Skip to Navigation Skip to Search Skip to Content
Search All Centers

What Is Breast Cancer?

This overview gives you and your care partners medical information and personal insight that can help in this difficult time. Below you will find an introduction and breast cancer FAQ section to answer some of your most important questions; a video from a renowned oncologist, describing what she tells patients when they are first diagnosed; and written and video stories from two patients talking about their diagnosis and how they responded. We hope it proves useful as you navigate your illness.

Breast Cancer Symptoms and Causes

What is Usually the First Sign of Breast Cancer?

The earmark of breast cancer is a mass or lump that forms in the breast tissue, but there are other signs you can be aware of to stay ahead of a breast cancer diagnosis. These include:

  • Issues with the skin on your breast (excessive crusting or flaking, or redness and pitting, which the Mayo Clinic likens to the skin of an orange);
  • Unusual changes to the overall size of your breast;
  • Changes to your nipple, such as crusting of the skin around the areola or if you notice your areola has recently become inverted.

If you notice any unusual changes, talk to your doctor.

What are the Chances that a Breast Lump is Cancer?

If you find a breast lump, the first thing you should do is take a deep breath, because the chances are you have nothing to worry about. According to the Dana-Farber Cancer Institute, the vast majority of breast lumps are not cancerous. In fact, 80% of breast lumps are benign. However, it is important to have any new lumps checked out by a health professional.

What is the Difference Between a Benign Tumor and a Malignant Tumor in the Breast?

A tumor is a mass of cells that have overgrown, usually due to a malfunction in the DNA of the cells. A benign tumor usually pushes the normal tissue aside and doesn’t dissolve or invade healthy tissue. Malignant tumor cells have the ability to produce enzymes that invade healthy tissue in the area.

What is the Most Common Cause of Breast Cancer?

Breast cancer is caused when the genetic material in normal breast tissue cells (DNA) undergoes a change or mutation. When this results in mutated genes, which control how and when our cells divide and grow, cancer may occur.

Breast Cancer Risk Factors

What Makes You High Risk for Breast Cancer?

There are a number of factors to consider when determining whether or not you stand a high risk of developing breast cancer, including:

  • A family or personal history of breast cancer (meaning you’ve previously had the disease).
  • A personal history of other breast conditions and the presence of the BRCA1 and BRCA2 genes.
  • Increasing age (the disease is more common the older you get).
  • Exposure to radiation.
  • Having never been pregnant, or having been pregnant at a later age.
  • Health factors can contribute to the disease as well, women who are overweight or drink alcohol frequently are more susceptible.

How Can I Reduce My Risk of Developing Breast Cancer?

It can be difficult knowing certain factors are out of your control in terms of developing breast cancer, but there are still things you can do to reduce your risk of breast cancer:

  • Living a healthy lifestyle will better your odds for a cancer-free future. The Mayo Clinic cites research claiming both regular exercise and a healthy diet are important in prevention.
  • Additionally, it is recommended that women limit their use of hormone therapy after menopause. If hormone therapy is strongly recommended or preferred, taking lower doses can prove beneficial.
  • Becoming aware of your breasts with regular self-examination can also help you notice the early presence of any concerning lumps.
  • Lastly, make sure to talk to your doctor about screening. He or she will be able to tell you when to start getting regular exams or mammograms and can facilitate them.

Is Breast Cancer Hereditary?

The short answer is yes, breast cancer can be hereditary, but there’s more to it than that. Breast cancer arises from a number of different factors that are both acquired and hereditary.

According to the Mayo Clinic, between 5 and 10 percent of breast cancer cases are linked to inherited genes that have mutated. The best-known genes that contribute to the disease are breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2).

If you have any questions, talk to your doctor. They’re there to help.

Breast Cancer Diagnosis and Treatment

How is Breast Cancer Diagnosed?

There are several ways your doctor can test for breast cancer, but only one that will be able to tell you for certain. Here’s how the diagnostic process could look for you.

The most rudimentary test is a physical breast exam performed by you or your doctor. This will check for lumps, as well as any unusual activity in the lymph nodes of your armpit.

Other more sophisticated procedures include a mammogram (an x-ray of the breast), a breast ultrasound and a breast MRI. These can give medical professionals a better idea of what’s going on, but the only way to receive a sure diagnosis is by having a breast biopsy.

Likely, your doctor will start with one or more of the aforementioned procedures before moving on to a biopsy for confirmation. In a biopsy, a hollow needle will be used to withdraw a small amount of breast tissue that will then be examined under a microscope to determine an official diagnosis.

I’ve Been Diagnosed with Breast Cancer: Now What?

If you’ve recently been diagnosed with breast cancer, you may be feeling alone. Rest assured, however, that you are not.

For women, breast cancer is the second-most diagnosed form of the disease, behind only skin cancer. According to Susan G. Komen, one in eight women will be diagnosed with breast cancer in her lifetime. Although not as common, men can also develop breast cancer.

What are the Treatments for Breast Cancer?

