Melanoacanthomatous hyperplasia of the oral cavity: histological and histochemical study

ABSTRACT

Melanoacanthomatous hyperplasia of the oral cavity is a rare reactive phenomenon analogous histologically to the skin melanoacanthoma. A few cases were previously reported in the literature under the name "oral melanoacanthoma". This study comprised the largest series and the first to be found in Asians. Fourteen cases were detected among 27 unclassified melanotic lesions, in which a definite history of trauma was documented in five cases. Histologically, bicellular proliferative reaction of dendritic melanocytes and squamous cell proliferation, which along with evidence of inflammation in the underlying lamina propria may characterize the lesion as a part of a spectrum of reactive process rather than neoplasia