Between November 1991 and June 1993, 315 patients with urethral lesions were divided into two groups: group 1 included 215 patients with urethral tumours and group 2 included 100 patients with non-tumoural lesions. In all patients, urethral smears (performed on 3 consecutive days), pyelography and uretrocystoscopy (with bladder biopsy of observable lesions) were performed in all. The sensitivity of urine cytology examinations in the diagnosis of bladder cancer was found to by 80% with a specificity of 90%. The positive predictive value was 94.5% and the negative predictive value 67.7%. Urine cytology agreed with the diagnosis of urethral tumours especially well in advanced stage ulcerated tumours. These results underline the importance of cytology examinations in the exploration and follow-up of patients with urethral tumours.