The academic center effect: Better outcomes for patients with DLBCL

Abstract Background Approximately 5 per 100,000 people per year will develop Diffuse Large B-Cell Lymphoma (DLBCL) making it the most frequent subtype of non-Hodgkin lymphoma worldwide (DLBCL-Cancer STAT Facts; Blood PMID9166827). Given its high incidence, hematologists are generally familiar with the diagnosis and treatment. However, the wide variability in disease characteristics contributes to a broad spectrum of clinical outcomes(Clin Lymphoma Myeloma Leuk PMID32067954). Combination chemotherapy is effective in curing a significant proportion of patients, with multiple protocols and subsequent options available based on molecular profiling(Leuk Lymphoma PMID7940576). To our knowledge, this is the largest study in the United States (US) analyzing demographics, clinical characteristics, and survival outcomes of patients treated at Academic Cancer Programs (ACP) versus Community Cancer Programs (CCP), evaluating the impact of facility type on outcomes in DLBCL. Methods A retrospective analysis of patients diagnosed with DLBCL in the US from 2004 to 2022 was conducted using the National Cancer Database. Demographics, treatment patterns, and outcomes were compared between ACP and CCP. ACP included Academic and Research Programs, including NCI-designated Comprehensive Cancer Centers. CCP included Community Cancer Programs, Comprehensive Community Cancer Programs, and Integrated Network Cancer Programs. Kaplan-Meier and Cox regression analyses were used to compare overall survival (OS) between the two cohorts. Variables used for adjustment included age, ethnicity, insurance status, distance from hospital, and Charlson-Deyo comorbidity score. Results 311,188 patients with DLBCL were identified, 160,336 treated in ACP and 130,645 in CCP. Data was not available for 20,207 cases; therefore, it was not included in the analysis. Most of the cases in both groups were male, with median age at diagnosis of 68 years (y) for ACP and 71y for CCP P0.001. In ACP the majority (41%) were in the age group from 60-75y at the time of diagnosis, for CCP most (40%) belonged to 75y P0.001. The most common race for both cohorts was White (85% and 90%), followed by Black (8% and 5%). Regarding ethnicity only 8% and 6% identified as Hispanics for ACP and CCP, respectively P0.001. Primary payer at diagnosis for ACP was Medicare (55%), followed by Private (33%), Medicaid (6%), uninsurance (3%) and other (3%). For CCP it had the same pattern with difference on the distribution: 62%, 29%, 4%, 2% and 2%, respectively. Most of the patients were located in the metropolitan area, 82% for ACP and 76% in CCP, with distance from the hospital in miles to be 10.9 vs 8.5, respectively P0.001. Patient's functional status was appropriate in both groups (Charlson Deyo score of 0-1), 89% in ACP and 88% in CCP. Stage IV was most common at diagnosis: 39% in ACP vs 34% CCP P0.001. The median time from diagnosis to initiation of treatment was 17 days for both ACP and CCP. Patients in ACP group were more likely to receive treatment, 69% compared to 63% in CCP P0.001. In adjusted survival analyses, patients treated at ACP demonstrated significantly superior outcomes in relation to those treated at CCP. Two-year OS was 65% at ACP vs 63% at CCP, 5-y OS was 54% vs 52%, and 10-y OS was 40% vs 38%, respectively. The median OS was 6.4y at ACP vs 5.8y at CCP P0.001. Median follow-up time, measured as the interval from diagnosis to last contact, was longer in the ACP cohort (38 months vs 33 months, P0.001). Conclusions: Treatment at ACP is associated with superior survival outcomes in DLBCL, even after adjusting for demographic and clinical variables. Patients treated at ACP were younger, more racially and ethnically diverse, frequently diagnosed with advanced-stage disease, and more likely to receive systemic therapy; despite these potentially adverse features, OS was significantly better. The effect of ACP in survival is likely a result of comprehensive, multidisciplinary care, coordinated supportive services, advanced diagnostics, possible fewer barriers to drug coverage and insurance, and access to lymphoma specialists and clinical trials. These findings emphasize the need to expand access to high-quality oncology care by enhancing CCP-ACP partnerships, referral pathways, and clinical trial enrollment. Strategic collaboration may help reduce care disparities and improve clinical outcomes for patients with DLBCL.