Screening for colonic neoplastic lesions using flexible sigmoidoscopy in employees of a nuclear research center and members of collective settlements.

It has been shown that screening of average risk individuals reduces the incidence of colorectal cancer. The most effective method for screening has yet to be determined in terms of cost-effectiveness, but approximately two-thirds of colorectal neoplastic lesions are within the reach of the flexible sigmoidoscope. It has been estimated that a single such examination at the end of the sixth decade may reduce the colorectal cancer incidence by 60%. As part of a screening program for colon cancer, short colonoscopy was performed on 399 employees of a nuclear research center and 228 members of a collective settlement (kibbutz). The examinations were carried out on individuals aged > or = 40 years by two experienced endoscopists. The splenic flexure or transverse colon was reached in 95% of the procedures. Neoplastic lesions were found in 24 (6.0%) and 8 (3.5%) screenees (not significant) in the Nuclear Research Center and kibbutz populations respectively. Polyps <1 cm in diameter were significantly more common in the Nuclear Research Center population but larger polyps and cancers were not. In 47 Nuclear Research Center screenees with a family history positive in a first-degree relative, findings increased to 14.9% (P = 0.016). A family history of malignancy was found in 33.8% of kibbutz members but in only 11.8% of Nuclear Research Center employees. There was no evidence to suggest that working at the Nuclear Research Center increased the risk of colonic neoplasms. We conclude that flexible sigmoidoscopy is a valuable screening tool, especially for individuals with a first-degree relative with cancer. The yield of neoplastic lesions in the Israeli Nuclear Research Center and kibbutz populations is similar to that of the general population in the western world. Compliance rates are high in well-defined populations.