There are several types of breast cancer, which are broken into two main categories: “invasive” (as mentioned above), and “noninvasive,” or in situ. While invasive cancer has spread from the breast ducts or glands to other parts of the breast, noninvasive cancer has not spread from the original tissue.
These two categories are used to describe the most common types of breast cancer, which include:
Ductal carcinoma in situ:
Ductal carcinoma in situ (DCIS) is a noninvasive condition. With DCIS, the cells that line the ducts in your breast change and look cancerous. However, DCIS cells haven’t invaded the surrounding breast tissue.
Lobular carcinoma in situ:
Lobular carcinoma in situ (LCIS) is cancer that grows in the milk-producing glands of your breast. Like DCIS, the cancer cells haven’t yet invaded the surrounding tissue.
Invasive ductal carcinoma:
Invasive ductal carcinoma (IDC) is the most common type of breast cancer. This type of breast cancer begins in your breast’s milk ducts and then invades nearby tissue in the breast. Once the breast cancer has spread to the tissue outside your milk ducts, it can begin to spread to other nearby organs and tissue.
Invasive lobular carcinoma:
Invasive lobular carcinoma (ILC) first develops in your breast’s lobules. If breast cancer is diagnosed as ILC, it has already spread to nearby tissue and organs.
Other, less common types of breast cancer include:
Paget disease of the nipple:
This type of breast cancer begins in the breasts’ ducts, but as it grows, it begins to affect the skin and areola of the nipple.
This very rare type of breast cancer grows in the connective tissue of the breast.
This is cancer that grows on the blood vessels or lymph vessels in the breast.
The type of cancer you have determines your treatment options, as well as your prognosis (likely long-term outcome). Learn more about types of breast cancer.
Inflammatory breast cancer
Inflammatory breast cancer (IBC) is a rare but aggressive type of breast cancer. IBC makes up only between 1 and 5 percent of all breast cancer cases.
With this condition, cells block the lymph nodes near the breasts, so the lymph vessels in the breast can’t properly drain. Instead of creating a tumor, IBC causes your breast to swell, look red, and feel very warm. A cancerous breast may appear pitted and thick, like an orange peel.
IBC can be very aggressive and progress quickly. For this reason, it’s important to call your doctor right away if you notice any symptoms. Find out more about IBC and the symptoms it can cause.
Triple-negative breast cancer
Triple-negative breast cancer is another rare disease type, affecting only about 10 to 20 percent of people with breast cancer. To be diagnosed as triple-negative breast cancer, a tumor must have all three of the following characteristics:
It lacks estrogen receptors. These receptors are cells that bind, or attach, to the hormone estrogen. If a tumor has estrogen receptors, it needs estrogen to grow.
It lacks progesterone receptors. These receptors are cells that bind to the hormone progesterone. If a tumor has progesterone receptors, it needs progesterone to grow.
It doesn’t have additional HER2 proteins on its surface. HER2 is a protein that fuels breast cancer growth.
If a tumor meets these three criteria, it’s labeled a triple-negative breast cancer. This type of breast cancer has a tendency to grow and spread more quickly than other types of breast cancer.
Triple-negative breast cancers are difficult to treat because traditional breast cancer treatments are not effective. Learn about treatments for triple-negative breast cancer, as well as survival rates.
Risk factors for breast cancer
There are several risk factors that increase your chances of getting breast cancer. However, having any of these doesn’t mean you will definitely develop the disease.
Some risk factors can’t be avoided, such as family history. Other risk factors, such as smoking, you can change.
Risk factors for breast cancer include:
- Age. Your risk for developing breast cancer increases as you age. Most invasive breast cancers are found in women over age 55.
- Drinking alcohol. Drinking excessive amounts of alcohol raises your risk.
- Having dense breast tissue. Dense breast tissue makes mammograms hard to read. It also increases your risk of breast cancer.
- Gender. Women are 100 times more likely to develop breast cancer than men.
- Genes. Women who have the BRCA1 and BRCA2 gene mutations are more likely to develop breast cancer than women who don’t. Other gene mutations may also affect your risk.
- Early menstruation. If you had your first period before age 12, you have an increased risk for breast cancer.
- Giving birth at an older age. Women who don’t have their first child until after age 35 have an increased risk of breast cancer.
- Hormone therapy. Women who took or are taking postmenopausal estrogen and progesterone medications to reduce their signs of menopause symptoms have a higher risk of breast cancer.
- Inherited risk. If a close female relative has had breast cancer, you have an increased risk for developing it. This includes your mother, grandmother, sister, or daughter. If you don’t have a family history of breast cancer, you can still develop breast cancer. In fact, the majority of women who develop it have no family history of the disease.
- Late menopause start. Women who do not start menopause until after age 55 are more likely to develop breast cancer.
- Never being pregnant. Women who never became pregnant or never carried a pregnancy to full-term are more likely to develop breast cancer.
- Previous breast cancer. If you have had breast cancer in one breast, you have an increased risk of developing breast cancer in your other breast or in a different area of the previously affected breast.