title: The macroscopic appearance of colorectal polyps.
abstract: The macroscopic (10 to 30 times magnification) surface features of 187 colonic lesions are described. The lesions were studied using a dissecting microscope and a 1% trypan blue solution as a contrast agent. Using five criteria, lesions were evaluated for the presence or absence of adenoma, the type of adenoma present, the presence of dysplasia or carcinoma-in-situ, and the presence of invasive carcinoma. The technique has proven to be a rapid, sensitive, and relatively specific means of separating tumors in the adenoma--carcinoma sequence from nonadenomatous lesions (sensitivity, 99%, specificity 90%). The technique is accurate in differentiating tubular, tubulovillous, and villous lesions. It is suggested that areas of dysplasia (sensitivity 100%, specificity 93%), carcinoma-in-situ, and microinvasive carcinoma may also be differentiated, but need further investigation. The present study suggests that the macroscopic architecture of the various lesions in the adenoma--carcinoma sequence is unique and may be used diagnostically. These preliminary findings need to be confirmed in a prospective double-blind study, and to be adapted to use in colonoscopic and radiologic diagnosis.
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000473:pathology; D002277:Carcinoma / Q000175:diagnosis / Q000473:pathology; D002278:Carcinoma in Situ / Q000175:diagnosis / Q000473:pathology; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D007417:Intestinal Polyps / Q000175:diagnosis / Q000473:pathology*; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000473:pathology*