Glomus tumor
Overview
Plain-Language Overview
Glomus tumor is a rare, benign growth that develops from the glomus body, a small structure involved in regulating blood flow and temperature in the skin. It most commonly occurs under the fingernails or toenails but can appear in other parts of the body. This tumor affects the circulatory system and causes intense, localized pain and sensitivity to cold. People with this condition often experience a small, tender lump that can cause sharp discomfort with even light touch or temperature changes. Although it is not cancerous, the tumor can significantly impact daily activities due to its painful nature. Diagnosis often involves identifying the characteristic symptoms and confirming with imaging or biopsy.
Clinical Definition
Glomus tumor is a benign neoplasm arising from the glomus body, a specialized arteriovenous shunt involved in thermoregulation. It is composed of modified smooth muscle cells called glomus cells and is typically found in the subungual region of digits. The tumor is characterized by a triad of paroxysmal pain, point tenderness, and cold sensitivity. Pathophysiologically, it results from proliferation of glomus cells leading to a vascular mass that compresses surrounding nerves. Although benign, it is clinically significant due to its severe pain and potential for misdiagnosis. Histologically, it shows nests of uniform glomus cells surrounding vascular channels. Surgical excision is the definitive treatment, confirming the diagnosis.