METHODS: A pathology database search was made to identify metastatic breast carcinoma reported in cytology specimens. A manual search was then done to identify cases of HER-2 low category, H&E cell block and HER-2 neu immunostain slides were retrieved for a total of 50 cases. Reviewer #1 and #2 independently interpreted HER-2 immunostain of all 50 cases. Only discordant cases were sent for reviewer-3 interpretation. All three were blinded by the metastatic site, and original HER-2 interpretation.
RESULTS: Of 50 cases, 11 cases (22%) were reported as concordant scores between reviewer #1 and reviewer #2 but had a discordant original IHC report. Additionally, 4 cases (8%) had discordant reporting of HER2 IHC stain between reviewer #1 and reviewer #2 making a total of 15 cases (30%) with overall discordant results.
CONCLUSIONS: This study highlights the interobserver variability of HER-2 immunostain interpretation for HER-2 low category of breast carcinomas. We recommend the need for more robust laboratory techniques including molecular for uniform identification of these unique targetable metastatic breast carcinoma groups.
方法:进行病理数据库检索,以确定在细胞学标本中报告的转移性乳腺癌。然后进行手动搜索以识别HER-2低类别的病例,共检索了50例H&E细胞块和HER-2neu免疫染色载玻片。1号和2号审稿人独立解释所有50例的HER-2免疫染色。只有不和谐的病例被送交审核员-3解释。这三个人都被转移部位蒙蔽了眼睛,和原始的HER-2解释。
结果:50例,11例(22%)报告为1号审阅者和2号审阅者之间的一致评分,但原始IHC报告不一致。此外,4例(8%)在1号审阅者和2号审阅者之间的HER2IHC染色报告不一致,总共15例(30%),总体结果不一致。
结论:本研究强调了HER-2低类型乳腺癌的HER-2免疫染色解释的观察者间差异。我们建议需要更强大的实验室技术,包括用于统一鉴定这些独特的可靶向转移性乳腺癌组的分子。