New System Classifies Male Anterior Urethral Stricture

By Will Boggs MD

July 29, 2020

NEW YORK (Reuters Health) - A newly developed and validated clinical system classifies male anterior urethral stricture disease based on length, segment/location, and etiology.

"This will aid in communication between surgeons," Dr. Bradley A. Erickson of the University of Iowa Carver College of Medicine, in Iowa City, told Reuters Health by email. "Eventually, this will aid in surgeons deciding on what type of repair should be used for a particular stricture (whereas now, an anterior urethra can be repaired in multiple different ways depending on location/length/etiology)."

Urethral stricture disease (USD) is a complex condition with a poorly understood pathophysiology that lacks a classification system.

Dr. Erickson and colleagues from the Trauma and Urologic Reconstruction Network of Surgeons (TURNS) sought to develop and validate a classification system for USD that would be easy to use, based on readily available clinical data, and objective enough to allow for high interrater reliability.

The variables they chose to include in the classification system included stricture length (L), stricture segment/location (S) and stricture etiology (E).

They further subdivided L into strictures less than 2 cm (L1), generally amenable to excision or repairs; strictures between 2 and 7 cm (L2), which can be repaired with a single substitution graft; and strictures greater than 7 cm (L3), which often require two sources of graft material or a fasciocutaneous tissue flap.

S was divided into bulbar (S1) and penile (S2) segments that were further subdivided depending upon which portions of those segments were involved.

Finally, the E component was divided from E1 to E6, with higher E numbers roughly correlating with the clinical predictability of the urethral tissue within and surrounding the urethral stricture during urethroplasty.

In validation testing using clinical vignettes along with retrograde urethrogram (RUG) images, the final kappa statistic for the overall "LSE" classification system was 0.79, indicating substantial agreement among reviewers, the researchers report in Urology.

When retrospectively applying the classification system to more than 2,000 urethral strictures in the TURNS database, S classification strongly predicted presumed stricture etiology and urethroplasty type.

"To classify is to begin to understand," Dr. Erickson said. "This is a first step towards a better understanding of how best to treat urethral stricture disease by location and etiology. Using the oncology model of classification, standardization of tissue histopathology will be the next phase in understanding this disease process."

He added that the LSE system needs to be validated clinically and that "we will need to develop an aid to help with easy classification (which is in the works)."

SOURCE: Urology, online June 21, 2020.