9 Types of Breast Cancer Everyone Should Know About
Knowing the difference between the various types of breast cancer could save your life.
Chances are you know someone with breast cancer: Roughly 1 in 8 American women will develop breast cancer in her lifetime. Even still, there's a good chance you don't know much about all the different types of breast cancer someone can have. Yep, there are a lot of variations of this disease and knowing them just might save your (or someone else's) life.
What is breast cancer?
"Breast cancer is a large bucket term that encompasses all cancers that are in the breast, but there are multiple types of breast cancer and multiple ways to categorize them," says Janie Grumley, M.D., a breast surgical oncologist and director of the Margie Petersen Breast Center at Providence Saint John's Center Santa Monica, CA.
How do you determine what type of breast cancer someone has?
The important definers are whether breast cancer is invasive or not (in-situ means the cancer is contained within the breast ducts and unable to spread; invasive has the potential to travel outside the breast; or metastatic, meaning the cancer cells have traveled to other sites in the body); the origin of the cancer as well as the type of cells it's affecting (ductal, lobular, carcinoma, or metaplastic); and what kind of hormonal receptors are present (estrogen; progesterone; human epidermal growth factor receptor 2 or HER-2; or triple-negative, which has none of the aforementioned receptors). Receptors are what signal the breast's cells (cancerous and otherwise healthy) to grow. All of these factors influence the type of treatment that will be most effective. Typically, the type of breast cancer will include all this information in the name. (Related: Must-Know Facts About Breast Cancer)
We know—that's a lot to remember. And because there are so many variables, there are a lot of different types of breast cancer—once you start getting into the subtypes, the list grows to more than a dozen. Some types of breast cancer, though, are more common than others, or are super important for determining your overall cancer risk; here's a rundown of nine you should definitely know about.
Different Types of Breast Cancer
1. Invasive Ductal Carcinoma
When most people think of breast cancer, it's likely a case of invasive ductal carcinoma. This is the most common type of breast cancer, comprising nearly 70 to 80 percent of all diagnoses, and is usually detected via mammogram screenings. This type of breast cancer is defined by abnormal cancer cells that start in the milk ducts but spread to other parts of the breast tissue, sometimes other parts of the body. "Like most breast cancers, there are usually no signs until later stages," says Sharon Lum, M.D., director of the Loma Linda University Breast Health Center in California. "However, someone with this type of breast cancer can experience thickening of the breast, skin dimpling, swelling in the breast, rash or redness, or nipple discharge."
2. Metastatic Breast Cancer
Also often just called 'stage 4 breast cancer', this type of breast cancer is when the cancer cells have metastasized (i.e spread) to other parts of the body—usually the liver, brain, bones, or lungs. They break away from the original tumor and travel through the bloodstream or the lymphatic system. In the early stages of the disease, there are no obvious signs of breast cancer, but at later stages, you may see dimpling of the breast (like the skin of an orange), changes in the nipples, or experience pain anywhere in the body, says Dr. Lum. Stage 4 cancer obviously sounds terrifying, but there are many promising new targeted therapies giving women with metastatic breast cancer a chance for much longer survival, she adds.
3. Ductal Carcinoma In Situ
Ductal carcinoma in situ (DCIS) is a form of non-invasive breast cancer where abnormal cells have been found in the lining of the breast milk duct. It's not often marked by symptoms, but sometimes people may feel a lump or have bloody nipple discharge. This form of cancer is a very early stage cancer and highly treatable, which is great—but that also ups your risk for overtreatment (read: potentially unnecessary radiotherapy, hormonal therapy, or surgery for cells that may not spread or be cause for further concern). Though, Dr. Lum says that new studies have been looking at active surveillance for DCIS (or observation only) to avoid this.
