Abstract

Desmoplastic melanoma (DM) is a rare malignant melanoma variant. Although DM mainly affects the skin chronically exposed to the sun, a small number of mucosal DM have been reported. Primary mucosal DM is difficult to diagnose because of its rarity and atypical histopathologic features. Here, we report a case of DM in a 52 year-old female who presented with a right cervical mass and upper gingival pigmentation. A CT scan revealed an ill-defined infiltrative mass 2 cm in size under the pigmented mucosa. She subsequently underwent a partial maxillectomy with neck dissection. Gross examination revealed that the mass exhibited a grayish white fibrotic cut surface and that the maxillary bone had been destroyed. Microscopically, the main mass was composed of cigar-shaped or wavy spindle cells with desmoplastic stroma under the melanoma in situ. The diagnosis of DM was confirmed immunohistochemically with S100 protein positivity and HMB45 negativity. The patient has survived for 29 months after the operation with a presumed metastatic focus.

• Keywords: Desmoplastic;Melanoma;Mouth mucosa