[Conservative endoscopic treatment of urothelial cystic dysplasia of the upper urinary tract].

We highlight the importance of the new diagnostic possibilities afforded by ureterorenoscopy and nephroscopy in the differential diagnosis of single or multiple cystic dysplasia of the upper excretory tract. Moreover, endoscopic treatment was performed in the two cases reported herein. In the first case the biopsy procedure was also therapeutic and in the second case cyst removal resolved the ureteral obstruction. Because the disease is detected infrequently and because treatment may be required even less frequently, several technical solutions have been applied to assess efficacy and reliability. Diathermy coagulation has proved to be the safest, fastest and the most effective. Follow-up has documented the absence of recurrence and good reepithelialization of the ureteral wall without progression to stricture. In those cases with single cyst, one-stage diathermy loop resection permits obtaining biopsy material and radical removal of the neoformation.