Let us learn about types of breast cancers, to spot, detect, treat, and prevent breast cancer.
Breast cancer develops in the cells of the breast. The type of cells that are affected determine the types of breast cancer. Carcinomas develop in the epithelial cells, but in breast cells carcinomas are specific – they are known as adenocarcinomas which develop either in the milk ducts or milk-producing glands.
Breast cancers are classified based on whether cancer has spread or not.
In situ breast cancer
- Ductal Carcinoma in situ (DCIS): Abnormal cells develop in the breast ducts and grow into cancer. Cancer develops in the milk ducts (tubes that carry milk) and has not spread into the rest of the breast tissue. It is also known as intraductal carcinoma. It is non-invasive or pre-invasive breast cancer.
Lobular carcinoma in situ (LCIS): Abnormal cells develop in the breast lobules and do not become cancerous and this condition rarely becomes invasive and cancerous. In women with this type of cancer, there is approximately 20 to 30% risk of LCIS becoming invasive over 15 to 20 years after initial diagnosis.
Invasive or Infiltrating Breast Cancer
This is any type of breast cancer that has invaded or spread into the surrounding breast tissues. Examples – invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC).
Up to 70 to 80% of breast cancers are IDC.
Invasive Ductal Carcinoma (IDC): It can spread to the lymph nodes and possibly to other areas of the body. It is common in older women and men also get this type of cancer.
- Tubular carcinoma of the breast (less aggressive as responding well to treatment)
- Medullary carcinoma of the breast (tumour appears like soft, fleshy mass – low grade and less aggressive in nature and easy to treat)
- Mucinous carcinoma of the breast – colloid carcinoma (abnormal cells of the tumour float in pools of mucin (a slimy and slippery component of mucus). Accounts for 2 to 3% of breast cancers. Less aggressive type as it responds well to treatment.
- Papillary carcinomas of the breast (rare 1 to 2%). Borders of cancerous cells have finger-like projections.
- Invasive cribriform carcinoma – cancer cells develop in the connective tissues and form nestlike formation between lobules and ducts (the growth appears like Swiss cheese). This is a rare type of cancer (5 to 6%) and appears low-grade.
Invasive Lobular Carcinoma (ILC) (Infiltrating Lobular carcinoma)
This is the second most common type of breast cancer. Abnormal cells develop in the breast lobules and become cancerous and spread to surrounding tissues. Around 10 t0 15% of breast cancers are of this type. Cancer cells can spread to lymph nodes and possibly to other areas of the body.
“Certain invasive breast cancers develop differently or have some special features, which may affect their treatment and prognosis. Though they are less common, they become aggressive, severe, and more serious than other types.”
For instance – Triple-negative breast cancer (accounts for up to 15%) and inflammatory breast cancer (accounts for up to 1 to 5%).
Inflammatory breast cancer (IBC)
In this type, abnormal breast cancer cells infiltrate the lymph vessels and skin of the breast. There is no distinct lump or tumour in this type. Therefore, during routine breast self-examination, a lump is not felt and detected within the breast. However, breast cancer cells block lymph vessels – and therefore, symptoms manifest.
Initially, a rash appears with persistent itching – and the inflamed or irritated breast area looks like an insect bite. The pores of breast skin dilate, the breast becomes red, swollen, and warm to touch. Breast skin looks like pitted orange peel; breast nipple flattened, invert or dimpling may occur.
Mastitis is a breast infection that carries similar symptoms, but if your gynaecologist says that it is breast infection (mastitis) and the symptoms persist even after antibiotics treatment, then you must consult a breast cancer specialist doctor as early as possible.
Other, less common types of breast cancer include:
Angiosarcoma: This type of cancer grows in the blood vessels and lymphatic vessels of the breast.
Phyllodes tumour: It is a very rare type of breast cancer that develops in the connective tissues of the breast. Mostly it is a benign type but can become cancerous.
Paget disease of the nipple: This type of breast cancer develops in the breast nipple. When it grows – the skin around the nipple and areola comes into its fold.