通过免疫组织化学证明胃腺癌 (GA) 组织中存在 HER2，有助于确定靶向治疗是否可以优化 HER2 阳性 GA 患者的治疗。然而，这还没有在我们的患者中进行广泛的研究，因此需要进行这项研究。受者组织微阵列块是由供体档案福尔马林固定石蜡包埋的胃肿瘤组织构建的，这些组织来自一项回顾性描述性研究，在 17 年的时间里观察到了 80 名患者。从这些块上切下的载玻片通过免疫组织化学用抗人 HER2 抗体染色，并使用胃腺癌 (ToGA) 试验标准中的曲妥珠单抗进行评分。还检索并回顾了胃腺癌的年龄、性别、病变部位和组织学亚型的数据。 80例（男52例，女28例；男女比例为1.9：1），55.65±13.50岁（众数年龄组60） -69年），进行了研究。大多数肿瘤（91.2%）累及胃的远端部分（幽门、胃窦和胃体），少数（8.8%）累及胃的近端部分（贲门和胃底）。仅 6 例 (7.5%) 病例中 HER2 过度表达。 7 个近端肿瘤中的 2 个 (28.6%) 显示 HER2 阳性，而 73 个远端肿瘤中只有 4 个 (5.5%) 显示 HER2 阳性。我们的 HER2 过表达率仅略低于世界许多其他地区的研究。观察到的近端肿瘤的过度表达显着高于远端肿瘤，表明远端肿瘤比近端肿瘤更不可能对曲妥珠单抗产生反应。已知的远端胃肿瘤与幽门螺杆菌感染之间的关联可能为 GA 发生部位的分子发病机制提供了可能的差异。近端胃癌发生的确切机制仍有待更清楚地阐明。建议进行更多研究，包括更大样本量的临床试验，以阐明 HER2 在胃腺癌中的这种差异表达。版权所有 © 2024，西非医学杂志。

The demonstration of HER2 in gastric adenocarcinoma (GA) tissues by immunohistochemistry assists in deciding whether targeted therapy would optimise the treatment of GA patients who are HER2 positive. However, this has not been extensively studied in our patients hence the need for this study.Recipient tissue microarray blocks were constructed from donor archival formalin fixed paraffin embedded gastric tumour tissue from 80 patients seen over a period of 17 years in a retrospective descriptive study. Slides cut from these blocks were stained with antihuman HER2 antibody by immunohistochemistry and scored using the trastuzumab in gastric adenocarcinomas (ToGA) trial criteria. Data on age, gender, site of lesion and histological subtype of the gastric adenocarcinomas were also retrieved and reviewed.Eighty cases (52 males and 28 females; male to female ratio of 1.9:1), 55.65 ±13.50 years (modal age group 60-69 years), were studied. Most tumours (91.2%) involved the distal parts (pylorus, antrum and body) with a few (8.8%) involving the proximal part (cardia and fundus) of the stomach. HER2 was overexpressed in a total of 6 (7.5%) cases only. Two of seven (28.6%) proximal tumours showed HER2 positivity whereas only 4 of 73 (5.5%) of the distal tumours showed HER2 positivity.We had only a slightly lower HER2 overexpression rate than in studies from many other parts of the world. The observed overexpression was significantly higher in proximal than distally located tumours suggesting that distal tumours are less likely to respond to Trastuzumab than proximal tumours. The known association of distal gastric tumours with Helicobacter pylori infection probably provides for a possible difference in the molecular aetiopathogenesis of GAs by site of occurrence. The exact mechanisms for proximal gastric carcinogenesis remain to be more clearly elucidated. More studies, including clinical trials with larger sample sizes, are recommended to elucidate this differential expression of HER2 in gastric adenocarcinoma.Copyright © 2024 by West African Journal of Medicine.