Low incidence of BCL-6 gene alterations for diffuse large B-cell lymphomas in Taiwan Chinese

✍ Scribed by Po-Min Chen; Muh-Hwa Yang; I-Ting Yu; Jen-Tsun Lin; Yu-Chen Lin; Frank S. Fan; Wei-Shu Wang; Chueh-Chuan Yen; Tzeon-Jye Chiou; Jin-Hwang Liu

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 269 KB
• Volume: 94
• Category: Article
• ISSN: 0008-543X
• DOI: 10.1002/cncr.10545

✦ Synopsis

Abstract

BACKGROUND

In Western populations, rearrangement of the BCL‐6 gene can be identified in 20–40% of patients with diffuse large B‐cell lymphoma (DLBCL). Analysis of the BCL‐6 gene has revealed the presence of point mutations or small deletions in 70% of DLBCL tumors; however, few studies have investigated BCL‐6 gene alteration in patients with non‐Hodgkins lymphoma (NHL) of Chinese descent.

METHODS

Samples from 135 Taiwanese patients with NHL were examined (28 samples of T‐cell NHL and 107 samples of B‐cell NHL; 59 samples from patients with DLBCL) for gene rearrangement and mutation of the BCL‐6 proto‐oncogene using Southern blot analysis and single‐strand conformation polymorphism (SSCP) followed by sequence analysis.

RESULTS

BCL‐6 rearrangement and point mutations were found in 14.8% of patients (n = 20) and in 7.4% of patients (n = 10), respectively. All BCL‐6 gene alterations occurred in patients with B‐cell NHL, and none occurred in patients with T‐cell NHL. Among the 59 patients with DLBCL, BCL‐6 gene rearrangements were identified in 10 patients (16.9%), and mutations were identified in 8 patients (13.6%), with the BCL‐6 mutation occurring independent of the BCL‐6 rearrangement. The incidence of BCL‐6 gene rearrangement and mutations in patients with extranodal DLBCL was 9.5% (2 of 21 patients) and 23.8% (5 of 21 patients), respectively. Univariate analysis and multivariate logistic regression found no association between BCL‐6 gene alternations and clinical characteristics, including extranodal tumors in patients with DLBCL, and no association between the BCL‐6 alterations and prognosis was found.

CONCLUSIONS

The incidence of BCL‐6 alterations was lower in Taiwanese patients with DLBCL compared with Western populations, and BCL‐6 gene alterations showed no prognostic significance in patients with DLBCL. Cancer 2001;94:2635–44. © 2002 American Cancer Society.

DOI 10.1002/cncr.10545