Beyond the Digits: A Rare Case of Extradigital Glomus Tumor of the Hand

Glomus tumors (GTs) are rare benign vascular neoplasms most commonly occurring in the subungual region of digits. Extradigital GTs are uncommon and often misdiagnosed due to the absence of the classical triad of localized pain, cold sensitivity, and tenderness. This report highlights the diagnostic challenges and emphasizes the need to consider extradigital GTs in extremity swellings. A 58-year-old male with diabetes, hypertension, and hypothyroidism presented with a gradually progressive swelling over the dorsum of the right hand for 5 months. . Examination revealed a 3 cm × 2 cm firm, mildly tender, and nonpulsatile swelling without restriction of hand movements. USG demonstrated a lobulated hyperechoic vascular lesion, while MRI showed a well-defined enhancing lesion suggestive of an arteriovenous malformation. Surgical excision was undertaken, and the specimen was subjected to histopathological and immunohistochemical analysis Histopathology revealed a highly cellular tumor with prominent vasculature and myxoid background, consistent with a GT of uncertain malignant potential (GT-UMP), as per the Folpe criteria. Immunohistochemistry (IHC) was diffusely positive for SMA and focally positive for CD34. Postoperative recovery was uneventful and the patient remained asymptomatic on follow-up. Extradigital GTs are rare and often overlooked due to atypical clinical features. Imaging may suggest a vascular lesion but is nonspecific; definitive diagnosis relies on histopathology and IHC. Complete surgical excision is curative in most cases. This case highlights the importance of considering GT-UMP in atypical extremity lesions mimicking vascular malformations.