Chan Renee Choy Foong, Katelaris Peter H, Stewart Peter, Lin Betty P C
Department of Anatomical Pathology, Concord Hospital, Concord NSW 2139, Australia.
Hum Pathol. 2006 May;37(5):631-4. doi: 10.1016/j.humpath.2005.12.013. Epub 2006 Mar 13.
Microsatellite instability (MSI) is a hallmark of carcinomas occurring in the setting of hereditary nonpolyposis colorectal cancer, but can also be found in sporadic and colitis-associated tumors. The incidence of MSI in Crohn's disease is unknown and has usually been reported in the colon. We report the case of a 26-year-old man, diagnosed 4 years earlier with Crohn's disease, who developed an associated small bowel adenocarcinoma. The tumor was found to have high levels of MSI by immunohistochemical staining and by MSI testing. No mutations were identified by genetic testing, and high levels of MSI are most probably due to hypermethylation.
微卫星不稳定性（MSI）是遗传性非息肉病性结直肠癌背景下发生的癌的一个标志，但也可在散发性和结肠炎相关肿瘤中发现。克罗恩病中MSI的发生率尚不清楚，通常报道于结肠。我们报告一例26岁男性病例，4年前被诊断为克罗恩病，随后发生了相关的小肠腺癌。通过免疫组织化学染色和MSI检测发现该肿瘤具有高水平的MSI。基因检测未发现突变，高水平的MSI很可能是由于高甲基化。
