Histopathological Diagnosis of the Colorectal Villous Tumor Teruyuki Hirota 1 , Kiyoshi Hanashiro 1 , Masayuki Itabashi 1 1Pathology Division, National Cancer Center Research Institute pp.1295-1302
Published Date 1986/12/25
DOI https://doi.org/10.11477/mf.1403110056
  • Abstract
  • Look Inside

 The incidence of the colorectal carcinoma, especially carcinoma in the sigmoid colon has been increasing in Japan recently. Needless to say, adenoma is considered to be an important precancerous lesion of the colorectal carcinoma. In this paper, the relationship between adenoma and carcinoma was described based on our materials experienced.

 The frequency of the villous tumor was 3.6%, i.e., only four villous tumors found among 111 polyps resected surgically, during the period from 1962 to the end of 1975. However, among 483 polypectomized lesions during the period from 1962 to 1985 in our hospital, the villous tumor was noted in only three lesions (0.6%). Villous tumor was more frequently seen in the older age group than in the younger age group. It occurred most frequently in the recto-sigmoid region. A macroscopic feature typical to the surgically resected villous tumor was broad-based elevation in shape. Histological examination revealed numerous delicate vertical or radiated linear projection of the neoplastic epithelium from the fibrous core or lamina muscularis mucosae.

 Tubulo-villous adenoma, a mixed lesion of tubular and villous adenomas, was seen in 163 (33.8%) out of 483 polypectomized lesions. The coincidence rate of carcinoma in tubulo-villous adenoma was relatively high (34.4%). On the other hand, the incidence rate of carcinoma occurring in the typical villous tumor was low, i.e., 8 (4.5%) out of 177 lesions experienced in our hospital during the same period. Again the coincidence rate of tubulo-villous adenoma with carcinoma was high, i.e., 47.5% of the same series of lesions.

 These findings lead to the speculation that tubulo-villous adenoma is more important as a precancerous lesion than villous adenoma.

Copyright © 1986, Igaku-Shoin Ltd. All rights reserved.


電子版ISSN 1882-1219 印刷版ISSN 0536-2180 医学書院