Types of Breast Cancer

Ductal Carcinoma in-situ: Generally divided into comedo (blackhead, the cut surface of the tumor demonstrates extrusion of dead and necrotic tumor cells similar to a blackhead) and non-comedo types. DCIS is early breast cancer confined to the inside of the ductal system. The distinction between comedo and non-comedo types is important as comedocarcinoma in-situ generally behaves more aggressively and may show areas of microinvasion (small areas of invasion through the ductal wall into surrounding tissue).

The surgical management is the same as for other types of breast cancer except axillary node sampling is not done, as only 1% of these lesions will have axillary metastasis. We recommend, however, that irradiation be given if treated with conservative breast surgery to reduce the recurrence rate from 21% without irradiation, to 5%-10% with irradiation. This is a controversial area of the treatment of breast cancer.

Infiltrating Ductal: The most common type of breast cancer representing 78% of all malignancies. These lesions can be stellate (star like in appearance on mammography) in appearance or well circumscribed (rounded). The stellate lesions generally have a poorer prognosis.

Medullary Carcinoma: Comprise 15% of breast cancers. These lesions are generally well circumscribed and may be difficult to distinguish from fibroadenoma by mammography or sonography. Medullary carcinoma is estrogen and progesterone receptor (prognostic indicator) negative 90% of the time. Medullary carcinoma usually has a better prognosis than ordinary breast cancer.

Infiltrating Lobular: Representing 15% of breast cancer these lesions generally present in the upper outer quadrant of the breast as a subtle thickening and are difficult to diagnose by mammography. Infiltrating lobular can be bilateral (involve both breasts). Microscopically, these tumors exhibit a linear array of cells (Indian filing) and grow around the ducts and lobules (targeting).

Tubular Carcinoma: Orderly or well differentiated carcinoma of the breast. These lesions make up about 2% of breast cancer. They have a favorable prognosis with nearly a 95% 10-year survival.

Mucinous Carcinoma: Represents 1%-2% of carcinoma of the breast and has a favorable prognosis. These lesions are usually well circumscribed (rounded).

Inflammatory Breast Cancer: A particularly aggressive type of breast cancer the presentation is usually noted in changes in the skin of the breast including redness (erythema), thickening of the skin and prominence of the hair follicles resembling an orange peel (peau d' orange). The diagnosis is made by a skin biopsy, which reveals tumor in the lymphatic and vascular channels 50% of the time.

Source: nationalbreastcancer.org