Significant Difference In PFS Research Articles

CTNI-14. RADIOTHERAPY VERSUS TMZ FOR HIGH-RISK LOW-GRADE GLIOMA. FINAL RESULTS AFTER MEDIAN FOLLOW-UP OF 13 YEARS OF PHASE III EORTC/NCIC-CTG/TROG/MRC-CTU (EORTC 22033-26033) STUDY

Abstract BACKGROUND We previously reported on progression-free survival of our randomized phase 3 trial [Lancet Oncol. 2016;17:1521-1532]. Here we report results of long-term follow-up (FU) including overall survival (OS) and molecular subgroup analyses. METHODS 487 patients were randomized between 2005-2012 to either standard radiotherapy (RT, 50.4 Gy/ 28 fractions) or primary dose-dense temozolomide [TMZ] chemotherapy (75 mg/m² daily x 21/28 days, up to 12 cycles). Treatment at progression was at investigators discretion and commonly included cross-over to the alternative treatment modality. RESULTS At a median follow-up of 13 years, 68% of patients had died. Median age at inclusion was 45 years (range 18-75), 96% had a performance status of 0-1. There was no significant difference in PFS nor OS: PFS was 3.6 years (95% CI: 3.0-4.1) and 3.1 years (95% CI: 2.7-3.6), HR 1.12 (95% CI: 0.92-1.36); OS 6.6 years (95% CI: 5.8-7.5) and 8.0 years (95% CI: 6.9-9.1), HR 0.87 (95% CI: 0.69-1.09), for RT or TMZ, respectively. Subgroup analyses were performed for patients when available tissue allowed for molecular analyses (n=351/487,73%). In astrocytoma, IDHmt/1p/19q non-codeleted (n = 178), median OS with RT was 6.6 years (95% CI: 5.3-7.6) and with TMZ was 6.7 years (95% CI: 5.7-8.0); HR 0.98 (95% CI: 0.67-1.44). For oligodendroglioma, IDHmt/codeleted (n = 109) median OS with RT was 12.9 years (95% CI: 9.4 - NE) and with TMZ 14.9 years (95% CI: 10.1 - NE); HR 1.01 (95% CI: 0.56-1.81). For a heterogenous group of IDHwt tumors (n = 64), median OS with RT was 2.5 years (95% CI: 1.8-3.3) and with TMZ 4.7 years (95% CI: 2.2-7.2); HR 0.37 (95% CI: 0.18-0.77). CONCLUSIONS Primary treatment with RT or TMZ provided comparable PFS and OS. Choice of primary treatment can be tailored to individual tumor characteristics and patient preference.

DA-R-EPOCH May Mitigate the Adverse Prognostic Implication of the Diagnosis-to-Treatment Interval (DTI) in Large B-Cell Lymphomas

BackgroundShort diagnosis-to-treatment interval (DTI) is associated with high-risk disease and poor survival in diffuse large B-cell lymphoma (DLBCL). There is a paucity of literature on DTI and survival in DLBCL treated with first-line DA-R-EPOCH. We hypothesized that rapid initiation of DA-R-EPOCH in aggressive and high-risk DLBCL mitigates the adverse prognostic implication of short DTI. Patients and MethodsWe retrospectively examined the association of DTI, categorically (short DTI ≤ 14 and long > 14 days) and continuously, with clinical features and survival outcomes in DLBCL treated with first-line DA-R-EPOCH at our institution. ResultsA total 190 patients were analyzed, 21% with high-grade DLBCL subtypes, 56% IPI ≥ 3, and median DTI of 13 days. The short DTI cohort contained more patients with IPI ≥ 3, bulky disease, and elevated LDH. When analyzed categorically and continuously, DTI was not associated with significant differences in PFS or OS. There was significant multivariable interaction between bulky disease, DTI, and PFS (P = .033), with improved PFS in patients with bulky disease in the short DTI cohort. ConclusionWe found that negative prognostic implications of DTI are mitigated in DLBCL patients treated with first-line DA-R-EPOCH, suggesting that urgent initiation of DA-R-EPOCH in high-risk DLBCL, including bulky disease, may improve survival. Our study's shorter DTI compared with DTIs reported in prospective DLBCL trials highlights DTI as a marker of external validity in clinical trial results. Future trials should implement protocols encouraging shorter, realistic DTIs to avoid selection bias against high-risk patients who are unable to delay treatment.

Abstract C054: Clinicogenomic determinants of response to FOLFIRINOX versus gemcitabine plus nab-paclitaxel as first-line systemic therapy for pancreatic cancer

