Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Urol. Sep 12, 2020; 9(1): 1-8
Published online Sep 12, 2020. doi: 10.5410/wjcu.v9.i1.1
Estimation of successful capping with complete aspiration of bladder via nephroureterostomy tube
Majid Maybody, Wesley K Shay, Deborah A Fleischer, Meier Hsu, Chaya Moskowitz
Majid Maybody, Wesley K Shay, Deborah A Fleischer, Department of Radiology, Interventional Radiology Service, Memorial Sloan Kettering Cancer Center, New York, NY 10065, United States
Meier Hsu, Chaya Moskowitz, Department of Biostatistics and Epidemiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, United States
Author contributions: Maybody M contributed to study conception and design, acquisition of data, analysis and interpretation of data, drafting of manuscript, and critical revision; Shay WK and Fleischer DA contributed to acquisition of data and critical revision; Hsu M and Moskowitz C contributed to analysis and interpretation of data, critical revision.
Supported by National Institute of Health (United States), No. P30 CA008748.
Institutional review board statement: This study was reviewed and approved by the Institutional Review Board/Privacy Board-B. The IRB determined that the protocol meets the requirements as set forth in the regulatory criteria for research approval and has been granted approval for 12 mo.
Informed consent statement: Your request to waive the requirement to obtain written informed consent and a research authorization has been granted.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Majid Maybody, MD, Associate Professor, Department of Radiology, Interventional Radiology Service, Memorial Sloan Kettering Cancer Center, No. 1275 York Avenue, M276C, New York, NY 10065, United States.
Received: April 9, 2020
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
Research background

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.

Research motivation

Before internalization of NUT patients should pass a capping trial. Currently there are no indicators of capping trial results.

Research objectives

To help urologists and interventional radiologists estimate successful capping trial during a NUT placement or exchange intervention. By preventing unsuccessful trials, patients and healthcare systems benefit.

Research methods

578 NUT placement, NUT exchange and conversion of nephrostomy catheter into NUT performed between 2013 and 2015 were reviewed. Exclusions were 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 (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 were calculated.

Research results

In 81% of study group (95% confidence intervals: 0.65-0.92) NUTs 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).

Research conclusions

The ability to aspirate retained contrast from bladder through NUT is an indicator for successful capping trial. If contrast cannot be aspirated form bladder through NUT, same session tube exchange (upsize or different length) should be considered.

Research perspectives

Prospective studies are required to further assess the findings of this study.