Diagnosis and Excision of Glomangioma of the Lower Extremity.

Glomangiomas are rare, benign vascular tumors originating from the specialized arteriovenous structure known as the glomus body. These tumors typically occur in subungual or digital locations, such as the fingers and toes. However, extradigital glomangiomas, which develop in other areas of the body, are much less common. When present in atypical sites, these lesions often mimic more prevalent subcutaneous abnormalities, such as sebaceous cysts, lipomas, or dermatofibromas, posing significant diagnostic challenges for clinicians. The nonspecific clinical features of extradigital glomangiomas, particularly the absence of hallmark symptoms like severe localized pain or hypersensitivity, can further complicate the diagnostic process. This case report describes a 67-year-old male who presented with a 1-cm soft, mobile, and asymptomatic lesion near the right knee, initially presumed to be a sebaceous cyst. Following unsuccessful drainage attempts, the lesion was surgically excised. Histopathological examination confirmed the diagnosis of a glomangioma, with glomus cells arranged around branching vascular channels and positive staining for smooth muscle actin and vimentin. Glomangiomas should be considered in the differential diagnosis of persistent subcutaneous masses in unusual locations. Greater recognition of these rare lesions can facilitate timely and appropriate management.