Abstract Background: FOLFIRINOX (FFX) and gemcitabine plus nab-paclitaxel (GA) are two recommended first-line systemic options for pancreatic cancer; however, there is limited evidence to support a particular regimen or provide guidance for treatment selection. We sought to compare outcomes for FFX versus GA across disease stages, and test whether there was an association between clinicogenomic features, treatment response, and survival. Methods: For this retrospective analysis, we utilized AACR’s GENIE PANC v1.2 database, the first large-scale pancreatic cancer dataset that combines genomic data with clinical annotations. The clinicogenomic profiles of patients were stratified and compared by stage: resectable/borderline resectable (R/BR), locally advanced (LA), or metastatic (MET). Patients who received FFX or GA as first-line therapy were compared across stages, with a focus on MET patients. We evaluated OS and PFS as survival outcomes and performed an adjusted analysis using Cox proportional hazards modeling. Treatment responses were further evaluated by change in serum CA 19-9. To test for features associated with treatment response, the genomic profiles of best and worst responders were compared. Results: Of 987 patients with complete genomic data, there were 452 R/BR, 82 LA, and 453 MET. While there was no difference in KRAS status, patients with later-stage disease accumulated greater common co-alterations: CDKN2A (19%, 23%, 35%), SMAD4 (26%, 29%, 30%), TP53 (72%, 73%, 77%), and ARID1A (6%, 6%, 11). Within MET patients, there was no significant difference in PFS between those treated with FFX (n=239) and GA (n=82), but patients treated with FFX had significantly longer OS, even after multivariable adjustment (median 1.14 vs. 0.854 years, p < 0.01; HR: 0.66, 95% CI: 0.49- 0.89, p < 0.01). Despite improved OS in FFX patients, GA patients had a greater reduction in CA 19-9 (median 50.0 vs. 69.0 U/mL). In addition, when comparing the genomic profiles of best/worst responders for MET patients treated with FFX and GA, there was no clear signal that one regimen should be favored over another in a specific context. Exploratory analyses in the R/BR and LA groups indicated no significant survival differences between first-line FFX vs. GA patients, nor in first-line treatment among patients who developed metastases post- diagnosis. Conclusion: Common co-alterations appear to accumulate in later-stage disease, and outcomes in patients undergoing systemic therapy is worse generally in patients with more complex genomic profiles. However, we did not observe any specific genomic features suggestive of a particular response to FFX vs. GA. Of note, we found that Met GA patients had a larger magnitude in CA 19-9 response, even though Met FFX was associated with improved OS. This provokes important questions regarding how biochemical response should be gauged in patients treated with these regimens. Citation Format: Kunling Tong, Elishama Kanu, Ethan Agritelley, Jiayin Bao, Peter J Allen, Daniel P Nussbaum. Clinicogenomic determinants of response to FOLFIRINOX versus gemcitabine plus nab-paclitaxel as first-line systemic therapy for pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr C054.

VCd versus VRd in Newly Diagnosed Multiple Myeloma: Matched Real-World Analysis from the Balkan Myeloma Study Group (BMSG)

BackgroundBortezomib, dexamethasone and cyclophosphamide (VCd) remains a popular regimen, due to its activity and low toxicity, while bortezomib, lenalidomide and dexamethasone (VRd) is widely used in US and Europe; both are combined with anti-CD38 monoclonal antibodies but VCd and VRd have not been compared directly in adequately powered prospective trials. AimWe compared the outcomes of 1216 patients treated with VCd (N = 690) or VRd (N = 526) in a real-world setting. ResultsPatients treated with VCd had more often severe renal dysfunction, ISS-3 disease, hypercalcemia, elevated LDH, anemia, thrombocytopenia, poor performance while VRd-treated were older and received less often autologous transplant but more frequently maintenance but the duration of induction was similar. VRd was associated with substantially higher overall response and CR/VGPR rates to induction(P < .001) and improved PFS and OS in univariate analysis, especially among patients with standard risk disease, without renal dysfunction and in the elderly; however, in multivariate analysis there was no significant difference in either PFS or OS. In patients strictly matched 1:1 for major prognostic variables (188 in each group, total N = 376), the superiority of VRd in terms of responses rates and depth of response was confirmed, but without significant PFS or OS difference. ConclusionVRd is a more active induction regimen than VCd, although use of maintenance with lenalidomide may dilute the PFS or OS benefit. VCd induction remains an option in special circumstances. With the implementation of monoclonal antibodies, VCd backbone can be considered for patients without access to or who do not tolerate VRd.

Delayed addition of PD-1/PD-L1 inhibitors into chemotherapy on the outcomes for patients with extensive-stage small cell lung cancer: A propensity score-matched study.

208 Background: Immunotherapy in combination with chemotherapy has become the first-line treatment for extensive-stage small cell lung cancer (ES-SCLC). However, some patients failed to undergo simultaneous immunotherapy at the time of initial chemotherapy, and whether this will have an impact on the efficacy of immunochemotherapy has not been fully explored. Methods: Between January 2020 and December 2022, the study included 416 patients diagnosed with ES-SCLC and receiving first-line immunotherapy, divided into two groups: delayed-IO (administering PD-1/PD-L1 inhibitors at 2-4 Cycles of chemotherapy) and early-IO (administering PD-1/PD-L1 inhibitors concurrent with first-cycle chemotherapy). Propensity score matching (PSM, 1:1) was performed to balance the baseline characteristics of the two groups. The primary endpoints were OS and PFS. Calculations were performed using the Kaplan-Meier method and comparisons were made using the log-rank test. Results: Mainly due to the fact that PD-L1/PD-1 inhibitors were not included in the medical insurance, which was difficult for patients to afford and the poor physical condition of some patients, taking into account the safety of the patients themselves, 72 patients in the delayed-IO group (2 cycles of chemotherapy: 41; 3 cycles: 16; 4 cycles: 15), and 344patients were included in the early-IO group. The median OS and PFS were 24.00 months and 8.75 months in the delayed-IO group, and those were 18.59 months and 7.57 months in the early-IO group, respectively, before PSM. There was no significant difference in OS and PFS between the two groups (HR 0.72; P = 0.054 and HR 0.86; P = 0.281, respectively). After PSM, there were 72 patients in each of the two groups. The median OS in the delayed-IO group and the early-IO group was 24.00 months and 18.79 months, respectively (HR 0.60, 95% CI 0.38-0.97; P = 0.037). Median PFS was 8.75 and 6.49 months in the two groups, respectively (HR 0.69, 95% CI 0.48-0.99; P = 0.044). There was a statistically significant difference between the two groups. The overall adverse event profile was comparable between the two groups. Conclusions: Our findings suggest that administering PD-1/PD-L1 inhibitors at 2-4 Cycles of chemotherapy was superior to administering PD-1/PD-L1 inhibitors concurrent with first-cycle chemotherapy in patients with ES-SCLC, while the safety profile of both was similar.

