Burkitt’s Lymphoma in Korea: Clinical Manifestations and Efficacy of Modified CALGB 9251 Regimen (BNHL).

Background: Clinical manifestations of sporadic Burkitt’s lymphoma of Asia including Korea has not been well informed. When Korean patients with Burkitt’s lymphoma were treated following the protocol proposed by the Cancer and Leukemia Group B (CALGB) 9251, grade 4 mucositis was reported in every patient. Thus, we had modified CALGB 9251 protocol and named BNHL.

Aims: This study was aimed to show the clinical manifestations and to evaluate efficacy and toxicity of BNHL in patients with Burkitt’s lymphoma in a Korean single center.

Methods: Between January 1998 and July 2005, 25 patients who were diagnosed as Burkitt’s lymphoma at Asan Medical Center were available to evaluate the clinical features. Among 25 patients, 12 patients treated with BNHL were available. In BNHL protocol, we reduced the dose of methotrexate (1,500 → 1,000 mg/m²/day on Day 1) and etoposide (80 → 50 mg/m²/day on Day 4 and 5) in cycle 2, 4, and 6, and the dose of methotrexate (1,500 → 1,000 mg/m²/day on Day 1) in cycle 3, 5, and 7 from the protocol of CALGB 9251.

Results: Median age was 50.4 years (range: 17–77) and 15 patients were male. Among 25 Burkitt’s lymphoma, 20 patients had extranodal involvement, and 9 patients had 2 or more extranodal involvements. Extranodal sites were bone marrow, GI tract, genitourinary organ, bone, and lung, in decreasing order. Among total patients, 16 were in stage III or IV, and 9 were in stage I or II. Twelve patients had B symptoms, and 16 patients had high or high intermediate score of age adjusted international prognostic index (IPI). For 12 patients treated with BNHL, median follow-up duration was 13 months (range: 3–20 months). Among patients treated with BNHL, 9 patients achieved CR, and 3 patients achieved PR. The event free survival (EFS) rate at 1 year was 54% (95% CI, 39–69%) and median EFS was not reached. Among 9 patients who achieved CR, 2 patients were relapsed. Three patients died as a result of treatment-related complications (2 patients) or progressive disease (1 patient). Median overall survival (OS) was not reached yet, and 1-year OS rate was 64% (95% CI, 50–78%). All patients treated with BNHL had hematologic toxicities of grade 3 or 4 neutropenia/thrombocytopenia. Grade 3 or 4 non-hematologic toxicities were; mucositis (67%), infection (58%), hepatic toxicity (42%), peripheral neuropathy (25%), and azotemia (25%).

Conclusions: Korean patients with Burkitt’s lymphoma had worse age-adjusted IPI score than that in western countries. Extranodal involvements were more frequent. Despite these poor risk factors, BNHL modified from CALGB 9251 showed satisfactory efficacy and acceptable toxicities in Korean Burkitt’s lymphoma.