Clinical characteristics and prognosis of patients with co-existing follicular lymphoma and diffuse large B-cell lymphoma components in rituximab era

Purpose This single-centre study aimed to determine the clinicopathological characteristics and prognosis for patients with co-existing FL and DLBCL components (FL/DLBCL). Methods We retrospectively analysed the clinical characteristics and prognosis of patients diagnosed with FL/DLBCL (n = 56) and with pure FL (n = 260) or de novo DLBCL (n = 812) (controls) between January 2013 and December 2021. Results The median age of patients with FL/DLBCL was 52 years. The amount of the DLBCL component ranged from 5 to 95%. Among the 56 FL/DLBCL cases analysed, 67.9% were of germinal centre B-cell (GCB) origin, 26.8% non-GCB origin, and 5.3% were unclassified. The clinical features of patients with FL/DLBCL were intermediate, falling between those of FL and DLBCL. Propensity-score matching was performed for patients with similar baseline characteristics who were receiving the rituximab plus cyclophosphamide, doxorubicin or epirubicin, vindesine, and prednisone (R-CHOP) regimen. Patients with FL/DLBCL showed inferior outcomes compared to those with FL, with a lower complete remission (CR) rate, progression-free survival (PFS), and overall survival (OS). Bone marrow involvement and B symptoms were identified as independent adverse prognostic factors for PFS among patients with FL/DLBCL. Patients with FL/DLBCL presented a lower CR rate and PFS but similar OS to those with DLBCL when receiving the R-CHOP regimen. Conclusion Patients with FL/DLBCL showed inferior treatment response and survival than those with pure FL and had a lower CR rate and PFS, but similar OS to those with DLBCL in the rituximab era.

Automated summary

This study aimed to investigate the clinicopathological characteristics and prognosis of patients with co-existing FL and DLBCL components (FL/DLBCL). The results showed that patients with FL/DLBCL had intermediate clinical features between FL and DLBCL, and had inferior treatment response and survival compared to pure FL. However, when receiving the R-CHOP regimen, patients with FL/DLBCL showed similar overall survival to those with DLBCL.