title: Rate of progression to advanced stage in depressed-type colorectal adenoma.
abstract: To better estimate the likelihood of depressed-type adenoma developing into more advanced colorectal cancer, we assumed that a given colorectal cancer had a depressed type origin when depressed non-polypoid-type cancerous glands remained microscopically identifiable. Among 100 adenomas, depressed non-polypoid-type glands were found in 15, and lesion size in tumor with depressed non-polypoid type did not differ from that in others. Among 100 submucosally invasive cancers, depressed non-polypoid-type glands were found in 14, and lesion size in tumor with depressed non-polypoid-type did not differ from that in others. Among 100 cancers invading the muscularis propria, depressed non-polypoid-type glands were found in 15; these were significantly smaller lesions than those without depressed non-polypoid-type cancers (p<0.05). Among 100 more deeply invasive cancers, depressed non-polypoid-type grands were found in 16, with no difference in size from other similarly invasive lesions. We concluded that the rate of depressed-type adenoma progression to invasive cancer was about 15% and that depressed non-polypoid-type cancers are likely to invade the muscularis propria even when smaller than cancers of other types.
authors.affiliation: First Department of Internal Medicine, Gunma University School of Medicine, Maebashi-shi, Gunma 371-8511, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Saito
authors.forename: M
authors.initials: M
authors.lastname: Mori
mesh_terms: D000236:Adenoma / Q000145:classification / Q000473:pathology* / Q000601:surgery; D003111:Colonic Polyps / Q000473:pathology* / Q000601:surgery; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D018450:Disease Progression; D006801:Humans; D007417:Intestinal Polyps / Q000473:pathology* / Q000601:surgery; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012189:Retrospective Studies; D013997:Time Factors