Risk and cause of interval colorectal cancer after colonoscopic polypectomy.
BACKGROUND
To investigate the cause and risk of interval colorectal cancer (ICC) in patients undergoing surveillance colonoscopy within 5 years after colonoscopic polypectomy.


METHODS
We retrospectively analyzed data (endoscopy, pathology, demography) of patients who received surveillance colonoscopy within 5 years after colonoscopic polypectomy.


RESULTS
Among 1,794 patients undergoing surveillance colonoscopy within 5 years after colonoscopic polypectomy, 14 suffered from ICC. The mean follow-up time was 2.67 years and the incidence density of ICC was 2.9 cases per 1,000 person-years. 50% of ICCs were found in patients in whom adenomas had been incompletely removed by endoscopic therapy, 36% were missed cancers, and 14% were new cancers. Age >60 years (OR 2.97, 95% CI 2.31-3.82) was significantly associated with interval cancer on the surveillance colonoscopy as were advanced adenoma (OR 1.28, 95% CI 1.01-1.62), the presence of villous (HR 1.38, 95% CI 1.03-1.85) and high-grade dysplasia (OR 1.61, 95% CI 1.07-2.42).


CONCLUSIONS
Among patients undergoing surveillance colonoscopy within 5 years after polypectomy, the incidence density of ICC was 2.9 cases per 1,000 person-years. The majority of interval cancers originated from incomplete resection of advanced adenomas and missed cancers, which can be prevented by improving endoscopic techniques and selecting an appropriate follow-up time interval.
Department of Gastroenterology, Affiliated Hospital of Inner Mongolia Medical College, Huhhot, PR China.
Yinglong
Y
Huang
Wei
W
Gong
Bingzhong
B
Su
Fachao
F
Zhi
Side
S
Liu
Bo
B
Jiang
D000236:Adenoma / Q000175:diagnosis / Q000601:surgery*; D018253:Adenoma, Villous / Q000175:diagnosis / Q000601:surgery; D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D003111:Colonic Polyps / Q000175:diagnosis / Q000601:surgery*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D003951:Diagnostic Errors; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D019300:Medical Errors; D008875:Middle Aged; D011230:Precancerous Conditions / Q000175:diagnosis / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors