22例微卫星DNA不稳定性大肠癌家系筛查结果分析

目的通过对既往已确认有微卫星不稳定的大肠癌患者的一级亲属随访调查研究，筛查遗传性非息肉病型大肠癌家系及早期遗传性非息肉病型大肠癌。方法选取已确认发现微卫星不稳定性（MSI）阳性大肠癌患者的一级亲属66例，进行随访。对尚未发生恶性肿瘤的63例无症状筛查对象行电子大肠镜检查，病变组织取病理活检，组织行HE染色，经病理医师诊断。结果66例筛选对象中已有3例发生恶性肿瘤，其他63例筛查对象中肠镜检查发现结肠绒毛状腺瘤1例，大肠息肉7例，遵循Amsterdam标准Ⅱ确诊4个HNPCC家系，其中结肠腺瘤病例出现在HNPCC家系中，属于癌前病变。结论具有遗传背景的MSI阳性的大肠癌患者的一级亲属有可能是遗传性非息肉性大肠癌的高危人群。对这些高危人群应进行定期的随访观察，有望早期发现HNPCC家系和早期遗传性非息肉病型大肠癌患者。

The Screening for Colorectal Cancer Family with MSI: A Clinical Analysis of 22 Cases

Objective To estimate the clinical value of MSI detection in the screening of HNPCC patient and patients in the case which with familial predisposition and comfirmed as MSI by the progress of PCR-SSCP. Methods We followed up 21 MSI positive CRC patients＇ families which was with familial predisposition by 5 years,and applied colonoscope to screen the CRC patients in the 63 primary relatives.The tissue abtained from colonoscope were diagnose by sheet HE staining. Results Of the 66 cases,three cases were occurred HNPCC associated cancer between 2003 and 2009, one（1/66） was colon cancer,one（1/66） was rectal cancer,one was endometrial cancer. In the remain 63 cases, one（1/66（1/66） was final diagnosed as in situ colon carcinoma,another seven（7/66）cases were diagnosed colorectal polypi,4 famihes were classified as HNPCC family. Conclusion Direct relatives of MSI positive CRC patients are high-risk population of HNPCC. Follow up the high-risk population may find the earlier colorectal cancer.