL and NGCB cell of origin. Larger studies are required to validate our findings due to the low incidence of CNS relapse in our cohort. [Display omitted] DisclosuresFarooq: Kite, a Gilead Company: Honoraria. Maurer: Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Morphosys: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Genentech: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Nanostring: Research Funding. Witzig: Karyopharm Therapeutics, Celgene/BMS, Incyte, Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene/BMS, Acerta Pharma, Kura Oncology, Acrotech Biopharma, Karyopharm Therapeutics: Research Funding. Habermann: Tess Therapeutics: Other: Data Monitoring Committee; Seagen: Other: Data Monitoring Committee; Incyte: Other: Scientific Advisory Board; Morphosys: Other: Scientific Advisory Board; Loxo Oncology: Other: Scientific Advisory Board; Eli Lilly & Co.,: Other: Scientific Advisor. Novak: Celgene/BMS: Research Funding.

Retrospective Review of the Safety and Efficacy of High-Dose Methotrexate for Prevention of CNS Relapse in Diffuse Large B-Cell Lymphoma at Kaiser Permanente- Northern California (Jan 2015 - June 2019)

Retrospective review of the safety and efficacy of high-dose methotrexate for prevention of CNS relapse in diffuse large B-cell lymphoma at Kaiser Permanente- Northern California (Jan 2015 - June 2019)Background: Central nervous system (CNS) relapse occurs in 10-12% of high-risk diffuse large B-cell lymphoma (DLBCL) patients. Prophylactic intravenous high-dose methotrexate (HD-MTX) is recommended by international guidelines to reduce this risk despite limited evidence to support such practice. Recent retrospective studies have cast doubt on the clinical benefit of such treatment. There is limited data on safety and efficacy of such treatment in a community oncology setting.Methods: We conducted a retrospective analysis of adults ≥ 18 years diagnosed with DLBCL treated with systemic therapy and HD-MTX as CNS prophylaxis at Kaiser Permanente Northern California from 1/2015 - 6/2019. We abstracted patient demographics, clinical information, treatment, toxicity, and health care utilization from the electronic health record. Descriptive statistics were used to evaluate patients' outcomes.Results: Of 33 patients (median age: 61; range: 23 - 81; age ≥ 60: 57.5%), most had stage IV disease (78.7%) and an ECOG performance status of 0 or 1 (66.5%). Patients with CNS-IPI score of 2-3 (intermediate-risk) was 30.3%, while higher CNS-IPI scores of 4-6 (high-risk) was 51.5%. Other patient characteristics include double hit lymphoma (12.1%), kidney/adrenal gland involvement (33%), and/or epidural involvement (24.2%). Most common therapies were R-CHOP (51.5%) and R-EPOCH (27.2%). The median number of HD-MTX doses was 3 (range 1-4). The median cumulative dose was 7 gm/m2 (range 3-10.5). With regards to the treatment schedule, 63.6% received HD-MTX intercalated with systemic chemotherapy and 36.4% received HD-MTX after completion of preplanned treatment. Overall, renal toxicity was the most common adverse side effect. The rates of grade 1, 2 and 3 renal toxicity were 12.1%, 9% and 6%, respectively. Other notable side effects experienced were neutropenic fever requiring hospitalization (27.2%) and grade 3 transaminitis (6%). No patients experienced grade 3 mucositis. The median duration of hospital stay was 12 days (range 4-37) and 12.1% required suspension of future HD-MTX. With a median follow up of 31.3 months (range: 0.79 - 58.4) 69.6% are alive and 15.1% had CNS relapse despite prophylactic HD-MTX.Conclusions:In this community oncology setting, patients with DLBCL who were deemed high risk for CNS relapse and received HD-MTX for prophylaxis experienced similar CNS relapse rate compared to those who did not in previous studies. Our findings are in line with recent retrospective reviews, which further support the lack of benefit of such prophylactic treatment. This study underscores the need for further research to prevent CNS disease and improved patient selection criteria for prophylactic treatment among high risk DLBCL patients. DisclosuresNo relevant conflicts of interest to declare.

