Immunohistochemical clues to the diagnosis of Mondor's disease of the penis.

Mondor's disease of the penis is usually a benign, self-limiting process of acute onset. To date, there have been few studies about its diagnosis and treatment. It is difficult to differentiate MD of the penis from sclerosing lymphangitis of the penis, because the symptoms, epidemiology and aetiology are similar, and because veins are histologically very similar to lymphatics. We report a case of MD in which immunochemical markers such as CD31 and D240 allowed us to specifically discriminate between the small vein and lymphatic vessels. This is important not only for the recognition of MD at any site, but for many other diseases in which veins or lymphatic vessels are affected.