A multicenter, phase II study of R-THP-COP therapy for elderly patients with newly diagnosed, advanced-stage, indolent B-cell lymphoma.

The optimal combined chemotherapy regimen with rituximab has yet to be established for elderly patients with advanced-stage indolent B-cell lymphoma (B-NHL). A multicenter study was performed to evaluate the efficacy and toxicity of R-THP-COP therapy in elderly patients (aged 70-79 years) with newly diagnosed advanced-stage indolent B-NHL using the complete response rate (%CR) as the primary endpoint. Patients with newly diagnosed, clinical stage III/IV, indolent B-NHL, aged 70-79 years, with a performance status of 0-2 were eligible for this study. R-THP-COP consists of 375 mg/m of rituximab, 50 mg/m of pirarubicin, 750 mg/m of cyclophosphamide, 1.4 mg/m of vincristine, and 100 mg/day of oral prednisolone for 5 days. This study was discontinued due to poor accrual after the enrollment of 18 patients, although the planned sample size was 40 patients. The numbers of patients with follicular lymphoma, mucosa-associated lymphoid tissue lymphoma, and mantle cell lymphoma were 16, 1, and 1, respectively. The median age was 73 (range, 70 to 79) years. The %CR including unconfirmed CR was 45% (95% confidence interval: 25-66%) and the overall response rate was 72%. The estimated 5-year overall survival and progression-free survival rates were 55% and 28%, respectively. The major toxicity observed was grade 4 neutropenia (94%). Grade 4 non-hematological toxicities were not observed and no patients developed grade 3/4 cardiac toxicities. This phase II study provides useful information regarding the efficacy and toxicity of R-THP-COP therapy for patients aged 70 years or older with newly diagnosed, advanced-stage, indolent B-NHL, although the sample size was small.