Supporting the role of penile trauma and micro-trauma in the etiology of Peyronie’s disease. Prospective observational study using the electronic microscope to examine two types of plaques

Objectives: The etiopathogenesis of Peyronie’s disease (PD) remains not clearly understood. The most accepted theory attributes the histological lesions of PD to the effects of trauma to the corpora cavernosum of the penis. The aim of our study is to verify whether similar histological features exist between these two tissues, providing new evidence in favor of the traumatic theory in the etiopathogenesis of Peyronie’s disease. Materials and methods: A prospective observational study was carried out at our institution from January 2013 to June 2018, involving patients having undergone surgery for PD and those with delayed surgery for penile trauma. Both excised PD and post-traumatic plaques were analyzed by blind pathologists with an 80kV potential acceleration electron microscope. Results: Five patients were identified with a post-traumatic plaque (Group 1) and therefore an equal number of PD patients were enrolled for Group 2. The ultrastructural characteristics of the two types of preparations were very similar. In all the samples we showed an inflammatory reaction of the structure of the tunica albuginea, a production of the disorganized extracellular matrix, a proliferation of inflammatory cells and fibroblasts. Furthermore, we have found an increase in the density and collagen deposits grouped in the extracellular space and within the fibroblasts. Conclusions: These findings support the theory that attributes lesions and symptoms typical of PD to the effects of cavernous body trauma.