Angiosarcoma of breast

Breast angiosarcomas are a rare vascular breast malignancy.

Epidemiology

As primary tumors of the breast, they account for ~0.04% ² of all breast cancers and tend to occur in younger women, in their 3^rd to 4^th decades.

Secondary angiosarcoma, related to prior therapy of breast cancer, has an estimated incidence of ~0.09-0.16% and occurs in older women (peak age 6^th decade ²).

Clinical presentation

The classic presentation is a painless localized blue or purple color change of the breast skin, with singular or multifocal lesions which may resemble other benign vascular lesions such as angioma or telangiectasis ^9,10.

Patients may also present with swelling, a sensation of fullness, or rapid breast growth ¹⁰.

Pathology

The tumors are of endovascular origin. There are two main types:

• primary angiosarcoma of the breast
• secondary angiosarcoma of the breast
  • radiation-induced angiosarcoma: can occur following breast irradiation
  • lymphoedema-associated cutaneous angiosarcoma

Location

Specific location of the tumor varies according to whether it is a primary or secondary lesion:

• primary breast angiosarcoma are thought to arise within the breast parenchyma, with secondary involvement of the skin ¹¹
• secondary breast angiosarcoma mainly involve the skin, with or without involvement of underlying breast parenchyma ¹¹

Associations

• prior breast irradiation: radiation-induced breast angiosarcomas tend to occur after a significant latent period post-radiation (~5 years)
• Stewart-Treves syndrome

Radiographic features

Mammography

Lesions can sometimes be occult on mammography ⁷.

Breast MRI

A heterogeneous mass is usually seen on MRI. Reported signal characteristics include ⁷:

• T1: usually low signal intensity
• T2: usually high signal intensity
• C+ (Gd): low-grade lesions show progressive enhancement whereas high-grade lesions show rapid enhancement and washout

Treatment and prognosis

Angiosarcoma of the breast is an extremely aggressive tumor and is associated with a poor prognosis.

The tumor may be mis-diagnosed on the basis of fine-needle biopsy; thus, core biopsy is mandatory for diagnosis ¹².

Surgical excision with wide margin is the standard of care, typically a mastectomy.  Axillary nodal dissection is usually not performed, as the malignancy features haematogenous spread.

Despite aggressive surgery, there is a high local and distant recurrence rate.