Impact of Cell of Origin Classification on Survival Outcomes after Autologous Transplantation in Relapsed/Refractory Diffuse Large B Cell Lymphoma

Abstract

The cell of origin (COO) classification into germinal center B cell (GCB) and non-GCB types has been shown to predict survival outcomes in newly diagnosed diffuse large B cell lymphoma (DLBCL). In the relapsed/refractory (R/R) setting, there is building evidence that COO does not predict prognosis after high-dose chemotherapy and autologous stem cell transplantation (auto-SCT). The present analysis aimed to compare survival outcomes based on COO classification in R/R DLBCL patients who underwent auto-SCT. This retrospective study included adult patients with R/R DLBCL who underwent auto-SCT at MD Anderson Cancer Center between January 2007 and December 2016. The Hans algorithm using CD10, BCL6, and MUM1 markers was used to classify patients by COO. A total of 122 patients with DLBCL (71 GCB, 51 non-GCB) were included in the analysis. There were no significant differences in patient characteristics between the 2 groups, except for older median age in the GCB cohort (64 years versus 58 years; P < .004). The median overall survival (OS) time was 68.5 (95% confidence interval [CI], 51.3 to not reached) months for the total population, 68.5 (95% CI, 44.8 to not reached) for GCB, and not reached for non-GCB. The 3-year OS rate was 0.659 (95% CI, 0.575 to 0.755) for the total population, 0.653 (95% CI, 0.547 to 0.779) for GCB, and 0.666 (95% CI, 0.537 to 0.824) for non-GCB. When adjusted for age and other factors of interest, no statistically significant associations for OS or progression-free survival were observed between the 2 cohorts. Our results confirm that COO loses its prognostic potential in patients with R/R DLBCL who receive high-dose chemotherapy followed by auto-SCT and both GCB and non-GCB types of DLBCL derive similar benefit from auto-SCT. Younger age, female sex, and pretransplantation disease status were associated with better OS.

Keywords: Autologous stem cell transplant; Cell of origin; Diffuse large B cell lymphoma; Gene expression profiling.