Cytologic detection of urothelial cancer and other abnormalities in a cohort of workers exposed to aromatic amines.

A total of 541 members of a cohort at increased risk for occupational bladder cancer underwent a 33-month program of screening with urine cytology. Selected workers received further urologic study with cystoscopy and bladder biopsies. Eight workers had positive or suspicious cytologic findings. Only one of the eight had a prior history of bladder cancer. Biopsies showed invasive carcinoma and/or nonpapillary carcinoma in situ in five workers in this group, severe atypia in one, and no significant abnormality in two. Of 56 workers who had atypical cytologic findings, 16 had bladder biopsies, which showed atypia of flat urothelium in 11, nonpapillary carcinoma in situ in one, noninfiltrating papillary carcinoma in one, and no significant abnormality in three. The cytologic detection of urothelial abnormalities often required more than a single specimen. Since the cohort in this study may develop more bladder cancers with the passage of time, continued follow-up is indicated.