Citations

Abstract Low-grade B-cell lymphomas other than follicular and small lymphocytic lymphoma (LGBCL) account for 10% of all B-cell non-Hodgkin lymphomas. Despite improvements in survival outcomes for these patients, little is known about cause of death (COD) in the rituximab era. For a better understanding, we studied 822 newly diagnosed patients with marginal zone, lymphoplasmacytic, and unclassifiable low-grade B-cell lymphoma prospectively enrolled in the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource from 2002 to 2015. COD was assigned based on medical record review using a standard protocol. At a median follow-up of 107 months, 219 (27%) patients had died. The incidence of lymphoma-related deaths when pooling across subtypes was lower than non–lymphoma-related deaths (10-year incidence, 8.0%; 95% confidence interval [CI]: 6.2-10.4 vs 13.6%; 95% CI: 11.2-16.6). The incidence of lymphoma-related deaths varied by subtype, ranging from 3.7% at 10 years in extranodal marginal zone lymphoma to 19.3% in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia. Patients with early progression or retreatment events, defined using event-free survival at 24 months from diagnosis, had significantly higher likelihood of lymphoma-related death compared with patients without early events (10-year estimate: 19.1% vs 5.1%, respectively; P < .001), whereas the rates for non–lymphoma-related death were comparable in patients with or without early events (10-year estimates: 11.0% vs 15.3%, respectively). In conclusion, the most common COD in LGBCLs in the first decade after diagnosis was for causes other than lymphoma. Progression or retreatment within the first 2 years of diagnosis was a strong predictor for risk of lymphoma-related death.

BACKGROUND: The differences between sporadic and multiple endocrine neoplasia type 1 (MEN-1)–associated insulinoma are not well described. Herein, we compared demographics, neoplasm characteristics, presentation, and survival in patients with sporadic vs MEN-1 insulinomas including benign and malignant disease. STUDY DESIGN: A retrospective study identified insulinoma patients. MEN-1 was defined based on genetic testing or clinically in patients with 2 or more primary MEN-1 tumor types. RESULTS: A total of 311 patients were identified: 84% benign and 16% malignant. The incidence of malignancy was similar (18% vs 16%, MEN-1 vs sporadic, p = 0.76). Within malignant patients, the median (interquartile range) age was 33 (25 ,44) years in MEN-1 vs 54 (41, 70) years in sporadic insulinoma (p = 0.04). There was no difference in sex or tumor size between MEN-1 and sporadic malignant insulinoma (p > 0.05). Of the 260 patients with benign insulinoma, 7% had MEN-1 syndrome. MEN-1 patients presented with insulinoma at a younger age: median (interquartile range) age was 38 (24, 49) years vs 52 (43, 65) years (p < 0.01). Resection of benign insulinoma was performed in 78% of the MEN-1 and 94% of the sporadic group (p = 0.03). Resected benign tumors were larger in the MEN-1 group: 2.0 (1.65, 2.45) cm vs 1.5 (1.2, 2.0) cm, respectively (p = 0.03). Concurrent insulinomas were more common in MEN-1 (17% vs 2%; p < 0.01). CONCLUSIONS: MEN-1 patients present with insulinoma at younger age and have larger benign pancreatic lesions at the time of resection compared with sporadic neoplasms. Younger patients and those with multifocal pancreatic neuroendocrine tumor in the setting of endogenous hyperinsulinism should be evaluated for MEN-1.

Abstract Intravascular lymphoma (IVL) is a rare extranodal non‐Hodgkin lymphoma. We performed a retrospective analysis of 55 IVL patients who were treated at our institution 2003–2018. Median age at diagnosis was 68 years, and 64% were males. The most frequent presenting symptoms were skin rash 43% and weight loss 30%. MRI brain on IVL patients with CNS involvement (CNS‐IVL) showed multifocal involvement in 76% (13/17). 89% (17/19) of non‐CNS‐IVL patients with abnormal FDG‐PET had biopsy of an avid lesion resulting in definitive diagnosis. The top diagnostic biopsy site was the bone marrow (45%). 56% had multiorgan involvement. Based on CNS involvement, 36.5% (20/55) had CNS‐IVL and 63.5% (35/55) had non‐CNS‐IVL. CNS‐IVL group consists of clinically isolated CNS involvement (CNS‐only IVL) (22%;12/55) and mixed clinical CNS and peripheral site involvement (M‐IVL) (14.5%; 8/55). Non‐CNS‐IVL group consists of clinically isolated skin involvement (skin‐only IVL) (9%; 5/55) and peripheral IVL with or without skin involvement (P‐IVL); (54.5%; 30/55). Skin involvement was predominantly in the lower extremities. Pathologically, 89% (48/54) were B‐cell IVL. Rituximab + high‐dose methotrexate‐based regimen were used in 75% (12/16) of CNS‐IVL patients and RCHOP in 60% (17/28) of non‐CNS‐IVL patients. Estimated 5‐year progression free survival (PFS) and overall survival (OS) for the entire cohort were 38.6% and 52%, respectively. Skin‐only IVL was associated with excellent survival. Platelet count <150x10 9 /L, age > 60Y, and treatment without Rituximab were poor prognostic factors. Further research is necessary to identify novel therapies.

