Other less common forms of breast cancer include:
• Inflammatory breast cancer (IBC) A rare type of invasive breast cancer, IBC accounts for about 1 to 2% of all breast cancers. It affects the lymphatic vessels in the skin of the breast, causing the breast to become red and inflamed.
• Mixed tumors: Mixed tumors contain a variety of cell types (e.g., IDC combined with ILC). Mixed tumors are treated as IDC.
• Medullary cancer: representing about 5% of breast cancer, the prognosis for medullary carcinoma is better than for other types of invasive breast cancer.
• Metaplastic tumors: A very rare variant of IDC, these tumors include cells that normally are not found in the breast. These tumors are treat similarly to IDC
• Mucinous carcinoma: Mucinous carcinoma is a rare type of invasive breast cancer characterised by mucos-producing cancer cells.
• Paget’s disease of the nipple: This is rare and accounts for 1% of cancers. Paget’s develops around the nipple. It causes redness and scaling of the nipple skin and can be mistaken for eczema. It is commonly associated with an invasive cancer elsewhere in the breast. ( Breast Care, June 2008, Trevor Smith)
• Phyllodes Tumor: Develops in the connective tissue of the breast. These tumours usually are benign but on rare occasions can be malignant.
• Tubular carcinoma: represents about 2% of all breast cancers. The majority of tubular cancers are hormone receptor positive, but HER-2 negative.
• Angiosarcoma: This cancer rarely occurs in the breast. When it does, angiosarcoma is usually a complication of breast radiation therapy and tends to develop about 5 to 7 years after radiation.
(Radiologic Technology January/Feburary 2008, Vol. 79/3)
• Triple Negative: Breast cancer cells that test negative for estrogen receptors (ER-), progesterone receptors (PR-) and HER2 (Her2-) is referred to as triple negative breast cancer. Therefore triple negative cancers do not respond to hormonal therapies. However other medications can be used to target Triple Negative.