The prognosis of Burkitt's lymphoma is generally considered to be poor, particularly in the advanced stages of the disease. Although recent chemotherapy protocols have given high rates of cure in children, there are few such reports concerning adults. We therefore conducted a retrospective analysis of the results for treatment of 46 adults in the Institut Gustave Roussy (IGR) between 1978 and 1987, in order to establish an effective treatment strategy for use in a prospective trial. The median age of the patients was 31 years and the majority were Caucasians of European origin. The clinical symptoms and course of the disease were similar to those in the pediatric situation and corresponded to the so-called non endemic forms observed in Europe and the United States. Presentation was generally extra-nodal, usually with abdominal manifestations. As a rule, the disease progressed rapidly and showed a high affinity for the central nervous system in the absence of specific prophylaxis, despite systemic therapy with highly active agents, particularly in the advanced stages. According to Murphy's classification, there were 6 stage I, 11 stage II, 19 stage III and 10 stage IV patients (3 of whom had CNS involvement). Treatment was heterogenous, although all the patients received polychemotherapy including anthracyclins. The best results were obtained from eleven patients treated according to the French Multicenter Protocols for pediatric Burkitt's lymphoma (LMB-84 and LMB-86). Kaplan-Meier 5-year relapse free survival rate among the 46 patients was 42% (stage I: 83%; stage II: 67%; stage III: 30%; stage IV: 30%). In order to standardize our therapeutic approach, we started a prospective study in 1988 using the unmodified pediatric protocol for our adult patients.