Longitudinal study of bladder cancer with cytology and biopsy.

A study of urinary cytology and selected mucosal biopsies in conjunction with cystoscopy provided additional information of value in the management of 318 patients with bladder cancer. These procedures were especially helpful in patients with no visible lesions on follow-up cystoscopies in assessing the bladder epithelium, the behaviour of which may be unpredictable in that no further tumours may occur, or they may arise at irregular intervals.