[Characteristics of colorectal carcinomas detected by mass screening]

In order to evaluate effectiveness of mass screening for the detection of a colorectal carcinoma, 60 patients with a colorectal carcinoma that had been detected by fecal occult blood tests (mass screened group) were compared to 119 patients who were voluntarily diagnosed at an out-patient clinic (control group), and the following results were obtained. The site of carcinoma as being at the rectum in the mass screened group was rarely initially detected when compared to the control group. The frequency of an early stage carcinoma was 53.3% in the mass group and 17.6% in the control group. Twenty-three of the 60 patients in the mass group received an endoscopic polypectomy, and 8 patients of these also were surgically treated for a bowel resection. Curative treatment was performed on 91.8% of the patients in the mass group and 81.5% in the control group. These results indicate that the mass screening using the fecal occult blood test is effective for a reduction in the mortality rate from colorectal carcinoma.