Impact of chemotherapy regimen and rituximab in adult Burkitt lymphoma: a retrospective population-based study from the Nordic Lymphoma Group.

Background: Standard treatment of adult Burkitt lymphoma is not defined due to the lack of randomised trials. In this situation, population-based data may represent a useful contribution in order to identify an optimal treatment strategy.
Patients and Methods: The aims of this study were to investigate the outcome for adult HIV-negative BL with different chemotherapy regimens, and to assess possible improvement within the time frame of the study. The study population was identified through the Swedish and Danish lymphoma registries 2000-2009.
Results: A total of 258 patients were identified. Since 2000, overall survival (OS) improved significantly only for younger patients (<65 years). Intensive regimens such as the Berlin-Frankfurt-Münster, hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) and cyclophosphamide, vincristine, doxorubicin, methotrexate, ifosfamide, etoposide, and cytarabine (CODOX-M/IVAC) were associated with a favourable 2-year OS of 82%, 83%, and 69%, respectively. The low-intensive CHOP/CHOEP regimens achieved a 2-year OS of 38.8%, confirming their inadequacy for the treatment of BL. In a multivariate analysis, rituximab was not significantly associated with improved OS.
Conclusions: In this population-based retrospective series of adult BL, intensive chemotherapy regimens were associated with favourable outcome. The impact of the addition of rituximab remains uncertain and warrants further investigation.