Baseline 18F-FDG PET/CT may contribute to the determination of initial treatment strategy for newly diagnosed follicular lymphoma

Background“Watch-and-wait” approach is an important management option in asymptomatic follicular lymphoma (FL) patients with low tumor burden. Since most FL lesions are FDG-avid, we wonder if 18F-FDG PET/CT at baseline can help to better choose the patients who can benefit from early chemotherapy. This study aimed to investigate the prognostic value of baseline 18F-FDG PET/CT in newly diagnosed FL patients treated with either watch-and-wait approach or chemotherapy. ResultsPatients received chemotherapy as initial treatment had higher Ann Arbor stage, higher incidence of extranodal involvement and bulky disease, more involved lymph nodes larger than 3 cm, and higher SUVmax, MTV, and TLG than those managed with watch-and-wait approach (p < 0.05). The median PFS and TTNT in patients received chemotherapy and under watch-and-wait did not show significant difference, however patients with MTV<111.66 mL or TLG<141.50 SUVbw*mL had significantly longer PFS and TTNT than those patients with MTV≥111.66 mL or TLG≥141.50 SUVbw*mL (p < 0.05). Further analysis revealed that for patients with TLG≥141.50 SUVbw*mL or MTV≥111.66 mL, those who received chemotherapy as initial treatment had a significantly longer PFS and TTNT than those managed with initial watch-and-wait approach (p < 0.05). However, for patients with MTV<111.66 mL or TLG<141.50 SUVbw*mL in baseline PET/CT, there was no significant difference in PFS or TTNT between patients who received chemotherapy and those under watch-and-wait. ConclusionBaseline 18F-FDG PET/CT may provide prognostic value and help to improve the decision-making of initial treatment plans for newly diagnosed FL patients.

Prospective Study to Assess the Clinicopathological and Prognostic Value of BRAF V600E Mutation in Metastatic Colorectal Cancer

Abstract Background BRAF is a protein kinase downstream of RAS in the RAS-RAF-MEK- ERK kinase pathway. The majority (&amp;gt;95%) of BRAF mutations in metastatic colorectal cancer (mCRC) is the BRAFV600E mutation, which is considered an important negative prognostic marker and is associated with resistance to standard chemotherapies in mCRC patients. Objectives This study aimed to investigate the BRAF mutation in patients with mCRC and its association with clinicopathological factors and survival outcomes. Patients and Methods The included specimens were analysed for BRAFV600E mutation by immunohistochemistry (IHC) from confirmed CRC patients with radiological or pathological evidence of metastasis. Results The BRAF mutation was positive in 9.1% of patients. Synchronous metastasis was observed in patients with BRAF mutation with statistical significance (P = 0.033). With regard to treatment, there was no statistically significant difference in patients with BRAF mutations who received targeted chemotherapy as first-line therapy also there was no statistically significant difference in median PFS of patients with BRAF mutation (p = 0.789) and also in median OS (p = 0.343). Conclusion Although the BRAF mutation is a relatively rare finding in mCRC, it is characterized by a critical negative impact on treatment outcome. Given this poor outcome, optimization of therapy is an important goal.

Overexpression of Estrogen Receptor Beta and Its Prognostic Significance among Malignant Pleural Mesothelioma Patients

Abstract Background The expression of estrogen receptor beta (ER beta) and its correlation with the prognosis of malignant mesothelioma remains controversial. This study aimed at studying ER beta expression in tumour cells in patients with mesothelioma and its association with clinicopathological factors and survival outcomes. Material and Methods A prospective study to evaluate prognostic significance of ER beta overexpression by immunohistochemistry (IHC) on paraffin blocks among malignant mesothelioma patients at Ain Shams university hospital and correlate their overexpression with the patients' follow up clinical data, OS, and PFS. Results Forty-two mesothelioma cases were enrolled and followed up, High ER beta expression (modified Allred score 7-9) was reported in 9.5% of the patients (4 cases), moderate expression (modified Allred score 4-6) was reported in 28.6% of the patients(12 cases), weak and negative expression ( modified Allred score 0-3) was reported in 61% of the patients(26 cases), percent of ER beta positive cases was 69% of the total patients, there was no statistical difference as regard age (p value:0.8), sex(p value:0.4), stage (p-value: 0.71), ECOG (p-value :0.84), histological subtype(p value:0.17) and response to first-line treatment (p value:0.5) across the 3 groups of patients (high, moderate, weak and negative ER beta on tumour cells).there was no statistically significant difference in OS and PFS for ER beta overexpression. Conclusion ER beta overexpression was not associated with improved OS or PFS in mesothelioma patients, larger sample size would be recommended for more solid conclusions.

