Achieving 95% Cross-Methodological Concordance in HER2 Testing Causes and Implications of Discordant Cases
Achieving 95% Cross-Methodological Concordance in HER2 Testing Causes and Implications of Discordant Cases
复制标题
DOI：
10.1309/ajcpuqb18xzohhbj
复制
发表时间：
2010-08-01
影响因子：
3.5
通讯作者：
Allison, Kimberly H.
中科院分区：
文献类型：
--
作者：
Grimm, Erin E.;Schmidt, Rodney A.;Allison, Kimberly H.
我们感兴趣的是确定荧光原位杂交（FISH）和先前验证的免疫组化HER 2检测之间的一致性，以确定不一致的可能原因，并确定美国临床肿瘤学会/美国病理学家学会指南是否解决了所有不一致的原因。我们回顾了697例（2004-2007年）同时进行HER 2免疫组化和FISH检测的病例。非可疑免疫组化和FISH结果之间的总体一致性为96%。在19例不一致的病例中，13例（68%）被解释为免疫化学阳性，但FISH阴性。染色强度弱、颗粒染色和挤压伪影区域的判读被确定为最常见的问题。在被解释为免疫化学阴性和FISH阳性的6例病例中，2例来自已知在活检时接受曲妥珠单抗治疗的患者，1例非常接近FISH可疑类别，4例病例每个细胞的CEP 17信号少于1.5个（该组中1例患者还接受曲妥珠单抗治疗）。关注HER 2免疫组化解释的问题可以提高免疫组化阳性病例的一致率，但生物学原因可能解释一些不一致的免疫组化阴性病例。
We were interested in determining our concordance between fluorescence in situ hybridization (FISH) and a previously validated immunohistochemical HER2 assay to identify possible reasons for discordance and to determine if all reasons for discordance were addressed by the American Society of Clinical Oncology/College of American Pathologists guidelines. We reviewed 697 cases (2004-2007) in which HER2 immunohistochemical and FISH testing were concurrently done. Overall concordance between nonequivocal irnmunohistochemical and FISH results was 96%. Of the 19 discordant cases, 13 (68%) were interpreted as positive immunohistochemically but negative by FISH The primary reason for this discordance was immunohistochemical interpretation. Weak stain intensity, granular staining, and interpretation in areas of crush artifact were identified as the most common issues. Of the 6 cases interpreted as immunohistochemically negative and FISH-positive, 2 were from patients known to be receiving trastuzumab at the time of biopsy, 1 was very close to the FISH equivocal category, and 4 cases had fewer than 1.5 CEP17 signals per cell (1 patient in this group was also receiving trastuzumab). Focusing on issues with HER2 immunohistochemical interpretation can improve concordance rates for immunohistochemically positive cases, but biologic reasons may explain some discordant immunohistochemically negative cases.