Obstetrical & Gynecological Survey · 2005 · 18 citations · 0 references
MedicineClinical SciencesOncologyCancer ScreeningGastroenterologyGastrointestinal OncologyCancer SurveillanceColonic DiseasesColorectal CancerGastrointestinal EndoscopyScreeningTumor SurveillanceColonoscopy ScreeningColorectal Cancer DiagnosisColorectal Cancer PreventionColorectal Cancer ScreeningEndoscopic ScreeningSurveillance ColonoscopySurveillance Endoscopy
Colonoscopic screening detects advanced colorectal neoplasia that flexible sigmoidoscopy would miss, as shown by the VA Cooperative Study 380. The study aimed to assess the yield of screening colonoscopy in asymptomatic women by offering colonoscopy to consecutive referrals. Researchers calculated the diagnostic yield of flexible sigmoidoscopy by estimating which advanced lesions would be detected if only sigmoidoscopy were performed, defining detectability as distal colon lesions or proximal lesions with concurrent distal adenomas. Among 1,463 women, colonoscopy identified advanced neoplasia in 4.9% (72/1463), whereas flexible sigmoidoscopy would have detected only 35.2% of these cases (1.7% overall), indicating colonoscopy is the preferred screening method for women.
Veterans Affairs (VA) Cooperative Study 380 showed that some advanced colorectal neoplasias (i.e., adenomas at least 1 cm in diameter, villous adenomas, adenomas with high-grade dysplasia, or cancer) in men would be missed with the use of flexible sigmoidoscopy but detected by colonoscopy. In a tandem study, we examined the yield of screening colonoscopy in women.To determine the prevalence and location of advanced neoplasia, we offered colonoscopy to consecutive asymptomatic women referred for colon-cancer screening. The diagnostic yield of flexible sigmoidoscopy was calculated by estimating the proportion of patients with advanced neoplasia whose lesions would have been identified if they had undergone flexible sigmoidoscopy alone. Lesions were considered detectable by flexible sigmoidoscopy if they were in the distal colon or if they were in the proximal colon in patients who had concurrent small adenomas in the distal colon, a finding that would have led to colonoscopy. The results were compared with the results from VA Cooperative Study 380 for age-matched men and women with negative fecal occult-blood tests and no family history of colon cancer.Colonoscopy was complete in 1463 women, 230 of whom (15.7 percent) had a family history of colon cancer. Colonoscopy revealed advanced neoplasia in 72 women (4.9 percent). If flexible sigmoidoscopy alone had been performed, advanced neoplasia would have been detected in 1.7 percent of these women (25 of 1463) and missed in 3.2 percent (47 of 1463). Only 35.2 percent of women with advanced neoplasia would have had their lesions identified if they had undergone flexible sigmoidoscopy alone, as compared with 66.3 percent of matched men from VA Cooperative Study 380 (P<0.001).Colonoscopy may be the preferred method of screening for colorectal cancer in women.