Burkitt leukemia limited to the bone marrow has a better prognosis than Burkitt lymphoma with bone marrow involvement in adults.

Burkitt lymphoma patients with bulky disease often have bone marrow involvement. However, leukemic presentation of Burkitt lymphoma in the absence of a mass (pure Burkitt leukemia; PBL) is uncommon. Both PBL and Burkitt lymphoma/leukemia, presenting with a tumor mass and marrow involvement (BLL), are considered stage IV disease, which is associated with a poor prognosis. However, there is limited information on the prognosis in adults with PBL because they have typically been included in cohorts of patients with BLL. This study identified 23 patients, which included 10 PBL and 13 BLL cases. Complex karyotypes (100%) were seen in all BLL cases compared to the PBL group (40%; p = 0.061). Patients with PBL had a significantly better 5-year overall survival of 87.5% vs only 24.3% in the BLL group (p = 0.005). The 5-year overall survival of patients with PBL treated with intensive chemotherapy is superior to those with BLL who are similarly treated.