Oral melanoacanthoma: A rare case of diffuse oral pigmentation

Abstract

The clinical presentation of diffuse pigmentation can be alarming to the patient as well as the clinician. A histopathologic examination of a pigmented lesion is necessary in most of the cases in the oral cavity. Oral melanoacanthoma is a very rare diffuse pigmentation with no specific treatment required. It shows increased number of dendritic melanocytes in an acanthotic epithelium. We present a rare case of diffuse pigmentation in the oral cavity whose diagnosis was done on the basis of clinical presentation and histopathology. Also immunohistochemistry was done.

A rare case of oral melanoacanthoma

“…Peutz–Jeghers syndrome is an autosomal dominant disorder with variable inheritance, characterized by hamartomatous polyps in the gastrointestinal tract, mostly in the small intestine and pigmented mucocutaneous lesions. [5] In the present case, the patient had no previous or family history of any kinds of pigmented lesions or gastrointestinal polyposis.…”

“…[4] The diffuse oral pigmentation can also be seen in other conditions such as Peutz–Jeghers syndrome, Addison's disease and Laugier–Hunziker syndrome. [5]…”

“…Diffuse pigmentation of the oral mucosa and/or skin secondary to systemic drug administration is a well-recognized phenomenon. [5] The patient did not give any history of medications including oral contraceptive, steroids and antimalarial drugs.…”

“…Microscopically, numerous dendritic melanocytes are seen scattered throughout the epithelium. [25] Basal layer melanocytes may be increased in number, and spongiosis is a common finding. [4] The adjacent connective tissue stroma shows chronic inflammatory cell infiltrate.…”

“…It is a benign condition and no treatment is required once the diagnosis is confirmed. [25] Some cases regress spontaneously or following incomplete removal or elimination of local irritant. [1] In our case, the patient has been kept on regular follow-up for 6 months and the lesion remained unchanged during that time.…”