Mathias-Machado Maria Cecilia, Peixoto Renata D, Ashton-Prolla Patricia, Da Silva Leonard Medeiros, Dienstmann Rodrigo
Oncolínicas Brasil, São Paulo, Brazil.
Department of Genetics of the Federal University of Rio Grande Do Sul, Porto Alegre, Brazil.
Case Rep Oncol. 2023 Jul 10;16(1):504-510. doi: 10.1159/000530965. eCollection 2023 Jan-Dec.
MUTYH-associated polyposis syndrome is an uncommon, autosomal recessive colorectal polyposis syndrome caused by biallelic inactivation of . Most patients present with multiple colorectal polyps. However, other primary tumor sites have been described as less frequent. In this report, we describe the case of a young patient with a germline biallelic pathogenic MUTYH mutation with three different primary tumors. We focused on a metastatic gastric adenocarcinoma that presented with complete bowel obstruction secondary to extensive peritoneal carcinomatosis and achieved complete response upon treatment with immunotherapy. The patient's tumor presented with a high tumor mutational burden and a 100% combined positive score, which certainly contributed to the complete response to immunotherapy. To date, no studies have described the association of -related tumors with high PD-L1 expression, but we hypothesized that it may be linked to the increased antigenicity of these cancers.
MUTYH相关息肉病综合征是一种罕见的常染色体隐性结直肠息肉病综合征，由biallelic失活引起。大多数患者表现为多发性结直肠息肉。然而，其他原发性肿瘤部位的报道较少见。在本报告中，我们描述了一名年轻患者，其携带种系biallelic致病性MUTYH突变，患有三种不同的原发性肿瘤。我们重点关注了一例转移性胃腺癌，该患者因广泛腹膜癌转移导致完全性肠梗阻，经免疫治疗后获得完全缓解。患者的肿瘤具有高肿瘤突变负荷和100%的联合阳性评分，这无疑促成了对免疫治疗的完全缓解。迄今为止，尚无研究描述与相关肿瘤与高PD-L1表达的关联，但我们推测这可能与这些癌症抗原性增加有关。
