Rituximab Improves the Outcome of Patients with Grade 3 Follicular Lymphoma Receiving Anthracycline-based Therapy

Abstract Background The addition of rituximab to chemotherapy has improved the outcome of patients with follicular lymphoma (FL). However, data on grade 3 FL (FL3) and its subtypes are lacking. The aims of the study were to determine: 1) the clinical features and outcome of patients with FL3 treated with rituximab and anthracycline-based chemotherapy; and 2) the clinical significance of the three subtypes of FL3. Patients and Methods Eighty-seven FL1/2, 84 FL3 including 46 FL3A, 17 FL3B, and 21 follicular large cleaved cell (FL3C), and 411 diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab and anthracycline-based chemotherapy, and a historical cohort of 167 FL3 patients who received only anthracycline-based chemotherapy (FL3*) are included in this retrospective study. Results The FL3 group had a significantly better overall survival (OS) and event-free survival (EFS) compared to those with FL3* or DLBCL. No significant differences in OS were found among the three subtypes of FL3. However, FL3B had a shorter EFS than FL3A and FL3C. Moreover, FL3B had an outcome similar to DLBCL, whereas FL3A and 3C had significantly better outcomes than DLBCL. Less than 50% of the patients with FL3B and less than 20% of the patients with FL3A+3C have relapsed, and relapses were uncommon after five years. Conclusion The use of rituximab with anthracycline-based chemotherapy has significantly improved the survival of patients with FL3 and should be considered the benchmark by which other therapies for FL3 are evaluated in the future.