Burkitt lymphoma in children: the Israeli experience.

Background: We analyzed the results of the French-American-British-LMB 96 protocol performed in 9 centers in Israel on 88 patients with B-cell non-Hodgkin lymphoma treated from 2000 to 2005.

Procedure: The majority of the patients was male (63/88, 72%), with a median age of 8.9 years (range, 2.5 to 20 y). Ethnic origin was Jewish in 73% (64/88), and Arabic in 27%. Fifty (57%) patients were classified as Burkitt lymphoma, 5 (5.7%) as Burkitt-like lymphoma, 22 (25%) as diffuse large B cell (DLBC), and 9 (10.2%) as Burkitt leukemia with over 25% of their bone marrow (BM) involved. Initial disease sites included the abdomen in 43%, head and neck in 45%, and mediastinum in 7%. Stage I: 9.1%; stage II: 28.4%; stage III: 45.5%, stage IV: 17%. Two patients had BM involvement alone, 5 patients had central nervous system (CNS) involvement alone, and 4 had both CNS and BM. The children were divided into 3 groups according to risk factors, with 5 in group A, 69 in group B, and 14 in group C.

Results: With a median follow-up of 3 years (12 mo to 7.6 y), the Kaplan-Meier for event-free survival (EFS) and overall survival (OS) according to whole group treatment was 88.6% and 90.9%, group A was 100% and 100%; group B was 89.9% and 92.8%; and group C was 78.6% and 78.6%. There were no untoward events or deaths in group A, whereas 6 patients relapsed in group B, 4 of whom died (all relapsed during the first year), with tumor lysis syndrome in 3 patients and death of toxicity in 1 patient who had multiorgan failure 2 days after initiation of COP. Three patients in group C relapsed and died (all patients relapsed during the first 6 months), with tumor lysis syndrome in 4 patients but no deaths from toxicity. EFS for LDH less than twice was 96.4%, EFS for LDH more than twice was 73.3% (P=0.002). OS according to primary site: bone and ovary: 100%; head and neck: 95%; abdomen: 92%; mediastinum: 50%. The difference between the mediastinal primary site to all other primary sites was statistically significant with P=0.003. All the mediastinal tumors were of DLBC origin but no significant differences in outcome were found when DLBC was compared with other histologies (DLBC: 81.8%, other B line: 90.9%). OS for patients of Arabic ethnic origin was 79.2%, for Jewish patients was 95.3%, P=0.02. We could not determine any prognostic factors that were different between the groups, which raises the question of a genetic influence.

Conclusions: In nonresected mature B-cell lymphoma of childhood and adolescence with no BM or CNS involvement, a 93% cure rate can be achieved, similar to the French-American-British/LMB 96 trial. Patients with primary DLBC mediastinal mass had a significantly reduced OS, indicating the need for a different therapeutic approach.