Department of Pathology, Hospital Pedro Hispano, ULS Matosinhos, Rua Dr. Eduardo Torres, 4464-513, Senhora da Hora, Matosinhos, Portugal.
Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal; I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
Pathol Res Pract. 2020 Sep;216(9):153090. doi: 10.1016/j.prp.2020.153090. Epub 2020 Jun 29.
To characterize a cohort of gastro-esophageal adenocarcinomas (GEA) evaluated for HER2 gene amplification using bright field in situ hybridization (ISH) following the 2016 guidelines for GEA and correlating the results with clinico-pathological features. It was also aimed to evaluate the effect of applying the ISH criteria from the 2018 guidelines for breast cancer (BC) in the same GEA cases.
159 GEA cases collected in a period of 59 months were evaluated for HER2 gene amplification by ISH according to GEA and BC guidelines. All cases were reviewed for histological type, grading and presence of signet ring cells.
Most of the cases refereed to ISH were HER2 equivocal (57.9 %) by immunohistochemistry. According to the GEA guideline, 131 cases were HER2-negative (87.3 %) and 19 cases were HER2-positive (12.7 %). According to the BC guideline, 133 cases were HER2-negative (88.7 %) and 17 cases were HER2-positive (11.3 %), being statistically similar to the results obtained with the GEA guideline. HER2 genomic heterogeneity was detected in 31.6 % of the HER2-positive cases, almost exclusively in tubular adenocarcinoma. We observed a significant association between HER2 gene amplification and tubular adenocarcinomas, and absence of signet ring cells. The only case with HER2 gene amplification and presence of signet ring cells was a mixed carcinoma, where the signet ring cells represented the non-amplified component.
HER2 positivity rate was similar when applying the GEA or the BC guidelines. We also establish a tight association between morphology and HER2 gene amplification.
使用 2016 年胃食管腺癌（GEA）HER2 基因扩增检测指南中的明场原位杂交（ISH）对一组 GEA 病例进行特征描述，并将结果与临床病理特征相关联。还旨在评估在相同 GEA 病例中应用乳腺癌（BC）2018 年 ISH 标准的效果。
在 59 个月的时间内，收集了 159 例 GEA 病例，根据 GEA 和 BC 指南，通过 ISH 评估 HER2 基因扩增。所有病例均进行组织学类型、分级和印戒细胞存在的评估。
大多数经免疫组织化学检查被归类为 HER2 不确定（57.9%）的病例。根据 GEA 指南，131 例为 HER2 阴性（87.3%），19 例为 HER2 阳性（12.7%）。根据 BC 指南，133 例为 HER2 阴性（88.7%），17 例为 HER2 阳性（11.3%），与 GEA 指南获得的结果统计学上相似。在 31.6%的 HER2 阳性病例中检测到 HER2 基因的异质性，几乎仅在管状腺癌中存在。我们观察到 HER2 基因扩增与管状腺癌和无印戒细胞之间存在显著关联。唯一一例存在 HER2 基因扩增和印戒细胞的病例为混合癌，其中印戒细胞代表未扩增的成分。
应用 GEA 或 BC 指南时，HER2 阳性率相似。我们还建立了形态学与 HER2 基因扩增之间的紧密关联。