Clinical Outcomes and CNS Relapse Risk in Patients with Primary Cutaneous DLBCL, Leg Type Treated in the Rituximab Era: Long-Term Follow-up of a Single-Center Experience

Clinical Outcomes and CNS Relapse Risk in Patients with Primary Cutaneous DLBCL, Leg Type Treated in the Rituximab Era: Long-Term Follow-up of a Single-Center Experience

Central nervous system (CNS) prophylaxis in antiCD20-CHOP treated DLBCL at intermediate to high risk for CNS relapse: A systematic review and meta-analysis.

CNS prophylaxis is commonly used in Diffuse Large B-Cell Lymphoma (DLBCL) patients with risk features for CNS relapse. This systematic review and meta-analysis compares CNS relapse rates with and without CNS prophylaxis, for patients at intermediate to high CNS relapse risk. Studies reporting CNS relapse risk category and CNS outcomes with and without CNS prophylaxis for antiCD20-CHOP treated DLBCL patients were included. 10 studies with 3770 patients at intermediate to high CNS relapse risk were analyzed. No significant difference in the pooled Absolute Risk Difference (ARD 0.01, 95 % CI -0.01 to 0.02, P = 0.61) or Risk (RR 1.22, 95 % CI 0.81-1.83, P = 0.34) was noted in patients with and without CNS prophylaxis. There were also no differences within pre-specified subgroups of IV Methotrexate or IT chemotherapy. However, the quality of evidence supporting these observations was low. A meta-analysis of individual patient data will help evaluate the benefit of CNS prophylaxis strategies.

Single-route CNS prophylaxis for aggressive non-Hodgkin lymphomas: real-world outcomes from 21 US academic institutions

AbstractProphylaxis is commonly used to prevent central nervous sy stem (CNS) relapse in diffuse large B-cell lymphoma (DLBCL), with no clear standard of care. We retrospectively evaluated 1162 adult patients across 21 US academic centers with DLBCL or similar histologies who received single-route CNS prophylaxis as part of frontline therapy between 2013 and 2019. Prophylaxis was administered intrathecally(IT) in 894 (77%) and using systemic high-dose methotrexate (HD-MTX) in 236 (20%); 32 patients (3%) switched route due to toxicity and were assessed separately. By CNS-International Prognostic Index (IPI), 18% were considered low-risk, 51% moderate, and 30% high. Double-hit lymphoma (DHL) was confirmed in 243 of 866 evaluable patients (21%). Sixty-four patients (5.7%) had CNS relapse after median 7.1 months from diagnosis, including 15 of 64 (23%) within the first 6 months. There was no significant difference in CNS relapse between IT and HD-MTX recipients (5.4% vs 6.8%, P = .4), including after propensity score matching to account for differences between respective recipient groups. Weighting by CNS-IPI, expected vs observed CNS relapse rates were nearly identical (5.8% vs 5.7%). Testicular involvement was associated with high risk of CNS relapse (11.3%) despite most having lower CNS-IPI scores. DHL did not significantly predict for CNS relapse after single-route prophylaxis, including with adjustment for treatment regimen and other factors. This large study of CNS prophylaxis recipients with DLBCL found no significant difference in CNS relapse rates between routes of administration. Relapse rates among high-risk subgroups remain elevated, and reconsideration of prophylaxis strategies in DLBCL is of critical need.