4. Invasive Lobular Carcinoma
The second most common type of breast cancer is invasive lobular carcinoma (ICL), and it accounts for about 10 percent of all invasive breast cancer diagnoses, according to the American Cancer Society. The term carcinoma means that a cancer begins in a specific tissue and then eventually covers an internal organ—in this case the breast tissue. ICL specifically refers to cancer that has spread through the milk-producing lobules in the breast and has since begun to invade the tissue. Over time, ICL can spread to the lymph nodes and potentially other parts of the body. "This type of breast cancer can be difficult to detect," says Dr. Lum. "Even if your imaging is normal, if you have a lump in your breast, get it checked out." (Related: This 24-Year-Old Found a Breast Cancer Lump While Getting Ready for a Night Out)
5. Inflammatory Breast Cancer
Aggressive and fast-growing, this type of breast cancer is considered stage 3 and involves cells that infiltrate the skin and lymph vessels of the breast. Often there's no tumor or lump, but once the lymph vessels become blocked, symptoms like itching, rashes, insect bite-like bumps, and red, swollen breasts may appear. Because it mimics a skin condition, this type of breast cancer can easily be mistaken for an infection, says Dr. Lum, so make sure you get any abnormal skin conditions checked by your derm and then your doc if it doesn't improve with any derm-suggested methods. (Related: The Link Between Sleep and Breast Cancer)
6. Triple-Negative Breast Cancer
This is a serious, aggressive, and difficult-to-treat type of breast cancer. As the name might suggest, the cancer cells of someone with triple-negative breast cancer test negative for all three receptors, which means common treatments like hormone therapy and prescription medication that target the estrogen, progesterone, and HER-2 aren't effective. Triple-negative breast cancer is typically treated instead with a combination of surgery, radiation therapy, and chemotherapy (which is not always effective and comes with many side effects), says the American Cancer Society. This form of cancer is more likely to affect younger people, African-Americans, Hispanics, and those with the BRCA1 mutation, according to generic research.
7. Lobular Carcinoma In Situ (LCIS)
Not to confuse you, but LCIS is actually not considered a type of breast cancer, says Dr. Lum. Instead, this is an area of abnormal cell growth inside the lobules (the milk-producing glands in the breast ducts). This condition doesn't cause symptoms and usually doesn't show up on a mammogram, but is most often diagnosed in women between 40 and 50 years old as a result of a biopsy performed on the breast for some other reason. Even though it isn't cancer, per se, LCIS increases your risk of developing invasive breast cancer later in life, so it's super important to be aware of when thinking proactively about your overall cancer risk. (Related: The Latest Science On Your Breast Cancer Risk, Explained By Doctors)
8. Male Breast Cancer
Yes, men can get breast cancer. Beyoncé's dad actually just revealed he is dealing with the disease and wants to raise more awareness for men and women to be in-the-know. While only 1 percent of all breast cancer occurs in men and they do have significantly less volume of breast tissue, high estrogen levels (either naturally-occurring or from hormonal medications/drugs), a genetic mutation, or certain conditions like Klinefelter syndrome (a genetic condition where a male is born with an extra X chromosome) all increase a man's risk of developing cancer in his breast tissue. Plus, they can develop the same types of breast cancer as women (i.e., the others on this list). However, for men, cancer in this tissue is often a sign that they have a genetic mutation that makes them more susceptible to developing all kinds of cancer, says Dr. Grumley. That's why it's super important any man who has been diagnosed with breast cancer get genetic testing to understand their overall cancer risk, she adds.
9. Paget's Disease of the Nipple
Paget's Disease is quite rare and is when cancer cells collect in or around the nipple. They usually affect the ducts of the nipple first, then spread to the surface and the areola. That's why this type of breast cancer is often marked by scaly, red, itchy, and irritated nipples and is often mistaken for a rash, says Dr. Lum. Even though Paget's Disease of the nipple accounts for less than 5 percent of all breast cancer cases in the US, more than 97 percent of people with this condition also have another type of breast cancer (either DCIS or invasive), so it's good to be aware of the condition's symptoms, reports the American Cancer Society.