# Diagnosis and Excision of Glomangioma of the Lower Extremity

## TL;DR

This paper presents a case of a rare glomangioma tumor in an unusual location on the knee, highlighting diagnostic challenges and confirming the diagnosis through surgery and histopathology.

## Contribution

The paper adds a rare clinical case of extradigital glomangioma and emphasizes its importance in differential diagnosis for subcutaneous masses.

## Key findings

- A 67-year-old male had a subcutaneous lesion near the knee diagnosed as glomangioma after surgical excision.
- Histopathology showed glomus cells around vascular channels with positive staining for smooth muscle actin and vimentin.
- Extradigital glomangiomas should be considered in the differential diagnosis of persistent subcutaneous masses in atypical locations.

## Abstract

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.