Risk of Colorectal Adenoma and Carcinoma After Colectomy for Colorectal Cancer in Patients Meeting Amsterdam Criteria

Abstract

To report the risk of metachronous colorectal neoplasia after colectomy for cancer in Hereditary Nonpolyposis Colorectal Cancer (HNPCC) syndrome. Patients meeting Amsterdam criteria for diagnosis of HNPCC have a lifetime colorectal cancer risk approaching 80%, and a metachronous cancer rate of approximately 25%. Therefore, when colon cancer is diagnosed, total rather than segmental colectomy is advocated. However, information about adenoma and carcinoma risk after index surgery is still underreported. A hereditary colorectal cancer database was reviewed for patients meeting Amsterdam criteria who underwent colectomy for cancer. Patient demographics, surgical management, and results of follow-up were recorded. Metachronous colorectal adenoma and carcinoma development were the primary end points. A total of 296 patients (253 with segmental colectomy and 43 with total colectomy/ileorectal anastomosis) were analyzed. Of the 253 segmental colectomy patients, 221 (88%) had postoperative endoscopic surveillance with median follow-up of 104 months. In 74 patients (33%), 256 adenomas were detected, including 140 high-risk adenomas in 48 patients (22%). Fifty-five patients (25%) developed a second colorectal cancer at a median of 69 months after index surgery. Stages of the metachronous cancers were I-16, II-18, III-12, and IV-2. By comparison, 4 of 38 patients (11%) who underwent total colectomy developed subsequent high-risk adenomas and 3 (8%) developed metachronous cancer. Amsterdam patients undergoing partial colectomy have a high rate of metachronous high-risk adenomas and carcinomas. Total colectomy for the index cancer is the procedure of choice. For either surgical option, yearly endoscopic surveillance is essential to remove premalignant adenomas.