Concomitant Administration of VEGFR Tyrosine Kinase and Proton Pump Inhibitors May Impair Clinical Outcome of Patients With Metastatic Renal Cancer

IntroductionThe administration of proton pump inhibitors (PPIs) is a common practice to reduce gastro-esophageal adverse events associated with drug treatments but may impair absorption and exposure to oncology drugs. This study investigated the effect of concomitant administration of PPIs and pazopanib, sunitinib and cabozantinib on survival of patients with metastatic clear cell renal carcinoma (mRCC). Patients and MethodsTotal 451 patients receiving pazopanib, sunitinib and cabozantinib as first line treatment were enrolled in this retrospective study. Patients were defined as “no concomitant PPIs (PPI−)” if no PPIs were administered during TKIs, and as “concomitant PPIs (PPI+)” if the administration of PPIs was at least 75% of the time during which TKIs were given. ResultsEighty patients administered pazopanib were PPI− and 86 PPI+; no difference in PFS was observed (10.7 vs. 11.9 months, P = .79). If patients were stratified as short (n = 89) and long (n = 77) responders, there was a significant difference in terms of PFS in PPI+ (n = 47) versus PPI− (n = 30) in long responders, being 24.7 versus 38 months (P = .04), respectively. In the sunitinib cohort, no significant difference of PFS in PPI+ (n = 102) versus PPI− (n = 131) was found, being 11.3 versus 18.1 months, respectively (P=0.15). In the cabozantinib cohort, there was a statistically significant difference in PFS of PPI+ versus PPI− (6 months vs. not reached, P = .04). No correlation with adverse events was found. ConclusionsThis study demonstrates an association between PPIs and impaired PFS in mRCC patients given pazopanib and cabozantinib and recommends caution on their concomitant use.

Comparison of the efficacy and safety of domestically produced tislelizumab, camrelizumab, and imported pembrolizumab in the treatment of advanced NSCLC: a real-world retrospective study.

Since the imported PD-1 inhibitor pembrolizumab was listed in China in 2018, China has opened up the era of immunotherapy for malignant tumors, with several domestically produced PD-1 inhibitors coming onto the market one after another. To find out whether there are differences in the efficacy and safety of domestic and imported PD-1 inhibitors in patients with advanced non-small cell lung cancer, we conducted this retrospective study in two tertiary hospitals in China. Patients with advanced NSCLC treated with tislelizumab or camrelizumab or pembrolizumab who met the inclusion criteria were screened through the electronic medical record system. A total of 259 patients were screened, but due to the unbalanced baseline, we performed propensity score matching and finally included 149 patients in three groups: pembrolizumab (n = 38), tislelizumab (n = 38), and camrelizumab (n = 73), which had very balanced baseline characteristics in each group after propensity score matching treatment. The results showed that the median progression-free period was 11.3m vs 10.1m vs 8.9m; p = 0.754; and the objective response rate was 63.2% vs 50% vs 57.5%; P = 0.510 for pembrolizumab, tislelizumab, and carrelizumab, respectively. There was no significant difference in median PFS between PD-L1 expression subgroups. In terms of safety, only skin toxicity of any grade of carrelizumab was higher than that of the other two groups (p = 0.034), and the incidence of grade ≥ 3 adverse reactions was not statistically significant among the three groups. In this real-world study, the efficacy and safety of the domestically produced tislelizumab, camrelizumab, and the imported pembrolizumab were comparable.

EPID-09. CONGENITAL CENTRAL NERVOUS SYSTEM NEOPLASMS: A RETROSPECTIVE REVIEW FROM THEMARGARET HACKETT FAMILY PROGRAM CONSORTIUM

Abstract INTRODUCTION Congenital intracranial neoplasms are a heterogeneous group of lesions that account for &amp;lt;2% of pediatric CNS tumors. Current understanding of histopathologic and survival outcomes in this population is limited. METHODS Pediatric patients (&amp;lt;3-years) with congenital neoplasms were retrospectively evaluated across five institutions. Demographic, prenatal care, clinical presentation, histopathologic characteristics, operative and adjuvant therapies, and survival outcomes were collected. RESULTS 323 patients met inclusion. The mean age at diagnosis was 1.5-years. Six patients were conceived through IVF. Eleven families reported abnormal prenatal ultrasounds, although only six were diagnosed prenatally. The most common histopathologies included low-grade astrocytoma (30.6%), ependymoma (15.8%), ATRT (11.5%), medulloblastoma (8.0%), and high-grade astrocytoma (2.8%). 48.9% of patients had low-grade neoplasms, and a third of patients (33.1%) had high-grade tumors. Patients commonly presented with hydrocephalus (59.1%), emesis (34.7%), ocular abnormalities (20.4%), macrocrania (18.0%), lethargy (14.6%), developmental delays (12.7%), and irritability (11.8%). All patients received surgical resection: 55.4% received gross-total (GTR) and 20.4% received subtotal resection. Concurrent treatment with adjuvant therapies occurred in a subset of patients, with 52.9% of patients receiving chemotherapy, 27.2% undergoing radiation, and 6.2% participating in a clinical trial. Patients with low-grade tumors had a rate of 88% progression-free (PFS) at 1-year, 74% PFS at 3-years, and 64% PFS at 5-years post-operative. Patients with high-grade neoplasms had worse PFS, with estimates at 59%, 40%, and 37% at 1-, 3-, and 5-years, respectively. There was statistically significant differences in PFS between patients with high- and low-grade neoplasms (p&amp;lt;0.0001). CONCLUSIONS This series consisted of very young pediatric patients across five participating institutions with diverse histopathologies that vary in frequency relative to the entire pediatric population. Lesions were rarely detected prenatally, despite their young age at diagnosis. GTR occurred in half of patients and subsequent management with adjuvant therapies was common in both sub-totally resected low-grade lesions and high-grade tumors.

