Abstract
Pigmented cellular nevus is possibly the most common skin lesion. However, cellular nevi of oral tissues are considered to be uncommon, only seven cases reported in Japan.
Theories about the origin of the nevus cell are controversial. Some investigators believe that nevus cells are derived from specialized cells in the epithelium and others suggest dermal nevus as the site of origin.
The purpose of this article is to add two new cases of pigmented nevi to the literature and to illustrate and discuss their clinicopathological features. The apparent rarity of the oral nevi may be due to a failure to report because in most patients the nevi are asymptomatic and the patients were not aware of their existence.
