Based on centroblast frequency, follicular lymphoma (FL) is subdivided into grades 1-2, 3A, and 3B. Grade FL3A frequently coexists with FL1-2 (FL1-2-3A). Based on clinical trials, FL1-2 is treated with rituximab (R) or obinutuzumab plus bendamustine (B) or CHOP, while FL3B is treated with R-CHOP. In contrast, there are little data guiding therapy in FL3A. We present a retrospective, multicenter analysis of 95 FL3A or FL1-2-3A and 203 FL1-2 patients treated with R-CHOP or R-B first-line. R-CHOP facilitated a higher response rate (95% versus 76%) and longer overall survival (OS) (3-year OS 89% versus 73%, P = 0.008) in FL3A or FL1-2-3A, whereas the difference in progression-free survival (PFS) did not reach statistical significance. While transformation rates into aggressive lymphoma were similar between both groups, there were more additional malignancies after R-B compared with R-CHOP (6 versus 2 cases). In FL1-2, R-B achieved a higher 3-year PFS (79% versus 47%, P < 0.01), while there was no significant difference regarding OS or transformation. With the limitations of a retrospective analysis, these results suggest a benefit for R-CHOP over R-B in FL3A or FL1-2-3A. Confirmatory data from prospective clinical trials are needed.
Keywords: Bendamustine; CHOP; Follicular lymphoma; Grade 3A; Rituximab.