广西地区散发性乳腺癌BRCA1突变及其相关临床、组织病理特征的研究

目的：探讨广西地区散发性乳腺癌BRCA1基因的突变情况，及其与乳腺癌的临床、组织病理特征。方法：采用PCR联 合基因直接测序法检测广西地区235例乳腺癌患者（包括155例汉族及80例壮族乳腺癌患者）BRCA1基因的突变情况，同时 采用免疫组化方法检测乳腺癌组织中ER、PR及CerbB-2的表达情况。结果：①235例乳腺癌患者BRCA1突变率为8.5% （20/235）;其中汉族与壮族乳腺癌患者BRCA1突变率分别为7. 1 % （11/155）、11. 3% （9/80），两者比较差异无统计学意义（χ^2=1. 169，P =0. 280）。②20例BRCA1突变乳腺癌中CerbB-2阴性表达率为65. 0%，三阴性乳腺癌（TNBC）检出率为35.0%; 而无BRCA1突变乳腺癌中CerbB-2阴性表达率为30. 0%，TNBC检出率为14. 8%，两组比较Cerbfr2阴性表达率及TNBC检 出率差异有统计学意义（χ^2 = 10.031, P =0.002；χ^2=4.018, P =0.045）。结论：广西地区散发性乳腺癌BRCA1基因突变率 相对较低，汉族与壮族乳腺癌患者BRCA1突变率无明显差异；BRCA1突变乳腺癌CerbB-2阴性表达率高，与三阴性乳腺癌关 系密切，提示预后可能较差。

STUDY ON THE BRCA1 GENE MUTATION, ITS RELATED CLINICAL AND HISTOPATHOLOGICAL CHARACTERISTICS OF SPORADIC BREAST CANCER IN GUANGXI

Objective： To investigate the prevalence of BRCA1 gene mutations among sporadic breast carci-noma patients in Guangxi and to discuss the clinical and histopathological characteristics of BRCA1 gene mutation-associated breast carcinomas. Methods ： The BRCA1 gene mutations in 235 breast carcinoma cases （including 155 Han and 80 Zhuang cases） were detected by PCR-DNA sequencing and the expression levels of ER, PR and CerbB-2 were detected with immunohistochemistry. Results ： The prevalence of BRCA1 gene mutation of 235 cases was 8.5% （20/235）. There was no significant difference in prevalence of BRCA1 gene mutation between Han （7. 1%） and Zhuang cases （11. 3%,χ^2= 1. 169,P =0. 280）. Among 20 cases with BRCA1 gene mutations, the negative expression rate of CerbB-2 and the detection rate of tri-ple negative breast cancer （TNBC） were 65. 0% and 35. 0% , respectively while those of cases without BRCA1 mutation were 30. 0 % and 14. 8 %,respectively. There were significant differences in negative ex-pression rate of CerbB-2 and detection rate of TNBC among cases with and without BRCA1 mutation （χ^2 = 10. 031,P =0. 002; =4. 018, P =0. 045）. Conclusion： The prevalence of BRCA1 gene mutation among sporadic breast carcinoma patients in Guangxi is relatively lower and there was no significant difference in the prevalence of BRCA1 gene mutation between Han and Zhuang cases. BRCA1 gene mutation-associated breast carcinoma has higher negative expression rate of CerbB-2 and related closely to TNBC, which hints bad prognosis.