Renal ultrasound as a surveillance method for ureteroenteric anastomotic stricture following radical cystectomy and urinary diversion.

OBJECTIVE

To evaluate the performance of short-term renal ultrasound (RUS) as a surveillance tool to detect ureteroenteric anastomotic strictures (UAS) following robot-assisted radical cystectomy (RARC) and extracorporeal urinary diversion (ECUD).

METHODS

Patients with bladder cancer who underwent RARC and ECUD at a single tertiary center between October 2011 and August 2022 were included. All patients underwent a planned RUS at 6-weeks postoperatively. A radiologist and a urologist centrally reviewed all images to identify kidneys with hydronephrosis, which was diagnosed based on renal pelvis or calyceal dilation. Renal units with sonographic evidence of hydronephrosis underwent further confirmatory testing using fluoroscopic imaging (loopogram or pouchogram) and nuclear imaging (renal scan with Lasix washout). UAS was confirmed by placing a nephrostomy tube and an antegrade nephrostogram.

RESULTS

From a cohort of 392 patients who underwent RARC and ECUD, 316 were included. The median follow-up time was 36.8 months (IQR: 19.5, 78.8). A total of 623 renal units underwent 6-week RUS. Sonographic evidence of hydronephrosis was found in 23% (n = 143) of the units, of which 17% (n = 25) developed UAS. Of the 480 renal units without hydronephrosis, 0.2% (n = 1) developed UAS. 6-week RUS showed 96% and 80% sensitivity and specificity, respectively. The positive and negative predictive values were 17% and 99%, respectively.

CONCLUSIONS

A negative 6-week postoperative RUS can strongly predict the absence of UAS, making it a reliable, cost-effective, and non-invasive first-line screening modality to identify patients at a low risk of developing UAS after RARC and ECUD.