BCL-2 and MYC gain/amplification is correlated with central nervous system involvement in diffuse large B cell lymphoma at leukemic phase

Abstract

Background: Diffuse large B-cell lymphoma (DLBCL) of leukemic phase is a rare clinical manifestation, but is highly prevalent with central nervous system involvement (CNSI). Little is known about this rare clinical observation. Methods: We reviewed the clinical characteristics of 40 DLBCL patients with leukemic phase identified by flow cytometry and analyzed BCL2 and MYC aberrations by fluorescence in situ hybridization. Results: The median age of these 40 patients was 46 years (range, 15-75) with 19 men patients. All patients had bone marrow involvement, and fourteen (35.0%) had CNSI. There were respectively 14 patients (35.0%) had the BCL2 or MYC gain/amplification and nine of them (22.5%) simultaneously had both aberrations. Compared to those without CNSI, CNSI was found more commonly in male patients (71.4 vs. 34.6%, p = 0.046), in those with IPI scores of 4-5 (57.1% vs. 11.5%, p = 0.001), and in those with elevated serum LDH (100 vs. 61.5%, p = 0.007) and both MYC and BCL2 rearrangement (88.9 vs. 19.4%; p = 0.000). BCL2 and MYC rearrangements were the sole independent factor correlated with CNSI. Conclusion: It is possible that both BCL2 and MYC gene aberrations may contribute to the high incidence of CNSI observed in leukemic phase of patients with DLBCL.