Effect of Adding Immunotherapy (IT) to Treatment Regimen of Mantle Cell Lymphoma (MCL): Analysis of the National Cancer Data Base (NCDB).

e19022 Background: There has been some improvement in overall survival (OS) for patients with MCL over the past years [Gordon 2014]. However, side effects of treatment remain a major concern. With introduction of novel therapies like IT, it is imperative to optimize treatment regimens to improve survival while minimizing toxicity. Methods: MCL patients (pts) who were diagnosed in 2013 or later with information available about chemotherapy (CT) and IT and did not receive transplant were extracted from NCDB. Pts were assigned to age categories and were sorted into six groups based on different combinations of CT (none, single agent (SA), and multi-agent (MA)) with or without IT. Cox regression analysis was used to perform multivariate analysis that included age category, sex, race, clinical stage, Charlson/Deyo score, CT, radiation, and IT for each group. Multivariate p values (p) were used to analyze statistical significance. Kaplan Meier method was utilized to analyze OS. T-test was used to compare means (t-p). Results: 1438 total pts were identified with a mean age of 70 (range 24-90); 71% male; 93% white, 4% black, 3% others; 42% with stage III/IV disease. 667 pts did not receive CT or IT, and 40 received IT alone and both of these groups were excluded from further analysis. 52 pts received SA- (without) IT, 206 received SA+(with) IT and 260 pts received MA-IT and 213 MA+IT. Mean age was 72 and 66 for SA and MA groups, respectively (t-p<0.01). Mean OS for SA+IT was 27 months (m) vs SA-IT 16 m (p < 0.01). MA+IT v MA-IT showed no difference in mean OS (25 vs 26 m, respectively, p =0.49). Although there was a significant difference in OS between SA and MA groups without IT (16 vs 25 months, p < 0.01). SA + IT group showed comparable mean OS time to MA + IT (27 vs 26 m, p =0.145). Conclusions: For MCL pts, MA has superior OS to SA group. However, adding IT significantly improves OS for SA group and makes it comparable to MA. Adding IT to MA did not provide significant difference in OS. These results highlight the possibility of achieving same OS with less toxic regimens. Hence further evaluation in a prospective study to optimize treatment while reducing toxicity is warranted.