Bladder Washing Cytology for Detection of Urothelial Carcinoma Using Catheter or Flexible Cystoscope: Which is Better? A Prospective Randomized Study

Urine cytology can be collected with spontaneous urine or by washing the bladder. It is commonly accepted among urologist that instrumental bladder washing is the method of choice. There are, however, no solid recommendations regarding the method to collect the urine for bladder wash cytology during cystoscopy. There are mainly two possibilities: 1) the use of an intermittent bladder catheter after the removal of the cystoscope or 2) bladder lavage through working channel of the flexible cystoscope itself. The first choice may increase the number of collected cells because of the larger caliber of the catheter compared to the working channel and thus the better efficacy of bladder wash. However, this method is certainly more invasive and possibly more expensive. To the best of our knowledge and according to available literature, none of both collection method can be defined as gold standard. The aim of the study is to show that use of flexible cystoscope brings the same results in terms of quality of the urine collection for analysis as the use of intermittent bladder catheter and is less unpleasant for the patient. If our study confirms the non-inferiority of "direct" collection through the cystoscope, this will allow the establishment of recommendations in this sense in order to simplify the procedure and reduce as much as possible the manipulations within the urogenital tract.