Prognostic value of the 3q27 and 18q21 translocations for diffuse large B-cell lymphoma and follicular lymphoma in the rituximab era.

Abstract

e18513 Background: The 3q27 and 18q21 translocations are major chromosomal alterations in B cell lymphoma. Bcl-6 on chromosome 3q27 encodes B-cell lymphoma (Bcl)-6 protein, which inhibits differentiation to plasma cells. The 18q21 translocation cause the constitutive activation and increased expression of the antiapoptotic Bcl-2 protein. However, the prognostic impact of these translocations in the rituximab (R) era is unclear. We aim to determine the frequency of the 3q27 and 18q21 translocations in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) and to evaluate their prognostic impact in the R era. Methods: The study included 93 patients with DLBCL and 98 with FL; they had abnormal karyotypes that had been detected using G-banding at diagnosis. The patients underwent R-CHOP therapy: doxorubicin, cyclophosphamide, vincristine, prednisolone, and R; median follow-up period was 29 months. Results: The 3q27 and 18q21 translocations were detected in 14 (15%) and 22 (24%), respectively, of the patients with DLBCL patients and in 14 (14%) and 77 (79%), respectively, of those with FL. The 2-year overall survival (OS) rates for patient with DLBCL and for those with FL were 79.0% and 95.1%, respectively; the 2-year progression-free survival (PFS) rates were 70.1% and 62.0%, respectively. The 2-year OS and PFS rates did not significantly differ between the 3q27, 18q21, and other chromosomal abnormality groups for DLBCL (2-year OS, 65.3% vs. 85.7% vs. 79.3%, respectively; 2-year PFS 59.2% vs. 65.4% vs. 73.6%, respectively; not significant) and FL (2-year OS, 85.7% vs. 94.7 vs. 100%, respectively; 2-year PFS, 42.9% vs. 64.0% vs. 60.6%; NS). These rates did not significantly differ between the patients with 3q27 translocation-positive DLBCL and those with 3q27 translocation-positive FL or between the patients with 18q27 translocation-positive DLBCL and those with 18q27 translocation-positive FL. Conclusions: In the R era, the presence of the 3q27 and 18q21 translocations is not correlated with the clinical outcome of patients with DLBCL or FL.