MING-JIUM SHIEHWang C.-Y.JAU-MIN WONG2020-02-272020-02-2719981016-2372https://www.scopus.com/inward/record.uri?eid=2-s2.0-0032564931&partnerID=40&md5=68a4785ebff951e97f4241a6b933e613https://scholars.lib.ntu.edu.tw/handle/123456789/465841We conducted a prospective study to evaluate the diagnostic yield of primary colonoscopy in patients three or more years after curative resection for colorectal cancer (CRC). During a five-year period (1992-1996) 238 patients, (138 men and 100 women were enrolled and underwent complete colonoscopy. Of these, 230 patients had previous surgery and 8 patients had a polypectomy for malignant polyps. The mean age at presentation for colonoscopy was 62.0 years the mean duration between the first operation and screening colonoscopy was 84 months (range 36.10 489). Colonoscopic surveillance disclosed 6 cancers and 63 adenomas, giving a 29% diagnostic yield. Three cancer patients were found to have distant metastasis and had palliative treatment only. Five cases of small flat adenoma (Muto type) were detected of which two (40%) had malignant transformation. This finding suggests that adenomas found in patients with a history of CRC surgery may progress to cancer at a different rate from those in average-risk people who have not had a previous CRC. In conclusion, although primary colonoscopic screening for CRC after resection can give a relatively high diagnostic yield for colonic neoplasms, the rate of curative resection for metachronous CRC was only 50%. We recommend its use for follow-up of high-risk patients, but further studies are needed to establish the optimum time intervals.We conducted a prospective study to evaluate the diagnostic yield of primary colonoscopy in patients three or more years after curative resection for colorectal cancer (CRC). During a five-year period (1992-1996), 238 patients (138 men and 100 women) were enrolled and underwent complete colonoscopy. Of these, 230 patients had previous surgery and 8 patients had a polypectomy for malignant polyps. The mean age at presentation for colonoscopy was 62.0 years. The mean duration between the first operation and screening colonoscopy was 84 months (range, 36 to 489). Colonoscopic surveillance disclosed 6 cancers and 63 adenomas, giving a 29% diagnostic yield. Three cancer patients were found to have distant metastasis and had palliative treatment only. Five cases of small flat adenoma (Muto type) were detected, of which two (40%) had malignant transformation. This finding suggests that adenomas found in patients with a history of CRC surgery may progress to cancer at a different rate from those in average-risk people who have not had a previous CRC. In conclusion, although primary colonoscopic screening for CRC after resection can give a relatively high diagnostic yield for colonic neoplasms, the rate of curative resection for metachronous CRC was only 50%. We recommend its use for follow-up of high-risk patients, but further studies are needed to establish the optimum time intervals.Colonoscopy; Colorectal cancer patient; Follow-up; Operation[SDGs]SDG3Diagnosis; Oncology; Surgery; Colonoscopic screening; Colorectal cancer patients; Medical imaging; adult; article; cancer recurrence; cancer screening; colonoscopy; colorectal cancer; controlled study; diagnostic value; female; high risk population; human; major clinical study; malejournal article2-s2.0-0032564931