Anti-CD20 monoclonal antibody as a new treatment modality for B-cell lymphoma

Patients with follicular non-Hodgkin's lymphoma (NHL) generally have an indolent clinical course and respond well to standard chemotherapeutic regimens. However, the response duration is rather short. There has been no therapeutic regimen superior to CHOP chemotherapy for aggressive NHL in past 20 years. Novel therapeutic strategies are necessary for these types of B-cell lymphomas which express CD20 antigen on the surface of tumor cells. Chimeric human/mouse anti-CD20 monoclonal antibody, rituximab, has a powerful therapeutic activity with minimal adverse reaction in B-cell lymphoma through complement-dependent cytotoxicity (CDC) or antibody-dependent cell-mediated cytotoxicity (ADCC) and apoptotic mechanisms. The combination of rituximab and CHOP chemotherapy produced a high response rate (95%) in patients with indolent B-cell NHL and prolonged the progression-free and overall survivals in patients with diffuse large-B-cell lymphoma. Confirmation of CD20 expression of tumor cells is essential to predict the response to rituximab in B-cell lymphoma.