Atypical vascular lesions

Benign vascular lesions occurring after radiotherapy. They may represent a precursor lesion to angiosarcoma.

Synonyms

Acquired lymphangiectasis, lymphangioma circumscriptum, benign lymphangiomatous papule.

Clinical features

The lesions present as small circumscribed papules, less than 5 mm in diameter, rarely up to 20 mm. They are often multiple. Most commonly they occur on the breast / chest wall after irradiation for breast carcinoma, less often after radiotherapy for other malignancies. To date, they have only occurred in women. The median age of occurrence is in the sixth decade, ten years earlier than for angiosarcoma and the latency after irradiation is only three years.

Histopathology

Atypical vascular lesions show similar appearances to hobnail haemangioma. The histological appearances overlap with those of post-radiation angiosarcoma. Like well-differentiated angiosarcoma, there are anastomosing vascular channels lined by endothelial cells which show nuclear hyperchromasia and hobnailing. Atypical vascular lesions do not extend into the subcutis.

Immunohistochemistry

	CD31	positive
	CD34	positive
	Factor VIIIRA	positive

Differential diagnosis

Atypical vascular lesion versus angiosarcoma

Prognosis

The behaviour is usually benign. Local recurrences may occur and patients may progress to develop angiosarcoma

References

1 Brenn T,Fletcher CD Postradiation vascular proliferations: an increasing problem. Histopathology 2006; 48:106-14

This page last revised 9.2.2006.