A Solitary Lump on the Scalp

Abstract

A woman in her early 70s was referred to the dermatology department for evaluation of a solitary, asymptomatic lump on her scalp. She was born with the lesion but noticed some growth following a minor local trauma a couple of months prior to seeking medical evaluation. The patient denied local inflammation, purulent discharge, and systemic symptoms. Her medical history was unremarkable apart from an allegedly benign breast nodule resection in her teenage years. In addition, her father died of metastatic cutaneous melanoma at 83 years old.Clinically, there was an ill-defined, infiltrated plaque with a normochromic, exophytic nodule on her scalp vertex measuring 4.2 × 3.8 cm (Figure , A). It had a waxy surface with irregular transverse furrows and overlying alopecia. Dermoscopic evaluation findings revealed a homogeneous yellow hue with no visible vascular or pigmented structures and absence of follicular ostia. The lesion was firm and mildly tender to the touch and seemed adherent to the underlying bone. There were no palpable lymph nodes. A brain magnetic resonance imaging was performed for further elucidation (Figure, B), as well as a punch biopsy (Figure, C and D).Lesion on the scalp A T1-weighted brain MRI B Cellular infiltration C Monomorphic cells D 20 µm 100 µm Clinical Review & Education