Cytologic detection of bladder cancer in a rural Egyptian population infected with schistosomiasis.

A study was initiated in September 1976 to detect early bladder carcinoma by selective cytologic screening in a rural Egyptian population infested with Schistosoma haematobium. All persons in a high-risk group, i.e., farmers aged 20 years and above, and selected persons from two low-risk groups were screened. Bladder carcinoma was detected in 11 patients among the 4,769 individuals screened in the high-risk group, for a yield of 2.3 per 1,000. No tumors were detected in the 3,975 individuals in the low-risk groups. Cytologically diagnosed tumors were verified by histology in all cases. One of the detected tumors in a female was found to be metastatic from carcinoma of the cervix. The primary tumors included five squamous cell carcinomas, four transitional cell carcinomas and one undifferentiated carcinoma. Seven of the tumors were at early stages, including three noninvasive (TIS) and four superficial (T1 and T2) ones. This investigation indicates that selective cytologic screening in the high-risk group in Egypt is feasible and effective for the early detection of bladder carcinoma associated with schistosomiasis.