Disparities In Receipt Of Radiotherapy and Survival By Age, Sex and Ethnicity Among Patients With Localized Diffuse Large B-Cell Lymphoma

Combination therapy with 3 cycles of chemotherapy followed by involved field radiotherapy has been a standard of care for treatment of localized diffuse large B-cell lymphoma (Miller TP NEJM 1998). This population based study evaluated ethnic disparities in receipt of radiotherapy (RT) and its effect on survival in patients with localized diffuse large B cell lymphoma (DLBCL) in the United States.The Surveillance, Epidemiology, and End Results database was reviewed to identify patients with stage I DLBCL diagnosed between 1998 and 2008. We used unadjusted and adjusted odds ratio (OR) to analyze association of receipt of radiotherapy with age (<60 and 60+ years), sex and ethnicity (White, Black and Others). We calculated relative survival rates for different cohorts using SEER*Stat software. We used cox’s proportional hazard model to investigate the impact of age, sex and ethnicity on survival rates.A total of 11763 patients with localized DLBCL as the only primary malignancy were included in the study. Of the cohort, 38.2% received radiotherapy. Receipt of radiotherapy varied significantly by patient ethnicity - whites were more likely to receive RT compared to blacks and others. Similarly, age <60 years and females were more likely to receive radiotherapy compared with older patients and males (Table – 1).The 1- and 5- year relative survival rates for patients receiving RT were higher compared to those who did not receive RT: 88.3±0.5% vs 73.4±0.6%, p-value <0.0001 at 1-year and 77.8±0.8% vs 62.5±0.7%, p-value <0.0001 at 5-years. Among patients who received RT, 1- and 5- year relative survival rates were significantly higher in whites compared to black or other- race patients.This population based study showed that only 38.2% of patients with localized DLBCL received radiotherapy. White patients were more likely to receive RT compared to blacks and others. Survival rates are significantly higher for patients who received RT.No relevant conflicts of interest to declare.