[Melanosis of the bladder: a very uncommon entity].

Melanosis of the bladder is a rare entity characterized by anomalous deposits of melanin-containing pigment on the vesical urothelium without melanocytic atypia or associated malignant melanoma. To our knowledge and following such strict criteria, there are only five cases previously reported. The biological potential of this entity is uncertain because of the rarity of their. We report one case of simple melanosis of the bladder confirmed by histological examination and inmunohistochemistry analysis. We believe that recognition of this entity is important.