It’s important to remember that breast cancer is a very treatable disease, and you have a vast array of medical help at your disposal.

Following a breast cancer diagnosis, you and your doctor will decide on a treatment plan based on a number of factors including grade, size, and how sensitive the cells are to hormones.

Make sure to talk with your doctor about all of your options, because at the end of the day, your course of treatment is your decision.

It can seem overwhelming, but there are many resources available to you. A few helpful steps you can take at this stage are to seek a second opinion from a breast cancer specialist and reach out to others who have faced breast cancer and made the same decision.

What Are the Differences Between Mastectomies and Lumpectomies?

The two most common surgical options for breast cancer treatment include a lumpectomy and a mastectomy.

Generally, a lumpectomy is paired with radiation therapy, and this combination is considered by experts to be as effective in terms of survival rates as a mastectomy. Radiation is sometimes combined with mastectomies; it is almost always combined with lumpectomies. Because of this, one reason to consider a mastectomy would be to avoid radiation treatment, for either personal or medical reasons, as it does carry its own list of side effects.

In addition, following a mastectomy, you will have lower chances of local cancer recurrence, although both procedures carry a very low chance of recurrence with early-stage breast cancer.

The mastectomy does come with its drawbacks as well. As it removes most or all of the breast tissue, many wish to pursue reconstructive surgery afterward. It is also a more involved surgical procedure than a lumpectomy, meaning it will require more recovery time to heal from.

Breast Cancer Side Effects

What are the Side Effects of Breast Cancer?

Your potential breast cancer side effects will depend largely on the treatment methods you and your doctor choose.

If you choose surgery — a lumpectomy, mastectomy, or removal of affected lymph nodes — the normal surgical risks, including bleeding and infection, can occur. If a mastectomy was your best treatment option, you may choose to look into options for breast reconstructive surgery as well.

The use of radiation may cause a rash resembling sunburn on your skin, while chemotherapy can cause nausea, fatigue, and hair loss. More serious damage to your kidney, liver, and heart can occur but is rare. Like in the case of a mastectomy, you have cosmetic options to counter hair loss and other side effects of radiation.

Lastly, hormone therapy can cause vaginal dryness, night sweats, and hot flashes, in addition to less common but more serious side effects such as blood clots and bone thinning.

If you’re opting for hormone therapy, hot flashes are a possible side effect, but there are a number of ways you can treat them.

According to the National Institutes of Health (NIH), dressing in layers and carrying a portable fan can provide you with some instant comfort. Breathing exercises can also be used to reduce stress and provide some relief. Several studies have shown positive outcomes for women who seek complementary therapies such as acupuncture in alleviating hot flashes.

There are also lifestyle-related measures you can take to ease the severity of your hot flashes. These include maintaining a healthy weight, as well as avoiding alcohol and tobacco.

Breast Cancer Stages and Survival

What are the Stages of Breast Cancer and What Do They Mean?

Breast cancer has a range of stages, between 0 and IV. Each breast cancer stage is calculated considering a combination of factors, abbreviated as T (the physical size of the tumor), N (whether or not the disease has reached the lymph nodes), and M (whether the cancer has spread outside the breast). Due to different combinations of these diagnostic categories, an A and B iteration exists for several stages.

What is Stage 0 Breast Cancer?

  • Stage 0 refers to cancer cells that are either considered non-invasive or fully contained within the cells of the milk duct.

What is Stage I Breast Cancer?

  • Stage IA: Cancer that has not spread to the lymph nodes with a tumor that measures up to 2 cm.
  • Stage IB: Cancer that may or may not be present in the breast (up to 2 cm) in addition to small groups of cancer cells in the nearby lymph nodes measuring between 0.2 mm and 2 mm.

What is Stage II Breast Cancer?

  • Stage IIA: No tumor found in the breast but cancer cells larger than 2 mm present in one to three nearby lymph nodes, or a tumor located in the breast between 2-5 cm with no cancer in nearby lymph nodes.
  • Stage IIB: The presence of a tumor in the breast between 2-5 cm; in addition to small groups of cancer cells between 0.2-2 mm in the lymph nodes.

What is Stage III Breast Cancer?

  • Stage IIIA: No tumor present in the breast but cancer found in four to nine nearby lymph nodes, or a tumor larger than 5 cm found in the breast with cancer cells between 0.2-2 mm in the lymph nodes.
  • Stage IIIB: The presence of any sized tumor that has spread to the tissue of the chest wall and/or the breast skin. Stage IIIB cancer may also have spread to nearby lymph nodes.

What is Stage IV Breast Cancer?

  • Stage IV: While Stage IV breast cancer doesn’t contain A and B subsets, it refers to cancer that has spread from the breast and auxiliary lymph nodes to other organs of the body, such as the lungs, brain, or bones.

What Stage is Breast Cancer in the Lymph Nodes?

Breast cancer of all stages can be found in the lymph nodes. The difference between how many nearby nodes are affected, and how large the cancer cells in the nodes are, helps denote the diagnosed stage of breast cancer.