CNS Prophylaxis in DLBCL: A Ten Year Single-Center Review in the Rituximab Era

Introduction:The role of prophylactic treatment for central nervous system (CNS) relapse in DLBCL is not clearly established. The selection of patients (pts) and the optimal regimens, including choice of agents, timing of administration, dosing, route, etc., remain unclear. In an effort to develop a uniform approach to this strategy, we have reviewed the practice of CNS ppx in DLBCL at Memorial Sloan Kettering during 2004-2014.Methods:We retrospectively reviewed 1) all newly diagnosed pts with DLBCL from 2004-2014 who received CNS ppx, and 2) all pts with DLBCL who developed CNS relapse/progression during the same period. All pts were treated with rituximab-based chemotherapy. Prophylactic agents included methotrexate (MTX) and/or cytarabine (ara-C). Pts with CNS or ocular involvement upon presentation were excluded. All data was compiled and analyzed using SPSS (IBM).Results:Three hundred and three pts received CNS ppx. CNS-IPI (Schmitz et al. J Clin Oncol, 2016) classified pts as low (18.2%), intermediate (43.6%), or high risk (38.2%) for CNS relapse. Seventy-six percent of pts presented with stage IV disease and a mean of 2.1 EN sites, frequently involving bone (53.8%) (vertebrae specifically, 33.7%), lung/pleura (20.1%), GI tract (18.2%), sinuses (17.5%), testes (10.5%) and others.Thirty-five percent of pts had high risk CNS IPI scores and received ppx. Most frequently, pts received ppx due to the presence of EN disease (36.6%), and of these pts 66.4% had multiple EN sites involved. CNS ppx was also administered to pts with primary testicular (24), sinus (30), and breast (8) DLBCL in addition to pts with isolated bone (21) vertebrae (14), and GI tract (5) lesions. The remaining 3.6% of pts received ppx for other reasons including high risk molecular profiles or bulky disease.Intrathecal (IT) MTX alone was administered to 271 of 303 prophylaxed pts, and 17 (5.9%) developed CNS involvement. High dose intravenous (HD) MTX alone was given to 7 pts; 1 developed CNS involvement. IT MTX and IT ara-C were given to 10 pts; 1 developed CNS involvement. IT and HD MTX plus IT ara-C were given to 2 pts; 1 developed CNS involvement. Additional combinations can been reviewed in Table 1.Twenty pts (6.6%) failed CNS ppx, with a median (mdn) time from diagnosis to detection of CNS involvement of 12.7 months. No pts developed CNS disease while on first-line therapy. Of 20 pts, 11 had isolated CNS relapses (mdn= 8.9 months). 7 relapsed systemically with CNS involvement (mdn =26.8 months). Two had primary refractory disease with CNS involvement detected at 10.2 and 12.7 months. The difference in time to CNS relapse based on involvement pattern (leptomeningeal, parenchymal or both) or the context of CNS involvement (isolated CNS relapse vs systemic relapse with CNS involvement) was not statistically significant. The pt treated with HD and IT MTX and IT ara-C relapsed in the CNS at 3.5 months, significantly earlier than pts treated with IT MTX (mdn 12.7 mo, p=0.02), but notably received only 3 cycles of R-CHOP due to wound dehiscence.There were 776 DLBCL pts from the same time period who were not treated with ppx, and 25 (3.2%) developed CNS involvement. One pt relapsed after 48d during R-CHOP. Three additional pts had primary refractory disease with CNS involvement at a median of 5.2 months. Fifteen had isolated CNS relapses (mdn 8.5 months), and 6 had systemic relapses with CNS involvement (mdn 12.0 months). There was no significant difference in the time to CNS relapse comparing pts who received CNS ppx to pts who did not.Conclusions:In our study, pts with DLBCL at high risk for CNS relapse treated with rituximab-based chemotherapy developed CNS involvement after systemic therapy was complete. Administering CNS ppx concurrently with R-CHOP poses many challenges, often resulting in dose adjustments or delays in treatment. Our results suggest that CNS ppx can be delayed until the completion of R-CHOP without compromising the effects of ppx. [Display omitted] DisclosuresMoskowitz:Seattle Genetics: Consultancy, Other: Ad Board, Research Funding; Genentech BioOncology: Consultancy; Pharmacyclics: Research Funding; Celgene: Consultancy; Merck: Consultancy, Research Funding.

Central Nervous System Relapse in Diffuse Large B Cell Lymphoma—Predictors at Diagnosis