The efficacy and safety of trastuzumab biosimilar HLX02 compared with reference trastuzumab plus pertuzumab in combination with chemotherapy as the first-line treatment for HER2 positive metastatic breast cancer: A real-world study in China.

e13016 Background: Dual-targeted anti-HER2 therapy with trastuzumab (H) and pertuzumab (P) significantly improves outcomes in HER2-positive breast cancer and has become the first-line standard treatment for patients with advanced HER2-positive breast cancer in China in 2019 based on the results of the CLEOPATRA and PUFFIN study. HLX02 (Zercepac) was the first trastuzumab biosimilar manufactured in China. Here, we present the first real-world comparison of HLX02 versus reference trastuzumab (RTZ) and pertuzumab with chemotherapy as the first-line treatment for HER2-positive metastatic China.Between January 2019 and August 2023, 121 patients with HER2-positive MBC patients were enrolled at Beijing Cancer Hospital in China. These patients received HLX02 or RTZ in combination with pertuzumab and various chemotherapies as first-line treatment. We retrospectively analyzed survival outcomes, efficacy, and adverse events. Methods: Between January 2019 and August 2023, 121 patients with HER2-positive MBC patients were enrolled at Beijing Cancer Hospital in China. These patients received HLX02 or RTZ in combination with pertuzumab and various chemotherapies as first-line treatment. We retrospectively analyzed survival outcomes, efficacy, and adverse events. Results: Both groups, 68 received RTZ and 53 received HLX02, showed similar characteristics of age, disease status (de novo or recurrent), metastatic sites (visceral or non-visceral), and treatment history. A total of 118 (97.5%) received trastuzumab plus pertuzumab combined with chemotherapy as the first-line palliative therapy, with a median number of 6 cycles in each group. Taxanes were the most commonly used chemotherapy regimen in both groups (91.2 vs. 92.5%), including nab-paclitaxel (44.1 vs. 45.3%), docetaxel (41.2 vs. 17.0%), paclitaxel (5.9 vs. 30.2%). With a median follow-up of 15.0 months (range 1.0 - 58.0), the results showed no significant difference in PFS between the RTZ and HLX02 arms (median PFS: 22.0 vs. 19.0 months, p=0.900). Additionally, the efficacy outcomes, including objective response rate (ORR), disease control rate (DCR), and safety profiles did not show significant differences between the two groups. Among 121 patients, 20 patients (16.5%) experienced CNS progression. For these patients, the median time from the first-line therapy to the CNS progression was 15.0 months (95% CI 12.8 - 17.2). Conclusions: The real-world data suggest similar efficacy and safety of HLX02 and RTZ plus pertuzumab with different chemotherapy regimens as the first-line treatment for patients with HER2-positive advanced breast cancer patients in China. Overall, the PFS was consistent with the CLEOPATRA trial in both groups, and there was no new safety signal.

Impact of immune-related adverse events (irAE) onset on disease response and survival in patients (pts) with head-neck cancer treated with immune check point inhibitors (ICI).

6028 Background: ICI or combination chemo-immunotherapy are the mainstay of therapy for metastatic head-neck squamous cell carcinoma (mHNSCC) due to durable responses in certain pts. irAEs have emerged as a new challenge in the management of these pts. Some studies suggest a positive correlation between irAE onset and ICI efficacy in other cancers, however, whether such an association exists in HNSCC remains incompletely explored. Methods: We performed a retrospective, single-center cohort study of pts ≥ 18 years of age, with histologically confirmed mHNSCC who received ≥ 1 dose of ICIs at the University of Virginia Comprehensive Cancer Center, VA, USA between 2013-2022. Demographics, disease and treatment characteristics, and clinical outcomes related to irAEs and ICI re-challenge were analyzed. IrAEs were graded using CTCAE v4.0 criteria by chart review. Independent sample t-tests and chi-square analyses were used for univariate comparisons. Median PFS and OS from ICI therapy initiation were estimated using Kaplan-Meier methodology and censored at date of last follow up. P-values &lt;0.05 were considered statistically significant. Results: Of 1979 pts who received ICI, 110 had mHNSCC (72.7% male; 84.5% White) with a median age of 62.4 years. ICI type included pembrolizumab or nivolumab in 109 pts, and nivolumab/ipilimumab in one pt. 53 (48%) pts experienced any grade irAE and 12 pts (11%) experienced &gt;1 irAE. The most common irAEs were hypothyroidism (30.4%), dermatitis (14.3%), and hepatitis (10.7%). CTCAE ≥G3 irAEs were seen in 22.6% pts (n=12). These included hepatitis (n=3), colitis (n=3), hypothyroidism (n=1), arthritis (n=1), pneumonitis (n=1), adrenal insufficiency (n=1), vasculitis (n=1), and cardiomyopathy (n=1). Men (62% vs 37%, p= 0.015) and pts with prior radiation therapy (83% vs 17%, p=0.047) were more likely to experience irAEs. Treatment interruption/discontinuation occurred in 43% pts with irAEs. Topical/supportive therapy was required in 52.8%, and 35.8% required systemic corticosteroids, with more than half experiencing complete irAE resolution. A statistically significant association was observed between irAE onset and objective response rate (68% vs 39%, p= 0.009). 12 pts underwent ICI re-challenge, resulting in partial response in 3 (25%), stable disease in 4 (33.3%) and progressive disease in 3 (25%) pts. There was no statistically significant difference in PFS (4.9 vs 9.7 months, p = 0.731) or OS (30.5 vs 21 months, p = 0.159) in irAE vs non-irAE groups, respectively. Conclusions: irAEs onset was associated with improved best response to ICI therapy in mHNSCC. Although OS was numerically superior in the irAE group, it did not meet statistical significance. ICI re-challenge is feasible in select pts, however further studies are needed to evaluate long term benefit of ICI re-challenge.

