The study was set up to assess the efficacy and tolerability of a chemotherapy-immunotherapy combination programme originally introduced by GMALL (the German cooperative group for adult acute lymphoblastic leukemia)in 2002, to improve remission rate, overall and disease-free survival rates of adult patients with Burkitt's leukemia and lymphoma.

The therapy includes a maximum of six chemotherapy courses (two with high doses of methotrexate and cytarabine) plus anti-CD20 antibody (Rituximab, up to 8 total doses), supplemented by local radiation therapy in the case of initial mediastinal or central nervous system (CNS) involvement or a residual tumor after chemotherapy.

Cycle A1: prednisone-cyclophosphamide pre-phase (5 days), Rituximab on day 0, chemotherapy on days 1-5 (dexamethasone, iphosphamide, vincristine, high-dose methotrexate, triple intrathecal therapy).

Cycle B1: Rituximab on day 0, chemotherapy on days 1-5 (dexamethasone, vincristine, cyclophosphamide, high-dose methotrexate, adriamycin, triple intrathecal therapy) Cycle C1: Rituximab on day 0, chemotherapy on days 1-5 (dexamethasone, vindesine, high-dose methotrexate, etoposide, high-dose cytarabine).

Cycle A2: like cycle A1, without pre-phase. Cycle B2: like cycle B1. Cycle C2: like cycle C1. Cycle C2 is followed by two additional Rituximab injections.

Notes:

1. patients with stage I-II disease without mediastinal tumor or extranodal involvement receive only the first 4 cycles (A1 to A2).
2. patients aged >55 years do not receive cycles C (sequence: A1, B1, A2, B2, A3, B3 or A1, B1, A2, B2 if limited stage, with reduced-dose methotrexate).

Inclusion Criteria:

• Burkitt's leukemia or lymphoma (new diagnosis)
• Written informed consent
• Age > 15 years

Exclusion Criteria:

• pre-treated Burkitt's leukemia or lymphoma
• psychiatric disorders
• active second malignancy
• pregnancy
• absence of patient's written informed consent
• participation in other studies that interfere with the study therapy