The man behind the eponym: C. L. Pierre Masson.

This report traces the life of Pierre Masson and mentions some of his investigations. It summarizes Masson's seminal descriptions of glomus tumor and hémangioendothéliome végétant intra-vasculaire (intravascular papillary endothelial hyperplasia), also known as Masson's pseudoangiosarcoma and the Masson lesion. Finally, we reprise Masson's view of the origins of melanocytic nevi and mention Masson's neuronevus. The literature on these subsequent to Masson's articles is not discussed.