Immunochemotherapy: the new standard in aggressive non-Hodgkin's lymphoma in the elderly

Rituximab is an anti-CD20 chimeric monoclonal antibody that has shown substantial activity in indolent non-Hodgkin's lymphoma (NHL). Recent data indicate that the clinical benefits achieved in the treatment of indolent NHL are mirrored in aggressive NHL. Diffuse large B-cell lymphoma is the most common form of aggressive NHL and accounts for approximately 40% of all NHL cases. Although rapidly fatal if left untreated, diffuse large B-cell lymphoma is responsive to chemotherapy. CHOP has been the gold standard of care in aggressive NHL for over 20 years and, until recently, efforts to improve efficacy have not resulted in substantial increases in clinical benefit. However, long-term survival is seen in less than 50% of patients, highlighting the need for novel therapeutic strategies. The activity of single-agent rituximab in pilot trials in the aggressive setting and its potential to sensitize tumor cells to the effects of chemotherapy, together with its non-overlapping safety profile, have encouraged investigators to combine rituximab with CHOP. The addition of rituximab to CHOP chemotherapy has achieved impressive survival benefits in elderly patients with untreated diffuse large B-cell lymphoma compared with CHOP alone. Importantly, improved response and survival were achieved with minimal additional toxicity, suggesting that immunochemotherapy provides a new standard of care in aggressive NHL. This article reviews the activity of rituximab in aggressive lymphoma and highlights its potential in both previously untreated and relapsed disease.