As we continue to move forward in our understanding of anterior urethral stricture disease (aUSD), we must keep in mind that most aUSD looks like the retrograde urethrogram in the FIgure when they first present to a urologist. In the Trauma and Urologic Reconstruction Network of Surgeons (TURNS) prospective database, the short (L1/L2), proximal/mid-bulbar (S1a) urethral strictures of idiopathic origin (E2) make up over half of the nearly 3000 strictures in the cohort1. While this area is certainly vulnerable to straddle injury, the uniformity of the stricture appearance both on retrograde urethrogram and, shown in this manuscript, histopathology, should make us rethink how these strictures truly come to be.
Fortunately for our patients, urethroplasty techniques have made strictures in this area essentially curable, seemingly regardless of the type of repair that is performed – i.e. transection/non-transection, ventral/dorsal graft, excision/non-excision, all perform about the same when sound reconstructive techniques are applied. Unfortunately for clinicians and researchers, our successes surgically have prevented us from answering the most obvious question: why here and how? This study suggests that further work on our most common, and most surgically straight-forward, aUSD may be the key to unlocking improved non-surgical treatments and preventative strategies.
As suggested by the commentary above, the pathophysiologic mechanism of inflammation and fibrosis is common to many non-oncologic disease processes in urology, and a uniform approach to studying fibrosis in urologic organs is surely to benefit urologic disease processes beyond aUSD (e.g. erectile dysfunction, ureteral stricture, radiation cystitis/fibrosis). Notably, while we have historically considered fibrosis to be an irreversible process, advances in cardiac and pulmonary fibrosis suggest that the cells responsible for “protecting” the organ after injury are manipulatable and phenotypes can be reversed under the right conditions2,3. With continued discovery, we may soon be innovating our way out of the one of the most enjoyable, and successful, surgical procedures in all of urology.
Figure:
L1S1aE2 urethral stricture1
Funding
National Institutes of Health (NIH), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) 1R21DK115945-01
References
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