The clinical characteristics of B-cell lymphoma (BCL) were studied through the combined analysis of six clinical trials conducted by the Japan Clinical Oncology Group - Lymphoma Study Group (JCOG-LSG) for aggressive lymphoma in the 1990s, before the introduction of rituximab. Through a central pathological review, 829 patients were diagnosed with BCL according to the World Health Organization classification and treated with doxorubicin-containing combination chemotherapies. Of these patients, 642, 104, 30, and 24 patients were diagnosed with diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and marginal zone lymphoma (MZL), respectively. The overall survival (OS) of FL and MZL patients was higher than that of patients with DLBCL and MCL. The OS of the MCL patients was higher than that of DLBCL patients in the first 5 years, but MCL had the lowest survival after 5 years. The OS of DLBCL patients was clearly stratified by the international prognostic index and showed data compatible with that of aggressive lymphoma in the pre-rituximab era. These results established the clinical aspects of BCL in a large number of patients treated in prospective studies during the pre-rituximab era in Japan.
Keywords: B-cell lymphoma; aggressive lymphoma; clinical trials; diffuse large B-cell lymphoma; international prognostic index.