Peer-review started: April 9, 2020
First decision: June 7, 2020
Revised: July 16, 2020
Accepted: August 15, 2020
Article in press: August 15, 2020
Published online: September 12, 2020
Processing time: 152 Days and 14.3 Hours
Ureteral stent and nephroureterostomy tube (NUT) are treatments of ureteral obstruction. Ureteral stent provides better quality of life. Internalization of NUT is desired whenever possible.
To assess outcomes of capping trial among cancer patients with complete aspiration of retained contrast from bladder via NUT.
Our Institutional Review Board approved retrospective review of all NUT placement, NUT exchange and conversion of nephrostomy catheter into NUT performed during June 2013 to June 2015 (n = 578). Cases were excluded due to lack of imaging of bladder (n = 37), incomplete aspiration of bladder (n = 324), no attempt at capping NUT (n = 166), and patients with confounding factors interfering with results of capping trial including non-compliant bladder, bladder outlet obstruction and catheter malposition (n = 14). Study group consisted of 37 procedures in 34 patients (male 19, female 15, age 2-83 years, average 58, median 61) most with cancer (prostate 8, endometrial 5, bladder 4, colorectal 4, breast 2, gastric 2, neuroblastoma 2, cervical 1, ovarian 1, renal 1, sarcoma 1, urothelial 1 and testicular 1) and one with Crohn’s disease. Medical records were reviewed to assess outcomes of capping trial. Exact 95% confidence intervals (95%CI) were calculated.
Among patients with complete aspiration of retained contrast, 30 (81%, 95%CI: 0.65-0.92) catheters were successfully capped (range 12-94 d, average 40, median 24.5) until planned conversion to internal stent (23), routine exchange (5), removal (1) or death unrelated to catheter (1). Seven capping trials (19%, 95%CI: 0.08-0.35) were unsuccessful (range 2-22 d, average 12, median 10) due to leakage (3), elevated creatinine (2), fever/hematuria (1) and nausea/vomiting (1).
Capping trial success among patients with complete aspiration of retained contrast/urine from bladder via NUT appears high.
Core Tip: Patients with ureteral obstruction are best treated with cystoscopic placement of ureteral stent because of a better quality of life. When ureteral stent placement is not possible, a nephroureterostomy tube (NUT) is placed. Once the acute clinical problem is resolved, internalization is sought in order to improve patient’s quality of life. Currently all patients undergo NUT capping trial which is needed before internalization. This work helps urologists and interventional radiologists to estimate success of capping trial. It helps define the endpoint of NUT placement or exchange interventions with potential benefits to patients and health care systems.