Outtaleb F Z, Alami A, Serbati N, Benchakroun N, Bouchbika Z, Jouhadi H, Tawfiq N, Sahraoui S, Benider A, Dehbi H
Laboratory of Medical Genetics, Ibn Rochd University Hospital of Casablanca, Morocco.
Mohamed VI Oncology Center, Ibn Rochd University Hospital of Casablanca, Morocco.
Ann Med Surg (Lond). 2021 Jan 17;62:123-126. doi: 10.1016/j.amsu.2021.01.017. eCollection 2021 Feb.
Colorectal cancer is a major global health problem. In 5% of cases, a genetic predisposition to cancer's syndrome is the etiology, such as Lynch syndrome. The population prevalence of Lynch syndrome has been estimated at 1/440. The objectives of this study are to show the interest of the oncogenetic consultation in the management of patients with suspicion of Lynch syndrome.
It is a 70-year-old patient with a family history of different neoplasms. The patient has also been followed for an adenocarcinoma of the colon. An oncogenetic consultation was indicated, which led to the diagnosis of Lynch syndrome, according to the Amsterdam II criteria. A study of the MisMatch Repair genes was requested, to allow a pre-symptomatic diagnosis of apparented subjects at risk, and thus to also allow monitoring and early diagnosis of neoplasms or prophylactic measures.
Lynch syndrome is one of the most common cancer susceptibility syndromes. A constitutional deleterious mutation in one of the DNA MisMatch Repair genes, is responsible for nearly 70% of cases of this syndrome. The oncogenetic consultation and the identification of the genetics cause, makes it possible to set up specific monitoring and to offer a pre-symptomatic test to all major relatives of the index case.
This medical observation shows the benefit of the oncogenetic consultation, if a genetic predisposition to cancer's syndrome is suspected. The diagnostic of this predisposition and monitoring of the propositus and his exposed, like in Lynch syndrome will help in the early management of cancers, specially colorectal cancer and endometrial adenocarcinoma.
结直肠癌是一个重大的全球健康问题。在5%的病例中，癌症综合征的遗传易感性是病因，如林奇综合征。林奇综合征的人群患病率估计为1/440。本研究的目的是展示肿瘤遗传学咨询在疑似林奇综合征患者管理中的作用。
这是一名70岁的患者，有不同肿瘤的家族史。该患者还因结肠癌接受随访。根据阿姆斯特丹II标准，进行了肿瘤遗传学咨询，结果诊断为林奇综合征。要求对错配修复基因进行研究，以便对有风险的亲属进行症状前诊断，从而也能对肿瘤进行监测和早期诊断或采取预防措施。
林奇综合征是最常见的癌症易感性综合征之一。DNA错配修复基因之一的遗传性有害突变导致了该综合征近70%的病例。肿瘤遗传学咨询和遗传病因的确定，使得能够建立特定的监测，并为索引病例的所有主要亲属提供症状前检测。
本医学观察表明，如果怀疑有癌症综合征的遗传易感性，肿瘤遗传学咨询是有益的。对这种易感性的诊断以及对先证者及其亲属（如林奇综合征患者）的监测将有助于癌症的早期管理，特别是结直肠癌和子宫内膜腺癌。