However, it is generally recognized that stage III breast cancer (distant) impacts the lymph nodes significantly.

What is the Breast Cancer Survival Rate?

While it’s easy to get overwhelmed and afraid after learning about the disease, you can find some comfort in knowing that the survival rates for breast cancer are high. In fact, the American Cancer Society lists the five-year survival rate for localized breast cancer at 99%; and the survival rate for all stages at 90%. According to the Mayo Clinic, breast cancer survival rates have been steadily increasing, while negative outcomes are on the decline.

In stages I and II, breast cancer is still considered to be localized. If you’re diagnosed in these stages, you have a 99% chance of living at least another five years. It should also be noted that 62% percent of breast cancer diagnoses are given during these stages.

In stage III, the cancer is considered to be regional, and 85% of people live at least five more years.

Stage IV breast cancer is considered distant because at this point it has spread to other areas of the body. Individuals diagnosed with distant breast cancer see a 27% chance of living at least five more years, however only 6% of people are diagnosed in stage IV.

The prevalence of breast cancer has led to vast and effective options for both medical treatment and support. With new breast cancer therapies regularly becoming available — in addition to tried-and-true methods such as immunotherapy, hormone therapy, chemotherapy and targeted therapy — there is more than one way for you and your medical team to confront this disease.

If you have been diagnosed with breast cancer, are supporting someone you love through their breast cancer journey, are worried that you might have breast cancer, or are simply looking for more information about the disease, we are here for you. You do not have to face breast cancer alone.

Breast Cancer Definitions

What Are The Types of Breast Cancer?

Breast cancer is not one disease, it is better defined as a group of diseases. The types of breast cancer include:

  • Invasive Ductal Carcinoma vs Ductal Carcinoma in Situ
  • Lobular Carcinoma vs Lobular Carcinoma in Situ
  • Inflammatory Breast Cancer
  • HER2 Positive Breast Cancer
  • Triple-Negative Breast Cancer
  • Paget’s Disease of the Breast

Below are the definitions of the different types of breast cancer.

Invasive Ductal Carcinoma

In many cases, breast cancer starts within the milk-producing ducts and spreads outside of the ducts, where it’s referred to as Invasive Ductal Carcinoma (IDC).

Ductal Carcinoma in Situ (DCIS)

Ductal carcinoma in situ (DCIS) refers to the presence of cancerous cells contained within the milk duct of the breast. While it is considered a form of breast cancer, DCIS is also deemed non-invasive (meaning it has not yet spread outside of the milk ducts), and it is unlikely to become invasive.

While the Mayo Clinic defines DCIS as less serious than other aggressive types of breast cancer, it does still recommend treatment options, which can include surgery, radiation, or a combination of the two.

Lobular Carcinoma

Lobular carcinoma is a type of breast cancer that begins in the milk-producing glands (lobules) of the breast. If the cancer cells have escaped the lobules, it is considered invasive. Lobular carcinoma is the second common cellular subtype of breast cancer.

Lobular Carcinoma in Situ

Lobular carcinoma in Situ is when possible cancer cells in the lobules of the breast (milk-producing glands) are present but haven’t escaped the lobules. LCIS is not considered cancer but may increase your risk of invasive cancer in the future so it should be monitored.

Inflammatory Breast Cancer

When the cancer cells begin in the lymphatic vessels in the skin surrounding the breast, causing it to appear swollen, it is referred to as inflammatory breast cancer. Inflammatory breast cancer doesn’t appear as a lump but may have a sudden onset and can be easily mistaken as an infection.

HER2 Positive Breast Cancer

HER2 positive breast cancer is when the cancer cells test positive for a protein called human epidermal growth factor receptor 2 (HER2). When the HER2 protein is present, tumors generally develop faster. Any type of cancer testing positive for HER2 is considered more aggressive than other varieties. Luckily, it is only expressed in 15-25% of breast cancer diagnoses. There are many treatments for HER2 positive breast cancer that target the HER2 protein.

Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) differs from other types of breast cancer such as estrogen receptor (ER) progesterone receptor (ER) and human epidermal growth factor 2 (HER2) in the fact that it does not have any receptors or proteins on the cell that cause a reaction. Chemotherapy is often the course of treatment for triple-negative breast cancer.

Paget’s Disease of the Breast

Paget’s disease of the breast is a rare form of breast cancer that begins on the nipple and extends to the areola. It is more common in women over age 50 who have underlying ductal carcinoma.

Upcoming Events

See all events
Dec 15 2020
Episode 8 of 8 in Let's Talk Metastatic Breast Cancer

Let's Talk Metastatic Breast Cancer: What Does the Future Hold?

Tuesday, December 15, 2020
Time: 1:00 PM – 1:30 PM Pacific Time (US and Canada)

Metastatic breast cancer research is in an exciting phase with multiple treatments forthcoming. Yet the question remains: What does that mean for patients living with metastatic disease? 

Topic Area: Breast Cancer
Type: Online
Time: 1:00 PM – 1:30 PM Pacific Time (US and Canada)

Latest News