The Reduction of CD4+ T Lymphocytes after the Treatment of Follicular Lymphoma with the Bendamustine Containing Regimen May Predict the Occurrence of Infection and Efficacy

To investigate the effectiveness, safety, and related prognostic factors of the treatment of follicular lymphoma (FL) with a regimen containing Bendamustine. The clinical data of 129 FL patients who were treated with Bendamustine containing regimen were collected from January 1,2020 to October 30,2022 in the Hematology Department of Lianyungang Second People's Hospital and Jiangsu Provincial People's Hospital. The patients were divided into three groups: Bendamustine plus Rituximab (BR), Bendamustine plus Obinutuzumab (GB), Rituximab + Cyclophosphamide + Epirubicin / Doxorubicin + Vindesine + Prednisone (R-CHOP). The efficacy, safety and related prognostic factors of the treatment of FL with a regimen based on Bendamustine were retrospectively analyzed. The ORR was 98% for the BR group, 94% for the GB group, and 72.3% for the R-CHOP group, while the CR rate was 61.2%,70% and 40.4%, respectively. The ORR and CR rates of the R-CHOP group were statistically different from those of the BR group and GB group (P < 0.05). The 3-year PFS rate of the BR group, GB group, and R-CHOP group was 89.6%, 90.9%, 48.9%, respectively. There was a statistically significant difference in 3-year PFS between the R-CHOP group, BR group, and GB group (P < 0.05), while there was no statistically significant difference in 3-year OS（P ＞0.05）. Hematological adverse reactions were mainly bone marrow suppression. Lymphocytes and CD4+T lymphocytes decreased to the lowest level about 6 months after treatment, and the incidence of lymphopenia in BR group and GB group was higher than that in R-CHOP group, with a statistical difference (P < 0.05). The higher incidence of non-Hematological adverse reactions were pulmonary infection, EB virus infection, hepatitis B virus reactivation, and gastrointestinal reactions without statistical difference in 3 groups (P >0.05), and were all controllable. The Receiver operating characteristic of CD4+T lymphocyte count showed that AUC of BR group was 0.802, and the critical value was 258/uL; AUC of GB group was 0.754 with a critical value of 322/uL. The treatment of FL with the Bendamustine containing regimen has good efficacy and controllable adverse reactions, but lymphocytopenia was significant after treatment, and the curative efficacy in combination with various CD20 monoclonal antibodies was different. The lowest CD4+T lymphocyte count can be used as a predictive factor for the occurrence of infection and efficacy of the Bendamustine containing regimen for FL.

Outcomes of patients with peritoneal carcinomatosis treated with HIPEC and chemotherapy or HIPEC alone: A single center community experience.

e15578 Background: Peritoneal carcinomatosis is a common presentation of intraperitoneal malignancies. The optimal management of peritoneal carcinomatosis is currently unknown but can contain a combination of HIPEC and chemotherapy. Optimal timing and order of these interventions is controversial. HIPEC surgery alone can provide a cure rate of approximately 16% with macroscopically complete resection. The PRODIGE 7 trial demonstrated no difference in overall survival between HIPEC plus cytoreduction versus cytoreduction alone with six months of systemic chemotherapy. Which patients should receive HIPEC, chemotherapy and HIPEC or chemotherapy alone remains unknown. Methods: This is a single center, retrospective chart review assessing all patients age 18 and above who received HIPEC surgery with and without the administration of chemotherapy at Ascension Saint John Hospital. Results: We found that there was no significant difference in overall survival and progression free survival between the HIPEC and HIPEC with chemotherapy group with a OS of 57.2 months and 52.5 months; and PFS of 33.6 and 34.4 months respectively. We found that patients with a PCI score between 0 and 13, overall survival favored the HIPEC alone group versus the HIPEC with chemotherapy with a p value of 0.043. There was no difference in progression free survival and overall survival in all other groups when stratified by PCI. When stratified by disease subtype, we no differences between PFS and OS for both appendiceal and colon cancer. Conclusions: The primary objective of this study was to investigate the difference in overall survival and progression free survival among patients with peritoneal carcinomatosis when treated with either HIPEC with systemic chemotherapy versus HIPEC alone. This analysis among 100 patients showed no statistically significant differences in OS or PFS for patients receiving a combination of HIPEC with systemic chemotherapy versus HIPEC alone. The only exception to this was with respect to OS in patients with a PCI score between 0-13. In this group, 0 patients in the HIPEC along group experienced disease progression where 5 progressed in the HIPEC and chemotherapy group. Our data suggests that HIPEC alone may be a reasonable treatment approach for patients with a low PCI score. Important conclusions can be drawn from the data when compared to historical trials. The PROTEGE 7 study found that the median overall survival was approximately 41.7 months for the HIPEC and cytoreductive surgery group and 41.2 months versus cytoreductive surgery alone. The overall survival for the HIPEC alone group was 57.2 months and 52.5 months for the HIPEC plus chemotherapy group. This data suggests that the combination of HIPEC and chemotherapy is a reasonable approach to patients with peritoneal carcinomatosis.