Background Central nervous system (CNS) relapse of diffuse large B cell lymphoma (DLBCL) is an infrequent outcome with very poor prognosis. Initial studies have identified risk factors for CNS relapse and the CNS international prognostic score ((CNS-IPI) (Schmitz et al, JCO 2016) has been validated in various cohorts. Biologic characteristics of the disease are not included in the derivation of this model. We sought to validate this risk factor model in our single center DLBCL population in search for additional disease - specific factors that could further improve prediction of CNS relapse.Methods The hematologic malignancies database of the University Hospitals Seidman Cancer Center was accessed to identify newly diagnosed DLBCL patients between 2002 and 2014. Patients with extra-nodal CNS involvement at diagnosis were excluded. Through retrospective chart review data, we identified patient and disease characteristics, and outcomes data including response, relapse and death was collected. Patients who underwent therapy and had follow up data were included for final analysis. Univariate Cox proportional hazards analysis was conducted on the risk factors and those reaching statistical significance (p < 0.05) were selected for inclusion in multivariate proportional hazards model to help identify predictors for CNS relapse. CNS IPI score was applied to our population and cumulative incidence (with death as competing risk) was used to estimate the incidence of CNS relapse with the Gray test performed for comparisons between groups.Results: Five hundred and twenty-four patients were included for final analysis. Median age in our cohort was 64 years, with 312 (59.5 %) patients above the age of 60 years. 322 (63 %) patients had stage (III-IV), and 220 patients (37%) had elevated LDH at diagnosis. Two hundred and eighty five patients had extra-nodal disease involvement at the time of diagnosis with 88 patients involving more than one site. Baseline patient and disease characteristics are listed in Table 1. Four hundred (76%) patients received R CHOP as first line therapy, 395 patients achieved complete remission with first line therapy. At a median follow up of 64 months, 187 patients died and 171 patients had relapsed.Twenty-one patients developed CNS relapse in the follow up period, at median of 8.2 months after treatment initiation (95% CI 6.2-9.6) months. Applying the CNS-IPI risk scoring among the evaluable patients, 149 patients (36%) were found to be low risk (0-1 factors), 222 patients (53%) were intermediate risk (2-3 factors) and 47 patients (9%) were high risk (4-6 factors) for CNS relapse. Univariate analysis showed advanced stage (stage III-IV), number of extra-nodal sites involved, liver involvement, non- GCB subtype, translocation t (14; 18) and body mass index were significantly associated with CNS relapse (p<0.05). In multivariate analysis, only non- GCB subtype and translocation t (14; 18) (p = 0.023 and 0.028 respectively) were significant. Table 2 summarizes the results of Cox proportional hazards analysis.We evaluated the cumulative incidence of CNS relapse in the high-risk group, defined as CNS-IPI >1, (n=269, 64%). The 2-year CNS relapse cumulative incidence was at 5.1 % (95% CI: 2.8- 9%) compared to 0% for patients with CNS IPI ≤ 1 (p=0.027) (Figure 1).Median survival after CNS relapse was 3.6 months (0 - 150.2 months). Overall survival from start of initial therapy was 16 months (95% CI 9.5 -81.9 months) for patients with CNS relapse vs 170 months (95% CI 120.3 months - not reached), p<0.001]. (Figure 2)SummaryPrognosis of CNS relapsed of DLBCL is very poor. CNS IPI score helps identify a cohort that may benefit from CNS prophylaxis, and may help avoid unnecessary diagnostic and therapeutic intervention in the low risk cohort, i.e., CNS- IPI score <1. Hepatic involvement at diagnosis may be an additional clinical characteristic associated with high risk of CNS relapse. Biological features including non-GCB subtype and translocation t (14; 18) are novel risk factors that should be considered in the development of future risk models. [Display omitted] DisclosuresMalek:Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Membership on an entity's Board of Directors or advisory committees; Celgene: Speakers Bureau. Cooper:Novartis: Research Funding. de Lima:Celgene Corporation: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees. Caimi:Seattle Genetics: Equity Ownership; Abbvie: Equity Ownership; Incyte: Equity Ownership; Celgene: Speakers Bureau.

A Higher Dose of Dasatinib May Increase the Possibility of Crossing the Blood–brain Barrier in the Treatment of Patients With Philadelphia Chromosome–positive Acute Lymphoblastic Leukemia

Dasatinib is a second-generation tyrosine kinase inhibitor with higher central nervous system (CNS) penetration compared with imatinib and nilotinib in in vitro studies. However, limited clinical data are available regarding the dosage and CNS penetration of dasatinib. The purpose of this study was to investigate the actual ability of dasatinib to cross the blood-brain barrier in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Plasma and cerebrospinal fluid (CSF) samples collected from Ph+ ALL patients treated with dasatinib were analyzed by using an LC-MS/MS assay. Orally administered dasatinib 100 mg once daily was well absorbed by the patient but penetrated poorly into the CSF. The use of a higher drug dosage (140 mg/d) may increase systemic drug exposure and enhance the penetration of dasatinib into the CSF. Based on this study, the use of a higher dosage of dasatinib (140 mg/d) is recommended in patients at high risk of CNS relapse or patients who need treatment for CNS leukemia. ClinicalTrials.gov identifier: NCT02523976.

