全自动银增强原位杂交检测乳腺癌患者人表皮生长因子受体2基因状态

Automated silver-enhanced in situ hybridization detection assay for human epidermal growth factor receptor 2 gene status determination in breast cancer

目的 评价银增强原位杂交（SISH）用于乳腺癌患者人表皮生长因子受体2（HER2）基因扩增状态检测的可行性.方法 研究对象为2009年5-11月在中国医学科学院北京协和医学院肿瘤医院行手术治疗的63例乳腺浸润性导管癌患者（年龄32～64岁）,术前均未行放疗和化疗.取手术切除乳腺癌标本行全自动免疫组织化学染色检测HER2蛋白表达、SISH检测HER2基因状态,其中43例同时行荧光原位杂交（FISH）检测HER2基因状态.根据2007年美国临床肿瘤协会/美国病理家协会制定的标准评估检测结果,比较不同检测方法之间的符合率.结果 61例患者SISH检测结果满意,其中HER2蛋白表达阳性（3＋）的30例中SISH检测29例（97%）为HER2基因扩增;蛋白表达不确定（2＋）的11例中SISH检测2例（18%）为基因扩增,2例（18%）为基因扩增不确定;蛋白表达阴性（1＋/0）的20例SISH检测均为基因无扩增.43例行FISH检测者,HER2蛋白表达阳性（3＋）的21例中20例（95%）FISH检测为HER2基因扩增;蛋白表达不确定（2＋）的10例中1例FISH检测为基因扩增,3例为不确定;蛋白表达阴性（1＋/0）的12例FISH检测均为基因无扩增.43例患者的FISH与SISH检测结果比较,42例相符（基因扩增21例,基因扩增不确定2例,基因无扩增19例）,1例FISH检测为HER2基因扩增不确定而SISH检测为基因无扩增,总体符合率为98%.结论 SISH技术用于乳腺癌HER2基因状态检测结果与FISH相当,具有可行性和实际使用价值.

Objective To evaluate the concordance of human epidermal growth factor receptor 2 （ HER2） gene amplification in invasive breast cancer by the techniques of fluorescence in situ hybridization （FISH） and silver-enhanced in situ hybridization （SISH）. Methods A prospective study of 63 invasive breast cancer specimens excised between May 2009 and November 2009 was conducted by automated immunohistochemistry （ IHC） staining and bright field automated SISH. HER2 gene status was also examined by FISH in 43 cases. An evaluation was performed according to the ASCO/CAP guidelines （2007）. Results Among 63 breast invasive ductal carcinoma tested by automated SISH, 61 cases were successfully evaluated. Gene amplification was detected in 97% （29/30） HER2 protein expression positive （3 ＋ ） cases and in 18% （2/11） equivocal （2 ＋ ） cases. Two of 11 （18% ） HER2 expression 2 ＋ cases were equivocal for gene amplification. In 43 cases examined by FISH, HER2 gene amplification was detected in 95% （20/21） HER2 expression positive （3 ＋ ） cases and in one equivocal （2 ＋ ） cases. Three of 10 （30% ） expression 2 ＋ cases were equivocal for gene amplification. No gene amplification was detected in expression negative （1 ＋/0） cases by either SISH or FISH （0/20 and 0/12 respectively）. The results of SISH and FISH were identical in 42 cases examined by the above two techniques, including 21 HER2 gene amplification positive, 2 equivocal and 19 negative cases. One case was FISH equivocal and SISH negative. And the overall concordance between FISH and SISH was 98%. Conclusions There is high concordance rate between SISH and FISH results for assessing the HER2 gene amplification status of excised breast cancer specimens.However,SISH has more advantages and it is particularly suited for routine application in surgical pathology.