Oncologists use pathological reports and imaging tests to understand which stage the cancer is at. The type of breast cancer depends on which part of the organ the cancer originated. This could be the milk ducts, the milk-producing lobules, the connective tissues etc.

Ductal carcinoma in-situ (DCIS)

This is a highly treatable form of pre-cancer (sometimes called ‘stage 0’ breast cancer). It starts in a milk duct and is the most common type of non-invasive breast cancer. In DCIS, the cells are abnormal but have not spread to the surrounding tissue areas. If left untreated over time, or if mistreated, DCIS may progress and evolve into an invasive form of breast cancer.

Invasive ductal carcinoma (IDC)

This is the most common type of breast cancer. It accounts for up to 80% of all cases of invasive breast cancer and is also known as ‘infiltrating ductal carcinoma’. Like DCIS, IDC also starts in a milk duct. It then breaks through the duct wall, and invades the surrounding breast tissue area. It has the potential to spread to other parts of the body as well.

Invasive lobular carcinoma (ILC)

This type of breast cancer begins in lobules, or the milk-producing glands present in breasts. It is also known as ‘infiltrating lobular carcinoma’. ILC has the potential to spread beyond the lobules, into the surrounding breast tissue and it can also metastasize to other parts of the body. It accounts for nearly 10% of all invasive forms of breast cancer.

Inflammatory breast cancer (IBC)

IBC is a rare and aggressive type of breast cancer. It causes redness and swelling in one or both breasts. The affected breast starts to feel warm, heavy, and tender. For IBC patients, the skin around the breast area becomes hard and ridged. It does not show up easily in a screening mammogram, and compared to other types of breast cancer, IBC tends to strike five years earlier.

Paget disease of the breast (or the nipple)

Paget disease is another rare type of cancer that affects the skin of the nipple and the areola (the darker circle of skin surrounding the nipples).

It should be differentiated from eczema of the nipple. For people affected with Paget disease, the nipple and areola often become scaly, red, or itchy. Patients may also experience yellow or bloody discharge from the nipples. Most people with Paget disease are likely to have underlying  invasive breast cancer or DCIS in the same breast.

Metaplastic breast cancer

Metaplastic breast cancer is also an extremely rare and invasive type of breast cancer. It begins in a milk duct, and proceeds to form very large tumours. It can contain a combination of cells that are different in appearance when compared to typical breast cancers, and it is generally harder to diagnose.

Angiosarcoma of the breast

Angiosarcoma is a rare soft tissue tumour of the breast. It occurs in a primary form without a known precursor, and a secondary form that has been associated with a history of breast tissue that has been previously exposed to radiation.

Understanding more about the type and  genetic makeup of your cancer helps your doctor to prescribe the right course of treatment from the available options