Question:

A 73-year old gentleman presented with a one-year history of persistent bruise-like lesions on the scalp. These had gradually increased in size. There had been no history of trauma and the lesions were asymptomatic.

Answer: C. Angiosarcoma

Angiosarcoma is a highly malignant neoplasm and is usually found in three settings.

It most commonly occurs in the elderly, presenting as a persistent bruise-like patch on the scalp or face. Men are more commonly affected. The diagnosis is often late and is frequently mistaken for cellulitis. With time, nodules, ulceration or plaques appear in the patches and growth is often rapid. Angiosarcoma may also rarely occur in cases of chronic lymphoedema, typically in women who have undergone mastectomy, axillary lymph node dissection and radiotherapy (Stewart-Treves syndrome). Angiosarcoma may also uncommonly occur after radiation usually after a lag period of ten years or more. The lower abdomen is a commonly affected site.

Diagnosis is by skin biopsy. Histologically, in the patch stage, there are vascular channels lined by large hyperchromatic endothelial cells infiltrating collagen bundles in the reticular dermis. Lymphocytic infiltrates can also be found. In the nodular or plaque stage, a more solid picture composed mainly of spindle cells is seen. Ulceration and necrosis may also be present. Histologically, angiosarcoma has to be distinguished from Kaposi's sarcoma.

Early diagnosis and wide excision are important for successful treatment. However, recurrence is common due to early extension into the subcutaneous tissue. Secondary spread is to the lungs, liver and lymph nodes. The prognosis is therefore poor. For large lesions, radiotherapy can be used.