The role of chemotherapy in diffuse aggressive lymphomas

Diffuse aggressive lymphomas are curable by combination chemotherapy in advanced stages, with 30% to 60% of all treated patients alive and disease free 2 to 5 years from the end of treatment, depending on the program used. The fact that combination chemotherapy can cure this disease has led, since 1975, to several new directions in therapy such as (1) the development of a variety of new combination chemotherapy programs, using older drugs more aggressively, adding additional drugs to each program, or manipulating the scheduling of drugs; (2) the close scrutiny of study results to identify risk factors that influence the ability to attain a durable complete remission; and (3) the use of combination chemotherapy in early stage disease instead of, or with, radiotherapy (RT). The recently developed aggressive programs have been reported to produce results superior to the original studies, but because important prognostic factors have only recently been identified, there remains some uncertainty about the significance of the reported differences between studies. Also, dose intensity, a poorly controlled treatment variable in all studies, has recently been identified as a significant factor affecting outcome. Schedule variation, while reported to exert some independent effect on outcome, appears to influence results by its effect on dose intensity. Regardless of the uncertainty over the ideal program for patients with advanced diffuse aggressive lymphoma, the results in early-stage disease have uniformly favored the use of combination chemotherapy as the primary treatment, with or without subsequent RT, depending on the quality of the response to drugs, reaffirming the invariable inverse relationship between cell number and curability by chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)