Secondary foci of primary tumors of the bladder in the upper urinary tract.

In 10 years the authors have observed 16 cases of upper urinary tract tumors, appearing from 2 to 16 years after the initial diagnosis of bladder carcinoma. Such lesions are more frequent than has been suggested in the literature and represent 25% of all tumors of the renal pelvis and ureter seen in our service during this period. We have shown vesicoureteral reflux directly in 6 cases, indirectly in a further 6 with suggestive signs in 3 more. We believe that reflux causing the implantation of desquamated tumor cells from the bladder tumor is the most important pathogenetic mechanism for upper urinary tract "recurrences." The interval between the initial diagnosis of bladder tumor and the appearance of secondary foci may be longer than 20 years. Prolonged surveillance is therefore necessary, particularly if vesicoureteral reflux has been shown.