Diagnostic Value of Urine Cytology in Pharmacologically Forced Diuresis for Diagnosis and Follow-Up of Upper Tract Urothelial Carcinoma

We performed urine cytology analysis of a pharmacologically induced diuresis for diagnostics of upper tract urothelial carcinoma. To evaluate the diagnostic value of cytology of pharmacologically forced diuresis, a first cohort of 77 consecutive patients with primary upper tract urothelial carcinoma treated with radical surgery was enrolled. To evaluate pharmacologically forced diuresis cytology as follow-up procedure, a second cohort of 1250 patients who underwent radical cystectomy for bladder cancer was selected. In the first cohort, sensitivity of cytology of pharmacologically forced diuresis in patients with invasive, high-grade, low-grade, and concomitant carcinoma in situ was 8%, 9%, 0% and 14%, respectively. In the second cohort, cytology of pharmacologically forced diuresis was positive in 30/689 (4.3%) of patients, in whom upper urinary tract recurrence was present in 21/30 (70%) and urethral recurrence in 8/30 (26%) of cases. As a follow-up tool, cytology of pharmacologically forced diuresis showed a sensitivity, specificity, and positive and negative predictive value of 60%, 99%, 70% and 98%, respectively. Summarized, as diagnostic tool, sensitivity of cytology of pharmacologically forced diuresis is slightly better in patients with invasive upper tract urothelial carcinoma and concomitant carcinoma in situ. As follow-up method, positive cytology of pharmacologically forced diuresis is strongly related to cancer recurrence and can reveal urethral recurrence. cytology of pharmacologically forced diuresis might be useful in patients with contraindications for imaging or with difficult endoscopic access to the upper urinary tract.