Impact of rituximab on treatment outcomes of patients with diffuse large b‐cell lymphoma: a population‐based analysis

We conducted a multi-institutional population-based analysis of the survival and toxicity associated with the addition of rituximab to chemotherapy for patients with diffuse large B-cell lymphoma (DLBCL), including patients aged ≥ 80 years, who were excluded from published randomized trials. Using population-based registries in Ontario, we identified 4021 patients who received chemotherapy with or without rituximab (R-CHOP rituximab with cyclophosphamide, doxorubicin, vincristine and prednisone or CHOP) for DLBCL between 1996 and 2007, including 397 patients aged ≥ 80 years. After propensity score matching, the overall survival (OS) and significant toxicities for R-CHOP and CHOP treatment groups were compared. R-CHOP was associated with a significant increase in 5-year OS compared to CHOP alone (62% vs. 54%; hazard of death = 0·78, P = 0·0004). Survival benefit was seen in all age groups, including those aged ≥ 80 years. Patients treated with rituximab did not have a significant increase in 1-year hospitalization rates for cardiac, pulmonary, gastrointestinal or neurological diagnoses compared to those treated with CHOP alone. The addition of rituximab to CHOP improves survival in the general population of patients with DLBCL and produces early survival benefit for very elderly patients, without any significant increase in the risk of serious toxicity.