There are many varieties of breast cancer. Let’s understand the most common types first.
In Situ Cancers
Breast cancers are categorised as in situ if they have not spread beyond the duct or lobule where they formed. They are of two types:
A. Ductal carcinoma in situ (DCIS)
This cancer is formed in the pipes of the breasts. When ductal carcinoma is in stage 0 or the earliest stage, it is called DCIS. Since the cancerous cells are still in the milk ducts, the cancer is very much curable. However, not undergoing proper treatment on time, it can spread and become invasive.
B. Lobular carcinoma in situ (LCIS)
This cancer is formed in the lobules of the breasts. It isn’t precisely cancer but a marker that indicates that you are very likely to get cancer in the future. If you are diagnosed with it, you should regularly get breast exams & mammograms done to catch the disease in the beginning if it occurs.
Invasive Cancers
When breast cancer spreads beyond the boundaries of the breast, then it is called invasive cancer. It is further categorized into the following:
A. Invasive or infiltrating ductal carcinoma (IDC)
This cancer accounts for 4 to 5 cases of invasive cancers. It develops in the milk ducts and grows on to invade the fatty tissues of the breast.
B.Invasive lobular carcinoma (ILC)
Accounting for only 1 out of 10 cases, invasive breast cancer, this cancer forms in the lobules and later spreads to surrounding tissues as well as other body parts. Its subtypes include:
- Adenoid cystic (or adenoid cystic) carcinoma: These cancerous cells look like salivary glands and saliva.
- Low-grade adenosquamous carcinoma (a type of metaplastic carcinoma): A rare form of cancerous tumour which grows slowly and is often mistaken for other types of cancers.
- Medullary carcinoma: As the name suggests, they resemble the medulla of the brain and feel soft and squishy when touched.
- Mucinous carcinoma: These tumours are rare in nature and are found to be floating in a pool of mucin. Mucin is the substance which makes up most of the mucous.
- Papillary carcinoma: These cancerous cells have finger-like projections. They occur in women who are out of their menopause.
- Tubular carcinoma: These cancerous cells look like tubes and as their name says.
Now let’s look at the less common types of breast cancers.
Inflammatory Breast Cancer
This is rare types of cancer which occurs in the inflammatory cells found in the lymph vessels.
Paget’s Disease of the Nipple
This cancer occurs in the outer part of your breast. It affects the areola, i.e. the thin skin around your nipple.
Phyllodes Tumours of The Breast
Another rare type of cancer which grows in a leaf-like pattern. Although it proliferates, it rarely spreads beyond the breasts.
Metastatic Breast Cancer
This is a type of breast cancer which metastasises, i.e. spreads to different body organs like your brain, bones, lungs, etc. It is another name for the disease which is in its last stage, i.e. stage 4.
Triple-Negative Breast Cancer
It is another rare variety of cancer. It is only found in 10-20% of people who have breast cancer. It grows faster than any other types of breast cancers. It is also very difficult to cure because of its rapid growth and ineffectiveness of hormonal therapy against it.
It is recognised through three main characteristics:
- Lack of estrogen receptors: These receptors help the cell bind to estrogen hormone. Tumours with estrogen receptors can grow fast as estrogen stimulates their growth.
- Lack of progesterone receptors: These receptors help the cells to attach to the progesterone hormone.
- Lack of HER2 proteins: These cancerous cells do not have HER2 cells on their surface.
If a cancerous tumour shows all these characteristics, then it is called triple-negative breast cancer.
Male Breast Cancer
Breast cancer in men is sporadic. For every 70-100 cases of breast cancer in women, there is one case of breast cancer in men. However, if a disease occurs, it is as severe as it is for women. The signs and symptoms are also the same.