The Under-Treatment of Elderly Medicare Diffuse Large B-Cell Lymphoma Patients

Prior real-world data show that a large proportion of the elderly population with diffuse large b-cell lymphoma (DLBCL) are not receiving the recommended therapy for their disease. Over half of the patients diagnosed with DLBCL are over the age of 60 and clinical trials show that patients over the age of 60 respond well to current guideline-based therapy. We set out to examine the patient characteristics associated with receiving recommended therapy and the survival outcomes in an older population in routine clinical practice.

We conducted a retrospective cohort analysis of 9866 DLBCL patients in the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Patients were diagnosed between January 1, 2000 to December 31, 2007, were >66 years, and continuously enrolled in Medicare Part A and B with no HMO coverage in the year prior to diagnosis. Chi-square test for categorical variables and ANOVA or t-test for continuous variables were used to assess differences in patient and disease characteristics by treatment status. Logistic regression modeling assessed the patient characteristics predictive of not receiving treatment. Kaplan-Meier curves and Cox proportional hazards regression assessed survival by treatment type. Date of last follow-up was December 31, 2009.

There were 7832 (80%) patients who received treatment and 2034 (20%) who did not receive treatment during the study time period. Untreated patients were older at diagnosis with mean age of 81 compared to 76 years in treated patients (p<.0001). As age increased, the treatment rate significantly decreased especially among patients >80 years (Table 1). Untreated patients were also more likely non-white (15% vs. 12%; p<.01), diagnosed with stage IV disease (33% vs. 29%; p<.0001), had higher comorbidity burden, and lived in areas of lower socioeconomic status than treated patients (p<.0001). In the adjusted logistic regression model, increasing age, non-white race, higher comorbidity score, and lower income were predictive of not receiving treatment. The multivariate survival analysis, adjusting for age, sex, race, stage, histology, comorbidity, income, and year of diagnosis, demonstrated a 3-fold higher risk of death in the untreated patients (HR=2.98; 95%CI=2.81–3.16) compared to treated patients.

This real-world analysis of elderly DLBCL patients confirmed that 20% of them are not receiving treatment, and the rate of under-treatment is even more pronounced among those >80 years. As a consequence, untreated patients had a 3-fold higher risk of death compared to those who received treatment.

Satram-Hoang:Genentech, Inc.: Consultancy. Skettino:Genentech, Inc.: Employment, Roche Stock Other. Reyes:Genentech, Inc.: Employment, Roche Stock Other.