Phase II study of dose-adjusted gemcitabine, dexamethasone, cisplatin, and rituximab in elderly relapsed diffuse large B-cell lymphoma patients.

High-dose chemotherapy and autologous stem cell transplantation (ASCT) are too toxic for elderly patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL). Therefore, effective and tolerable regimens for elderly patients are urgently needed. The present phase II study assessed the efficacy and safety of dose-adjusted therapy with gemcitabine, dexamethasone, cisplatin, and rituximab (GDP-R) in this population. ASCT-ineligible elderly patients with relapsed or refractory DLBCL received dose-adjusted GDP-R in each 28-day cycle for up to six cycles. The primary endpoint was overall response rate (ORR), and secondary endpoints were complete response (CR) rate, progression-free survival (PFS), and safety. Thirty-three patients were enrolled and received dose-adjusted GDP-R. The median age was 75 years (range: 68-87 years). The ORR was 82.8% (90% confidence interval [CI], 67.1-93.0%), with a CR rate of 58.6% (90% CI, 41.7-74.1%). At a median follow-up of 20.9 months, the 2-year PFS rate was 46.8% (90% CI, 30.7-61.5%) and the 2-year overall survival rate was 63.2% (90% CI, 45.8-76.3%). The most frequently observed grade 4 adverse events were neutropenia (63.6%), thrombocytopenia (57.6%), and lymphocytopenia (39.4%). Dose-adjusted GDP-R is a promising salvage regimen for ASCT-ineligible elderly patients with relapsed DLBCL after rituximab-containing chemotherapy and warrants further investigation.