angiolipoma

Angiolipoma is a benign soft tissue tumor composed of mature adipose tissue intermingled with proliferating small blood vessels. It is considered a variant of lipoma with a prominent vascular component. Clinically, angiolipomas present as small, tender, subcutaneous nodules, most often on the forearms of young adults, though they can occur in other sites.

Histologically, angiolipomas show lobulated adipose tissue with numerous capillaries and small, thick-walled veins, often containing fibrin thrombi within the capillary lumens. The lesion is typically well circumscribed, but a subset known as infiltrating angiolipoma grows into surrounding fascia or muscle and may be more difficult to excise.

Angiolipomas are most common in young adults, with a slight male predominance reported in some series. They can be solitary or multiple in a single individual.

Diagnosis is usually clinical, supported by imaging or histology. Ultrasound or MRI can identify a lesion with fat-containing signals and a vascular component; definitive diagnosis is by histopathology, usually after surgical excision or biopsy.

The standard treatment is complete surgical excision. The prognosis is excellent, as angiolipomas are benign with rare malignant potential. Recurrence is uncommon after complete removal, but infiltrating angiolipomas have a higher risk of recurrence and may require wider excision.