1807 Esophageal Melanocytosis: An Uncommon Finding

Abstract

INTRODUCTION: Esophageal melanocytosis is a benign, rare melanocytic proliferation in the basal layer of the squamous epithelium. The etiology of the melanocytosis is not clear; however, it has been suggested that aberrant migration during embryogenesis and chronic irritation such as GERD could lead to its occurrence. While largely asymptomatic, these proliferations raise concern for mucosal melanoma. CASE DESCRIPTION/METHODS: A 69-year-old Trinidadian female with past medical history of gastroesophageal reflux disease (GERD) presented with a two week history of dysphagia. Physical examination did not reveal any cutaneous or mucocutaneous lesions. Neurological exam also was normal. A computerized tomography (CT) scan showed circumferential wall thickening and moderate patulous proximal esophagus. A barium esophagram revealed severe esophageal dysmotility and GERD. Given dysphagia and CT findings, an esophagogastroduodenoscopy (EGD) was performed revealing hyperpigmented mucosa in the lower third of the esophagus (Figure 1A). Biopsies revealed melanin within the basal squamous epithelium with evenly spaced melanocytes and pigmented dendritic processes (Figure 1B). Immunohistochemistry for Melan-A and SOX10, a nuclear marker of melanocytes, highlighted these melanocytes without nesting or pagetoid scatter (Figure 1C). The patient was scheduled for a follow-up EGD for monitoring in 12 months. DISCUSSION: Endocscopically, anal and colonic lesions have been discovered along with esophageal lesions. Esophageal lesions largely present in the middle and lower third of the esophagus. Initial visualization of these lesions should be managed with a biopsy to determine if melanoma is present. Should esophagael melanocytosis be discovered on biopsy, repeat EGD with biopsy is recommended as early melanoma-in-situ may closely mimic esophageal melanocytosis.