Prophylaxis with intrathecal or high-dose methotrexate in diffuse large B-cell lymphoma and high risk of CNS relapse

Although methotrexate (MTX) is the most widely used therapy for central nervous system (CNS) prophylaxis in patients with diffuse large B-cell lymphoma (DLBCL), the optimal regimen remains unclear. We examined the efficacy of different prophylactic regimens in 585 patients with newly diagnosed DLBCL and high-risk for CNS relapse, treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or R-CHOP-like regimens from 2001 to 2017, of whom 295 (50%) received prophylaxis. Intrathecal (IT) MTX was given to 253 (86%) and high-dose MTX (HD-MTX) to 42 (14%). After a median follow-up of 6.8 years, 36 of 585 patients relapsed in the CNS, of whom 14 had received prophylaxis. The CNS relapse risk at 1 year was lower for patients who received prophylaxis than patients who did not: 2% vs. 7.1%. However, the difference became less significant over time (5-year risk 5.6% vs. 7.5%), indicating prophylaxis tended to delay CNS relapse rather than prevent it. Furthermore, the CNS relapse risk was similar in patients who received IT and HD-MTX (5-year risk 5.6% vs. 5.2%). Collectively, our data indicate the benefit of MTX for CNS prophylaxis is transient, highlighting the need for more effective prophylactic regimens. In addition, our results failed to demonstrate a clinical advantage for the HD-MTX regimen.

Effectiveness of intravenous high-dose methotrexate for prevention of relapse in patients with DLBCL.

e19562 Background: Central nervous system (CNS) relapse develops in 2-10% of patients with diffuse large B cell lymphoma (DLBCL) and has an adverse prognosis. Tools like IPI and CNS-IPI scores identify patients at high risk of systemic or CNS relapse based on the presence of established risk factors ( Schmitz et al. JCO 2016). International guidelines propose prophylactic intravenous high-dose methotrexate (HD-MTX) for patients at high risk of CNS relapse; however, limited data is backing this approach. Methods: We conducted a retrospective review of newly diagnosed DLBCL patients aged 18-75 years treated with curative intent at large academic medical centers in Riyadh, Saudi Arabia, between 2015-2018. Patients who were planned for CNS HD-MTX after cycles 2, 4, and 6 of R-CHOP and received at least one HD-MTX cycle were included. Results: We identified 35 DLBCL patients who received at least one R-CHOP cycle with one cycle of HD-MTX. The median IPI and CNS-IPI score were 3, (range = 0-4) and 3, (range = 0-5), respectively. The median number of R-CHOP cycles received was 6 (range 3-6) and HD-MTX 3 (range 1-6). The overall response rate was 91%, with 3 (9%) primary refractory patients per interim evaluation on cycle 3 of R-CHOP. Achieving complete remission after six cycles of RCHOP was noted in 80%, with four additional patients showed residual disease at the end of treatment evaluation. The entire cohort's overall survival was not reached, and five years estimated survival is 75%. With a median follow-up duration of 37.3 months, none of the patients relapsed after achieving CR at the end of treatment evaluation. The risk of systemic or CNS relapse in our cohort was 0%. In restricting the analysis to CNS-IPI of ≥ 4, a total of 13 patients with a median follow-up of 42 months were included; four patients did not achieve CR by the end of treatment, while nine patients continue to be in CR without any evidence of relapsed disease. Conclusions: High-dose methotrexate with high-intensity chemoimmunotherapy (R-CHOP) seems to be associated with an improvement in the expected rate of CNS relapse. Our data set is small, and a more extensive study evaluating HD-MTX's effectiveness in high-risk DLBCL is warranted.[Table: see text]