Real-world study of anlotinib monotherapy and combination therapy for unresectable hepatocellular carcinoma.

e16146 Background: Unresectable hepatocellular carcinoma (uHCC) is an aggressive tumor with poor prognosis. Anlotinib is a novel small-molecule tyrosine kinase inhibitor (TKI) that selectively targets VEGFR, FGFR, PDGFR, and c-kit receptors. Clinical trials have confirmed the efficacy and safety of anlotinib monotherapy or anlotinib-based combination therapy for uHCC. However, many patients in clinical practice fail to meet the criteria for these trials. Therefore, this study aimed to investigate the efficacy and safety of anlotinib, as monotherapy or in combination therapy, for uHCC in clinical practice in China. Methods: This multicenter, real-world study enrolled patients with uHCC who had received anlotinib-based therapy, and completed at least one post-treatment efficacy assessment between July 2020 to February 2023. Patients who did not undergo imaging after one cycle of treatment, were lost to follow-up before completing one cycle of treatment, or required systemic chemotherapy or radiotherapy for the primary lesion were excluded from the study. The efficacy assessments were performed based on the RECIST version 1.1. OS, PFS, TTP, DCR and ORR for patients with anlotinib monotherapy (n = 12) and anlotinib-based combination therapy (n = 60) were evaluated. The main statistical analysis was conducted using the Kaplan–Meier method and log-rank test. Subgroup comparisons were performed based on different combinations of anlotinib therapy and the number of treatment lines in patients with uHCC. Occurrence of adverse events (AEs) to evaluate the safety profiles of anlotinib monotherapy or anlotinib-based combination therapy was collected. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire HCC-18 (EORTC QLQ-HCC18) was used to evaluate health-related quality of life (HRQOL). Results: For the anlotinib monotherapy group, the OS, PFS, TTP, DCR and ORR were 14.2 months, 6.9 months, 7.9 months, 16.7%, and 50.0%, respectively. For the anlotinib-based combination therapy group, these values were 15.8 months, 8.6 months, 10.2 months, 25.0%, and 65.0%, respectively. There was no significant difference in OS, PFS, and TTP between the two groups. PFS were significantly decreased in the non-first-line treatment group compared to the first-line treatment group. The incidence of drug-related AEs of any grade was 93.1%, with the most common grade ≥3 treatment-related AEs being lymphopenia and elevated transaminases. The time to deterioration was 14.0 months (95%CI: 8.3–19.8) and 12.2 months (95%CI: 9.8–14.7) in the monotherapy and combination therapy groups. Conclusions: Anlotinib demonstrated satisfactory efficacy and safety as a single agent and in combination with other therapies in the treatment of uHCC, with potential benefit on health-related quality of life.

Effect of time-of-day nivolumab and stereotactic body radiotherapy in metastatic head and neck squamous cell carcinoma: A secondary analysis of a prospective randomized trial.

Prior work documented circadian rhythm impacts on efficacy and toxicity of cancer therapies. Secondary analysis of prospective, phase II trial of metastatic HNSCC randomized to nivolumab+/-SBRT. Used cutoffs of 1100 and 1630. Timing classified by first infusion or majority of SBRT (e.g., PM SBRT defined by two or three fractions after 1630). Of 62 patients, there was no significant difference in median PFS between AM nivolumab (n = 7, 175 days), PM nivolumab (n = 21, 58 days), or Mid-Day nivolumab (n = 34, 67 days; p = 0.8). There was no significant difference in median PFS with AM SBRT (n = 4, 78 days), PM SBRT (n = 13, 111 days), or Mid-Day SBRT (n = 15, 63 days; p = 0.8). There was no significant difference in Grade 3-4 toxicity or ORR. Sensitivity analyses with other timepoints were negative. Further work may elucidate circadian impacts on select patients, tumors, and therapies; however, we found no significant effect in this study.

Therapeutic Patterns and Clinical Outcomes in Limited Disease Small Cell Lung Cancer: A Decade of Analysis at a Tertiary Cancer Center.

In this study, we investigated the outcomes and factors influencing treatment efficacy in 93 patients with limited disease small cell lung cancer (LD-SCLC), with a median age of 64 years. We focused on the impact of chemotherapy regimens, prophylactic cranial irradiation (PCI), and patient-related variables. The median follow-up for OS was 17.3 months. We observed a statistically significant difference in PFS between LD-SCLC patients treated with cisplatin and etoposide (EP) and those treated with carboplatin and etoposide (CP) (PFS: EP 13.63 months vs. CP 6.54 months, p < 0.01). Patients treated with EP had better overall survival (OS) than CP-treated patients (OS: EP 26.9 months vs. CP 16.16 months, p < 0.01). Concomitant chemotherapy was associated with improved PFS (p = 0.003) and OS (p = 0.002). Patients receiving PCI showed superior OS (p = 0.05) and a trend towards improved PFS (p = 0.057). Female gender was associated with better OS (p = 0.025). Most patients had an ECOG performance status of 0 (71%). This real-world study underscores the importance of multidisciplinary LD-SCLC management, emphasizing the roles of chemotherapy, radiotherapy, and PCI. These findings inform personalized treatment strategies and emphasize the need for prospective trials to validate these results and optimize LD-SCLC treatment.

Abstract PO2-16-10: Characterising HER2-low status in metastatic breast cancer: a real-world retrospective study of patients at a metropolitan cancer centre in Australia

