Katsuji Takemura

Higher frequency of point mutations in the c-K-ras 2 gene in human colorectal adenomas with severe atypia than in carcinomas

Human colorectal carcinomas may be induced from adenomas or they may occur de novo. To examine which is the main pathway, we analyzed point mutations at codon 12 in the c‐K‐ras 2 gene in 73 colorectal carcinomas, 13 metastatic tumors, 72 adenomas and 30 normal tissues. The c‐K‐ras 2 codon 12 mutation frequency was 0/30 in normal tissues, 0/17 in adenomas with mild atypia, 3/37 (8.1%) in adenomas with moderate atypia, 15/18 (83.3%) in adenomas with severe atypia, 19/73 (26.0%) in primary carcinomas and 3/13 (23.1%) in metastatic tumors. The mutation frequency in adenomas with severe atypia was much higher than that in carcinomas. These results indicate that many colorectal carcinomas may not be induced through adenomas with severe atypia.

Mutations in c-K-ras 2 gene codon 12 during colorectal tumorigenesis in familial adenomatous polyposis

Colorectal carcinomas may be induced from adenomas, or they may occur de novo. To clarify the histogenesis of colorectal carcinomas, point mutations in codon 12 of the c-K-ras 2 gene in neoplasias of familial adenomatous polyposis patients were examined. Nineteen colorectal advanced carcinomas, 135 adenomatous polyps, 9 hyperplastic polyps, and 27 normal colonic mucosae were obtained from 48 patients. In 27 normal mucosae and 9 hyperplastic polyps, a mutation in the K-ras gene was not detected. Mutations were detected as follows: 0 of 24 in adenomas with mild atypia, 10 of 77 in adenomas with moderate atypia, and 24 of 34 in adenomas with severe atypia. The incidence of mutations in c-K-ras 2 codon 12 is correlated with the degree of atypia of adenomas. However, only 5 such mutations were detected in 19 advanced carcinomas, indicating that the mutation frequency in advanced carcinomas is much lower than that in adenomas with severe atypia. If a mutation of c-K-ras 2 gene is an important component in the formation of adenocarcinoma, these results did not confirm the successive development from adenomas with severe atypia to advanced carcinomas as the main route for colorectal carcinogenesis in familial adenomatous polyposis patients.

The Peutz-Jeghers Syndrome and Malignant Tumor

In our 19 cases of the Peutz-Jeghers (P-J) syndrome, we experienced two cases of carcinoma of the small intestine and two cases of uterine carcinoma. In 420 reported cases the of the P-J syndrome in Japanese literature there were 70 cases of gastrointestinal carcinoma ( mean age of 34.4 years) and 21 cases of extra gastrointestinal cancer (mean age of 41.2 years). Mucus producing adenocarcinoma was common patho-histological subdivision of gastrointestinal carcinoma (39%). Twelve of 20 cases of extra gastrointestinal cancer were uterine (9 cases) or ovarial (2 cases) carcinoma. Cervical adenocarcinoma (6 cases) was thought to be a specific cancer associated with the P-J syndrome.

Sclerotherapy of internal hemorrhoids using newly devised transparent disposable anorectoscope

SummaryWe devised a transparent anorectoscope for internal hemorrhoidal sclerotherapy. Using this scope the grade of hemorrhoids of the patients can be evaluated accurately through the transparent wall of the scope, and the device facilitates easier and safer sclerotherapy under clear direct vision, compared to the conventional free-hand-style treatment. We conclude that sclerotherapy using this anorectoscope represents a minimally invasive treatment for low-grade internal hemorrhoids and is recommendable for outpatient therapy of internal hemorrhoids.

A Comparative Study on Retrospective Evaluation of the Prognosis of the Colorectal Calcinomas Using New TNM and General Classifications.

昭和49年から62年までに切除された大腸癌258例を対象に, 1987年に改定された新TNM分類と現行の大腸癌取扱い規約の2つの分類に沿ってretrospectiveに病期分類を行い.2つの分類法の特徴について検討した.その結果, 新TNM分類による生存率曲線は比較的バランスのよい形を保って下降していた.亜分類された各深達度の5生率には余り差がなく, pN1, pN2, 3の間の5生率には統計学的有道差が得られた.規約分類による生存率曲線ではstage III, IVの曲線が近接していた.またsinomoの5生率は85.7%と良好でn1とn2の5生率は52.3%, 64.1%と逆転していた.Dukes分類に準じた新TNM分類は大腸癌の予後を良く反映していたが, リンパ節の転移度は病期に反映させるべきであろうと思われた.規約分類のstage III, IVの分類法には臨床的限界があり, 特にリンパ節の分類法は再検討されるべきであった.