Abstract

A histopathologic study was made on 186 cases of rectal tumors of the Koreans, obtained during a period of 11 years, from 1957 to 1967, at the department of pathology, college of medicine, Seoul National University. 1. The 186 cases of rectal tumors consist of 145 cases of malignant tumors and 41 cases of benign tumors. 2. The malignant and benign tumors occurs more commonly in male than in female, revealing the sex ratio of 2.01: 1 in the malignant and 4.7: 1 in the benign respectively. 3. The age distribution of the rectal tumors varies from 13 to 78 years in malignant tumors and 6 to 71 in benign. The greatest number of rectal carcinomas occurred from 40 to 69 with a peak incidence in 50-59 years, revealing 31.6 per cent of total malignancies of the rectum. 4. The site of distribution of rectal carcinomas are as follows; 71% in the lower one third, 18% in mid one third and 11% in upper one third. In benign tumors, the distributions are similar to that of the malignant, showing the lower one third 50% mid one third 29.1% upper one third 8.33% and entire rectum 12.5%. 5. The gross pattern of the carcinomas are classified into three types, the polypoid type 53.8%, infiltrating 26.2%, and annular 20%. 6. Six cases of polypoid adenoma and a hereditary multiple polyposis were combined with focal malignant changes, which was 17.1% of total benign tumors. 7. The 145 cases of malignant and 41 cases of benign tumors of the rectum were histologically classified and tabulated.