Abstract Background: DLBCL is the most common non-Hodgkin lymphoma subtype in western countries and is clinically heterogeneous. Gene expression profiling has identified two major biologically distinctive DLBCL subtypes defined by their cell-of-origin (COO): germinal center B-cell (GCB) - characterized by BCL2 rearrangement and C-REL amplification, and activated B-cell (ABC) - characterized by constitutive activation of the NF-kB pathway. We evaluated putative DLBCL risk factors for etiologic heterogeneity as defined by COO. Methods: We used a clinic-based study of newly diagnosed NHL cases and frequency matched controls, enrolled from 2002-2014, with a total of 687 DLBCL cases and 2253 controls for this analysis. Using formalin-fixed, paraffin-embedded tumor tissue, we determined COO by either digital expression profiling (NanoString; classified as GCB, ABC, undetermined) or clinically using the Hans algorithm (immunohistochemical markers; classified as GCB, non-GCB, undetermined). Integrating these two sources of COO data, there were 271 GCB, 170 non-GCB, and 246 undetermined/missing (mainly due to lack of tissue) cases. Risk factor data were collected from self-administered questionnaires and included family history of hematologic malignancy; history of atopy, allergy, asthma, eczema, or autoimmune disease; blood transfusion; vaccination history; regular low-dose aspirin use; body mass index (BMI) 2 years prior diagnosis/enrollment; smoking history; alcohol consumption (never/current/former); leisure-time physical activity; and recreational sun exposure. Polytomous logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals for COO subtypes, adjusted for age, sex and residence. Results: The median age of cases was 64 years with 55% male; the median age of controls was 64 years and 53% male. The association with BMI (30+ vs. 18.5-24.9 kg/m2) was stronger for non-GCB (OR=2.21; 1.40-3.49) than for GCB (OR=1.70; 1.21-2.40) DLBCL (P-heterogeneity 0.02), while a family history of hematologic malignancy was associated with non-GCB (OR=2.27; 1.47-3.50) but not GCB (OR=1.30; 0.86-1.96) DLBCL, although the P-heterogeneity was not significant (P=0.13). For GCB, there was an inverse association with former (vs. never) alcohol use for GCB (OR=0.57; 0.39-0.83) but not for non-GCB (OR=0.98; 0.61-1.57) DLBCL (P-heterogeneity 0.007), and an inverse association with regular use of low-dose aspirin for GCB (OR=0.64; 0.47-0.87) but not for non-GCB (OR=0.88; 0.61-1.25) DLBCL (P-heterogeneity 0.05). No other risk factors evaluated showed important heterogeneity by COO. Conclusions: These initial results suggest most DLBCL risk factors do not show etiologic heterogeneity by DLBCL COO, although associations with BMI and family history with non-GCB DLBCL and alcohol and low-dose aspirin use with GCB DLBCL warrant follow-up. Citation Format: Geffen Kleinstern, Dennis P. Robinson, Lisa M. Rimsza, Melissa C. Larson, Rebecca L. King, Grzegorz S. Nowakowski, Carrie A. Thompson, Stephen M. Ansell, Matthew J. Maurer, Andrew L. Feldman, Susan L. Slager, Anne J. Novak, Thomas M. Habermann, James R. Cerhan. Evaluation of etiologic heterogeneity for risk of diffuse large B-cell lymphoma (DLBCL) subtype defined by cell-of-origin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 741.

e19562 Background: Considerable healthcare resource utilization and financial burden have been associated with the treatment of Waldenstrom Macroglobulinemia (WM); however, the impact of health insurance status on patient outcomes has not been explored. We aimed to assess the insurance-based outcome relationship in WM using the National Cancer Database (NCDB). Methods: We analyzed patient-level data obtained from the NCDB, a database representing more than 70% of newly diagnosed cancer cases nationwide. All newly diagnosed WM cases (n = 8540) between 2004 to 2017 were identified. Only patients who underwent treatment were included. Insurance status was recorded by assessing the primary payer at the time of diagnosis. Due to Medicare eligibility criteria, age-based (< 65 and ≥65 years) stratified analysis was conducted. Cox proportional hazards model was utilized to analyze survival. Time-to-event analysis was conducted based on date-of-diagnosis using the Kaplan-Meier method and log-rank test. Results: Analysis was conducted on 3878 patients after meeting inclusion criteria, with a median follow-up time of 54.6 months. Among patients < 65 years (n = 1249; median age: 58 years; male: 62.4%), those with non-private insurance had inferior survival on multivariate analysis (Table) after adjusting for patient demographics, comorbidities, income, education, treatment center characteristics, and treatment start time. Significant overall survival (OS) differences were seen in those < 65 years (log-rank p < 0.001), with 5-year OS highest among patients with private insurance 91.2%, compared to Medicaid 79.8%, uninsured 77.4%, and Medicare 70.2%. In patients < 65 years, compared to private insurance, uninsured patients were more likely to be of Black race, reside in lower income areas, and be treated at non-academic centers (all p < 0.05). Both Medicaid and Medicare patients < 65 years were more likely to have a higher Charlson-Deyo comorbidity index (> 1) and live in areas of lower educational attainment and household income compared to private insurance (all p < 0.05). In patients ≥65 years (n = 2629; median age: 75 years; 60.6% males), no insurance-based OS (log-rank p = 0.096) differences were seen. Conclusions: Based on our study, significant insurance-based disparities exist in WM, where patients < 65 years old who are uninsured, or non-privately insured are at a higher risk of mortality. While the root cause of these differences is not fully elucidated, efforts should focus on ensuring that all patients have equal access to care regardless of primary payer status.[Table: see text]

