Multiple mucosal biopsies and postoperative urinary cytology in patients with bladder cancer.

Seventy-one patients with bladder tumors of stage Ta, T1 or T2 were studied by bladder mucosal biopsies. In 34 (48%) patients abnormal histology was found in at least one of the biopsies. The occurrence and severity of mucosal abnormalities were related to tumor grade and stage. Urinary cytology after complete tumor resection was positive in 18 of 19 patients with abnormal biopsies and in 6 of 12 patients with normal biopsies. Postoperative urinary cytology seems to be a good indicator for the presence of urothelial atypia.