Breast Cancer: Types & Risk Factors
Did you know?
Breast cancer is the most common cancer among women all over the world, with an estimated 1.67 million new cancer cases diagnosed in 2012 (25% of all cancers). In India, more than 1 lakh women are diagnosed with Breast Cancer every year & out of every 2 diagnosed cases of Breast Cancer, one is dying. Though breast cancer is more common in females, but males are also at risk of developing breast cancer.
Awareness of early signs of breast cancer and action for timely diagnosis and treatment of Breast cancer is the key to survival.
What is Breast Cancer?
Breast cancer is a disease in which cancer cells form in the breast tissue. The early signs of breast cancer are –
- A lump or a thickening in or near the breast – In most cases the lump is not painful
- A lump or thickening in underarm area
- A change in size or shape of breast
- A dimple or puckering in skin of the breast
- Inward pulling of nipple
- Fluid, other than breast milk, especially if it is bloody
- Altered skin colour or texture of breast, nipple, areola
- Dimpling of skin of breast – like a skin of Orange
Why do I need to know about Breast Cancer?
There are several factors which may put someone to more risk than others for developing the disease. Having a risk factor does not mean that one will get cancer. Also if there is no risk factor, it does not mean that one will not suffer from cancer.
Risk Factors for Breast cancer
- Early menarche & late menopause
- Older age at first birth or never having given birth
- No breast feeding
- Family History of Breast cancer
- Genetic factors
- Dense breast tissue
- Oral Contraceptive pills
- Not getting enough exercise
Classification of Breast Cancer
Two of the main parameters used for classification of the breast cancer are based on the histological types and receptor status. These two parameters give a specific understanding of the causes, the extent of the disease and the treatment procedure to be followed.
The primary classification of breast cancer is carried out on the basis of the histological appearance. A majority of breast cancers are derived from the epithelium lining of lobules or ducts. These cancers are classified as ductal or lobular carcinoma.
The two subtypes of this classification are:-
Carcinoma in Situ- This subtype includes cancerous or precancerous cells’ growth inside a specific tissue compartment such as the mammary duct. The growth does not invade the surrounding cells.
Invasive Carcinoma- This subtype is far more dangerous, with the cancerous growth not limiting itself to the site of origin. The cancerous cells invade the tissues surrounding the tissue compartment where the growth first started.
Receptors are present on the surface, cytoplasm and nucleus of breast cancer cells. The receptor status of these cells is determined by immunohistochemistry. The three main receptors present in the breast cancer cells include
- Estrogen Receptors (ER)
- Progesterone Receptors (PR)
ER and PR depend on estrogen and progesterone respectively for their growths while the HER2/neu grows with an amplification of the ERBB2 gene. The assessment of receptor status proves helpful in terms of establishing the suitability of different targeted treatments like Trastuzumab and oral hormonal therapy.
TNBC – Triple-negative breast cancer
TNBC refers to any breast cancer that does not express the genes for estrogen receptor (ER), progesterone receptor (PR) and Her2/neu. TNBC may be more aggressive form of tumor & may be difficult to treat.