Pathology Department, Coimbra Hospital and University Centre.
Institute of Anatomical and Molecular Pathology, Faculty of Medicine, University of Coimbra.
Appl Immunohistochem Mol Morphol. 2024 Aug 1;32(7):350-356. doi: 10.1097/PAI.0000000000001212. Epub 2024 Aug 6.
Lynch syndrome (LS) is a prevalent genetic condition associated with colorectal cancer (CRC). Accurate identification of LS patients is challenging, and a universal tumor screening approach has been recommended. We present the methodology and results of universal LS screening in our hospital's Pathology Department. This retrospective study analyzed CRC tumors from a 5-year period (2017-2021). Immunohistochemistry was used to assess MMR protein expression, followed by BRAF V600E analysis and MLH1 promoter methylation. Statistical analysis examined associations between clinicopathologic variables MMR status and LS-suspected tumors. The study analyzed 939 colorectal carcinomas, with 8.7% exhibiting mismatch repair (MMR) deficiency, significantly lower than previous research. After applying the algorithm, 24 LS-suspected cases were identified, accounting for 2.6% of tested patients and 29.3% of MMR-deficient tumors. Our study establishes the feasibility of universal testing for all new cases of CRC in detecting individuals at risk for LS, even in the absence of clinical information. To gain a comprehensive understanding of the MMR status in our population, further investigations are warranted.
林奇综合征（LS）是一种与结直肠癌（CRC）相关的常见遗传疾病。准确识别 LS 患者具有挑战性，因此推荐了一种通用的肿瘤筛查方法。我们在医院病理科介绍了通用 LS 筛查的方法和结果。这项回顾性研究分析了 5 年内（2017-2021 年）的 CRC 肿瘤。免疫组织化学用于评估 MMR 蛋白表达，随后进行 BRAF V600E 分析和 MLH1 启动子甲基化分析。统计分析检查了 MMR 状态与 LS 疑似肿瘤之间的临床病理变量之间的关联。该研究分析了 939 例结直肠癌，其中 8.7%表现出错配修复（MMR）缺陷，明显低于先前的研究。应用该算法后，确定了 24 例 LS 疑似病例，占所有测试患者的 2.6%，占 MMR 缺陷肿瘤的 29.3%。我们的研究证实了对所有新的 CRC 病例进行通用检测以检测 LS 风险个体的可行性，即使在没有临床信息的情况下也是如此。为了全面了解我们人群中的 MMR 状态，需要进一步的研究。
