BACKGROUND/AIMS: It has been uncertain whether colorectal carcinomas preferentially arise on preexisting adenomas or de novo. However, from a morphological viewpoint, it seems unlikely that pedunculated or exophytic malignant polyps progress to the deeply ulcerated advanced carcinomas usually found clinically. METHODS: The morphological features of 26 nonpolypoid, superficial-type colorectal tumors (17 adenomas and 9 adenocarcinomas) were compared to clarify the developmental route of colorectal carcinomas. RESULTS: The adenomas and adenocarcinomas were very similar in size and gross appearance; however, examination of the surface appearances of unsectioned tumors by dissecting microscopy was helpful for distinguishing the two. Histologically, no adenomatous tissue was found in any case of superficial-type adenocarcinoma. Five of the nine adenocarcinomas, even including those of small size, invaded the submucosal layer, and two showed lymph node metastasis. CONCLUSIONS: These findings suggest that superficial-type adenocarcinomas show rapid growth and aggressive behavior. We suggest that this type of carcinoma may not progress by the adenoma-to-carcinoma pathway but that it may arise from a very small superficial-type adenoma.
BACKGROUND/AIMS: It has been uncertain whether colorectal carcinomas preferentially arise on preexisting adenomas or de novo. However, from a morphological viewpoint, it seems unlikely that pedunculated or exophytic malignant polyps progress to the deeply ulcerated advanced carcinomas usually found clinically. METHODS: The morphological features of 26 nonpolypoid, superficial-type colorectal tumors (17 adenomas and 9 adenocarcinomas) were compared to clarify the developmental route of colorectal carcinomas. RESULTS: The adenomas and adenocarcinomas were very similar in size and gross appearance; however, examination of the surface appearances of unsectioned tumors by dissecting microscopy was helpful for distinguishing the two. Histologically, no adenomatous tissue was found in any case of superficial-type adenocarcinoma. Five of the nine adenocarcinomas, even including those of small size, invaded the submucosal layer, and two showed lymph node metastasis. CONCLUSIONS: These findings suggest that superficial-type adenocarcinomas show rapid growth and aggressive behavior. We suggest that this type of carcinoma may not progress by the adenoma-to-carcinoma pathway but that it may arise from a very small superficial-type adenoma.
Authors: J Rüschoff; W Dietmaier; J Lüttges; G Seitz; T Bocker; H Zirngibl; J Schlegel; H K Schackert; K W Jauch; F Hofstaedter Journal: Am J Pathol Date: 1997-05 Impact factor: 4.307
Authors: Hiroki Yuhara; Craig Steinmaus; Stephanie E Cohen; Douglas A Corley; Yoshihiro Tei; Patricia A Buffler Journal: Am J Gastroenterol Date: 2011-09-13 Impact factor: 10.864
Authors: K Konishi; M Takimoto; K Kaneko; R Makino; Y Hirayama; H Nozawa; T Kurahashi; Y Kumekawa; T Yamamoto; H Ito; N Yoshikawa; M Kusano; K Nakayama; B J Rembacken; H Ota; M Imawari Journal: Br J Cancer Date: 2006-01-30 Impact factor: 7.640
Authors: K Kaneko; T Kurahashi; R Makino; K Konishi; H Ito; A Katagiri; Y Kumekawa; Y Hirayama; K Yoneyama; M Kushima; M Kusano; H Tajiri; B J Rembacken; K Mitamura; M Imawari Journal: Br J Cancer Date: 2004-07-19 Impact factor: 7.640