Feasibility and outcomes after dose reduction of immunochemotherapy in young adults with Burkitt lymphoma and leukemia: results of the BURKIMAB14 trial

High dose-intensive or infusional intermediate-dose immunochemotherapy is highly effective treatment for Burkitt lymphoma (BL) irrespective of human immunodeficiency virus (HIV) infection. However, toxicities of these regimens are relevant, especially in older adults and elderly patients. The prospective multicenter BURKIMAB14 trial included 4-6 blocks of immunochemotherapy according to stage (localized: I and II non-bulky; advanced: II bulky, III, IV) and age, with dose reduction in patients >55 yrs. Dose-intensity of chemotherapy was reduced in patients ≤55 yrs. after achieving complete metabolic response (CMR), and their outcomes were compared with those of similar patients included in the former BURKIMAB08 trial, in which there was no dose reduction. CMR was attained in 86/107 (80%) patients (17/19 in localized stages and 69/88 in advanced stages). Patients from the BURKIMAB14 trial ≤55 yrs. showed a similar OS and fewer infections and cytopenias than patients from the BURKIMAB08 trial. Patients >55yrs. had a significantly higher treatment-related mortality despite dose reduction of chemotherapy. With a median follow-up of 3.61 yrs. the 4-yr. overall survival (OS) probability was 73% (63%-81%). Age (≤55 yrs. vs. >55 yrs.) and stage (localized vs. advanced) had prognostic significance. No significant differences in OS were observed in HIV-positive vs. -negative patients. The results of BURKIMAB14 are similar to those of other dose-intensive immunochemotherapy trials. Age >55 yrs. and advanced stage, but not HIV infection, were associated with poor survival. Dose reduction of chemotherapy in young adults in CMR is safe and does not impact outcomes.