Leukoplakia of the urinary tract: a review.

We herein describe 44 new cases of leukoplakia of the renal pelvis, bladder and urethra. Leukoplakia is uncommon. It occurs twice as often in the bladder as in the pelvis and ureter and it is associated with and perhaps caused by chronic infection. Carcinoma is present in 10 to 20 per cent of the cases at diagnosis. We believe that leukoplakia is not simple squamous metaplasia but a step further down the line--a process that evolved through squamous metaplasia and perhaps could result in cancer. We think leukoplakia is potentially pre-malignant and it should be treated as a low grade and low stage tumor since no satisfactory treatment exists.