Treatment patterns and survival outcomes in US veterans aged ≥80 with newly diagnosed diffuse large B-cell lymphoma.

Abstract

e19072 Background: The optimal management of older patients with cancer remains a significant unmet need. This is exemplified in Diffuse Large B-Cell Lymphoma (DLBCL), where over 1/3 rd of new diagnoses occur in those age ≥75, yet older patients have comparatively inferior outcomes. This disparity is likely multifactorial, but in part due to underrepresentation of elderly patients in clinical trials and lack of a standard of care. We hypothesize that treatment strategy and survival may vary by area of residence in the US. We describe one of the largest analyses of treatment patterns and survival outcomes of patients age ≥80 with newly diagnosed DLBCL using Veterans Affairs (VA) data. Methods: We conducted a retrospective study of veterans age ≥80 diagnosed with Stage II-IV DLBCL between 2006-2023using the Veterans Affairs (VA) Cancer Registry System (VACRS). Patient, disease, and treatment characteristics were extracted from the VA Corporate Data Warehouse (CDW) and via chart review. Regimens were classified as curative (RCHOP, RminiCHOP, RCVP, miniRCVP, BR) or palliative (Rituximab, glucocorticoids, radiation). Veteran residence was classified by rurality per rural-urban commuting area (RUCA) codes. Variables were compared using the Chi-square test. Kaplan-Meier analyses with log-rank testing were performed to evaluate overall survival (OS). Results: A total of 612 Veterans were identified. A random sample of 181 charts were manually reviewed. In this sample, 98.3% (n=178) were male and 60.2% (n=109) resided in an urban area. 6.6% (n=12) of veterans were not offered anticancer treatment and 18.8% (n=34) of veterans did not start lymphoma-directed therapy. Of those offered treatment, 84.4% (n=124) were offered a curative regimen and 15.6% (n=24) a palliative regimen. Of those on treatment, 82.8% (n=111) initiated a curative regimen, including 55.2% (n= 74) starting an anthracycline regimen, and 14.2% (n=19) initiated a palliative regimen. Only 61% completed ≥6 cycles. Pre-phase steroids (2.8%, n=5) and geriatric assessments (0.6%, n=1) were rarely used. The complete response rate was 37.6%. Median OS was significantly higher for veterans who were treated with curative intent (2.8 yrs vs 0.36 yrs, p<.001). Although not statistically significant, more urban residents were offered a curative regimen (68.8% vs 61.5%, p=0.86) and started treatment compared to rural veterans (75.2% vs 65.4%, p=0.38). There was no difference in mOS between urban and rural veterans (p=0.44). Conclusions: Most veterans age ≥80 with DLBCL are offered treatment and start a curative regimen; however, many do not complete a full course. There was no statistically significant difference in treatment practice and OS by area of residence. Pre-phase steroids and geriatric assessments are underutilized, and wider adoption of these strategies could improve outcomes.