Abstract Background: Traditionally, breast cancer subtyping has described patients as HER2-negative or HER2-positive, with the latter being those in whom HER2-directed therapies are utilised. A proportion of HER2-negative cancers can be classified as “HER2-low” as they express IHC 1+ or 2+ and are non-amplified on in-situ hybridisation (ISH). Until recently, our widely available HER2-targeted therapies have proven to be ineffective in this subtype. The DESTINY-BREAST04 trial (Modi et al, NEJM 2022) showed progression-free and overall survival efficacy of HER2-directed therapy using the antibody-drug conjugate (ADC) trastuzumab deruxtecan (T-DXd) in HER2-low disease, suggesting a need to identify this population for selected therapy. This study evaluated a real-world population of metastatic breast cancer (MBC) patients treated according to traditional breast cancer subtypes to determine the frequency of HER2-low histology, with a focus on selection of first-line therapy. Methods: This retrospective audit identified patients being treated for MBC at a single tertiary hospital (Austin Health in Melbourne, Australia) over a 3.5 year period. Patients were identified from an electronic database, with a date of last follow-up as August 2022. Medical records were interrogated for clinicopathological information including review of pathology reports for breast cancer subtypes. Traditional breast cancer subtypes were defined as (i) ER positive and HER2-negative (HER2 0 or 1+, or 2+ and non-amplified); (ii) HER2-positive (HER2 3+ and/or amplified) and (iii) TNBC (negative for ER and PgR, and HER2 0 or 1+, or 2+ and non-amplified). Selection and duration of first-line treatment for MBC was also recorded. Results: Between March 2018 and August 2022, 202 MBC patients were identified. Based on traditional subtypes, 126 (62%) were ER positive and HER2-negative, 46 (23%) were HER2-positive, 26 (13%) were TNBC and 4 (2%) were unknown. In the total population, 87 (43%) were classified as having HER2-low disease based on retrospective pathology reports. HER2-low represented 61% of ER positive, HER2-non amplified patients and 45% of TNBC patients. Metastatic specimen data was known for 172 cases and of these, 95 patients (55%) were re-biopsied on metastatic progression. This occurred more commonly with HER2-positive (81%) and ER positive HER2-negative (78%) primaries. The most common change in subtype was loss of ER, which occurred in 7 patients (3%). Changes in HER2 status occurred in 29 (14%) of patients, most commonly as either an increase from 1+ to 2+ or decrease from 1+ to 0. HER2-low status remained consistent for 67% of patients who underwent biopsy on recurrence. For patients with ER positive HER2-negative MBC, first-line combination therapy with a CDK4/6 inhibitor + AI was preferred (51%), followed by single agent endocrine therapy (30%) and chemotherapy (17%). The majority (84%) of HER2-positive patients received first-line dual HER2 therapy (trastuzumab and pertuzumab) with taxane chemotherapy. Half of TNBC patients received upfront chemotherapy, with physician preference being capecitabine (45%). There was no significant difference in PFS between the HER2-low vs. HER2-0 cohorts, for either ER positive or TNBC subtypes. No patients in this series were treated based on HER2-low definition due to no funded access to such therapies at the time. Conclusion: HER2-low has emerged as an identifier for patients who may respond to HER2-directed therapies using ADCs such as T-DXd. However, its clinical significance as a discrete clinical subtype remains uncertain. In this retrospective audit, HER2-low patients were identified in both ER positive and TNBC subtypes. Dynamic changes in HER2 staining occurred infrequently. Further evaluation is needed to address whether HER2-low expression provides any prognostic value and whether prospective reporting of HER2-low status may alter how these new HER2-directed therapies are used in future. Citation Format: Michelle Li, Belinda Yeo. Characterising HER2-low status in metastatic breast cancer: a real-world retrospective study of patients at a metropolitan cancer centre in Australia [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-16-10.

Abstract PO3-16-02: Trastuzumab and taxane chemotherapy in the first-line in MBC patients with a HER2-negative primary tumor and HER2-positive circulating tumor cells: a phase II trial

Abstract Purpose: HER2 overexpressing circulating tumor cells (CTCs) are observed in up to 20% of HER2-negative metastatic breast cancer patients. Since targeted anti-HER2 therapy has drastically increased the outcome of patients with HER2 positive breast cancer, we hypothesized that patients with HER2 overexpressing CTCs might benefit from the addition of trastuzumab to chemotherapy. Methods: In this single-arm, phase II trial, HER2 negative patients with HER2-positive CTCs received trastuzumab as addition to first-line treatment with taxane chemotherapy (trastuzumab group). Patients with detectable CTCs but without HER2 overexpression and that received taxane chemotherapy only, were used as internal control group (taxane monotherapy group). The primary outcome measure was progression-free rate at 6 months (PFR6). The study was powered to reach a PFR6 of 80%; in this case this strategy was considered worth further investigation. In November 2022, the study was terminated early due to slow patient accrual. Results: 63 HER2 negative patients with metastatic disease were screened, of which 8 patients had HER2-positive CTCs and were treated in the first line with trastuzumab in addition a taxane. Patients receiving taxane monotherapy were used as a control group (n = 27). The median number of CTCs was 15 (range 1 – 131) in patients with HER2-positive CTCs, compared to median 5 (range 1-1047) in the control group. PFR6 was 50% in the trastuzumab group and 64% in the taxane monotherapy group, with no significant difference in median PFS (8 versus 9 months, p=0.51). Excluding the patients that had no measurable CTCs, there was a borderline significant difference between median CTC count in the patients that did and that did not have HER2 positive CTCs (p=0.05). We confirmed a significant higher CTC-count in samples that had at least one HER2-postive CTC in an independent patient set (n=233, p&amp;lt; 0.001). Conclusions: Although this study was performed in a limited number of patients, no clinical benefit of trastuzumab was observed. Firstly, we conclude that our strategy was not feasible for clinical implementation due to high numbers needed to screen. And, second, due to the strong correlation between CTC numbers and detected CTC HER2 positivity, the prognostic value of the CTC numbers precludes judgement of any predictive value of the HER2 status of CTCs. Citation Format: Noortje Verschoor, Manouk Bos, Inge de Kruijff, Ngoc M Van, Jaco Kraan, Jan Drooger, Johanna Zuetenhorst, Saskia M Wilting, Stefan Sleijfer, Agnes Jager, John WM Martens. Trastuzumab and taxane chemotherapy in the first-line in MBC patients with a HER2-negative primary tumor and HER2-positive circulating tumor cells: a phase II trial [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-16-02.