e19532 Background: The traditional approach to the treatment of early-stage classical Hodgkin lymphoma (cHL) has been combined modality therapy (CMT) with both chemotherapy and radiotherapy (RT). CMT has shown improved disease control, but RT can lead to long-term adverse effects, including secondary malignancies and cardiac toxicity. Multiple clinical trials have assessed treatment de-escalation strategies to chemotherapy-alone regimens, but results are conflicting. We aimed to assess the real-world implications of these trials by comparing patient outcomes based upon treatment with CMT or chemotherapy-alone. Furthermore, we proposed to assess differences in treatment outcomes stratified by disease bulk, favorable/unfavorable disease, and PET2 response. Methods: We conducted a retrospective, multi-center cohort study of consecutive adult patients with early-stage (stage IA-IIB) cHL treated between January 2010-December 2020. Baseline characteristics, treatment modality, and outcomes were abstracted by chart review. Available PET2 scans (n=110) were independently reviewed by a blinded nuclear radiologist. Deauville score (DS) ≥4 was characterized as positive (+), and DS≤3 negative (-). All analysis was conducted using intention-to-treat principles based upon the initial treatment plan (CMT or chemotherapy-alone). Results: In 125 patients [58% male, median age 34 (range, 18-78)] with early-stage cHL, CMT was intended in 63 (50%) patients, with chemotherapy-alone in 62 (50%). Bulky disease was observed in 43 (34%), unfavorable disease in 81 (65%), and 15 (14%) were found to be PET2+. With median follow-up of 59.8 months (95%CI, 48.6 to 71.0), 5 (4%) deaths occurred, and 17 (14%) patients had relapsed/refractory disease. No significant differences in overall survival (OS) were seen based upon treatment intention. However, there was substantially reduced progression-free survival (PFS) (Table) with chemotherapy-alone in the whole cohort, and also in those with bulky, unfavorable, and PET2+ disease. No significant PFS differences were seen based upon treatment intention for patients with non-bulky, favorable, or PET2- disease. Conclusions: Based on our real-world experience, CMT appears particularly beneficial for patients with bulky disease, unfavorable prognostic factors, and PET2+ disease. However, while recent trials showed a benefit of CMT in non-bulky, favorable and PET2- patients, chemotherapy-alone may be comparable for these patients in actual clinical practice.[Table: see text]

7573 Background: While most patients (pts) with follicular lymphoma (FL) usually have favorable outcomes, those with refractory disease after first-line anti-CD20 based immunochemotherapy (IC), or progression within 24 months of diagnosis (POD24) have higher risk of premature death. There are no standard approaches for treating this vulnerable group and studies testing novel agents are ongoing in this setting. We sought to investigate clinical practice treatment choices and efficacy for pts with POD24 that align with eligibility criteria for the randomized SWOG1608 which compares IC with novel agents in this population. Methods: This was a multicenter observational cohort study from the LEO Consortium. Eligible pts had grade 1-3a FL diagnosed between 1/1/2002 and 2/1/2019, and initiated therapy after POD24 to first-line bendamustine or CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) based IC. Observation, radiotherapy, or rituximab monotherapy were permitted prior to IC and pts with transformation prior to the subsequent therapy after IC were excluded as per S1608. Outcomes of interest were overall and complete response rate (ORR/CR), progression-free survival (PFS), and overall survival (OS). Results: We identified 196 eligible pts with early progression to IC (39% antiCD20 Benda; 61% antiCD20 CHOP) who received subsequent therapy. Median age at post IC treatment was 57 years, 78% grade 1-2 FL. Treatments for pts with POD24 included CHOP- or Benda-based in 31%, salvage/hematopoietic stem cell transplant (HSCT) in 27%, novel therapies in 10% (including phosphatidylinositol 3-kinase inhibitors), antiCD20 monotherapy in 9%, and lenalidomide-based treatment in 8% (table); 21% of pts were treated on clinical trials. Across all treatments, ORR (CR) was 63% (37%) (95% CI: 55-70). At a median follow up of 6.2 years, 2 year PFS was 22% (95% CI: 17%-29%) and 5 year OS was 71% (95% CI: 65-79). Outcomes by regimen are shown in the table. Conclusions: Pts with FL experiencing POD24 following first-line IC are treated heterogeneously, with many pts still receiving IC as subsequent therapy. Despite modest CR rates and low 2-year PFS, 5-year OS appear to be improving compared to historical outcomes. This supports the ongoing need to investigate novel treatments in this population. [Table: see text]