Inflammatory Breast Cancer

Inflammatory breast cancer is a rare and aggressive form of breast cancer that causes the breast to look red, swollen, and inflamed, often without a lump that can be felt.

Table of contents

• What Is Inflammatory Breast Cancer?
• Signs and Symptoms
• Who Is More Likely to Develop This Cancer?
• How Is It Diagnosed?
• Treatment Approaches
• Outlook and Survival

What Is Inflammatory Breast Cancer?

Inflammatory breast cancer is a rare but very aggressive type of breast cancer. It accounts for about 1 to 5 percent of all breast cancers diagnosed in the United States^[1][2]. Despite being uncommon, this cancer contributes to about 7 percent of deaths caused by breast cancer^[3].

The disease is called “inflammatory” because the breast often looks swollen and red, or inflamed. This happens when cancer cells block small tubes called lymphatic vessels in the skin of the breast. These vessels normally carry fluid away from tissues, but when they become blocked, fluid builds up and causes the breast to swell and change appearance^[4][5].

Most inflammatory breast cancers are invasive ductal carcinomas, which means they started in the cells lining the milk ducts of the breast and then spread beyond the ducts^[6].

This cancer progresses very quickly, often developing over just a few weeks or months^[7]. By the time it is diagnosed, inflammatory breast cancer is usually at an advanced stage. It is classified as either stage III or stage IV, depending on whether the cancer has spread only to nearby lymph nodes or to other parts of the body^[8].

Signs and Symptoms

Unlike most other types of breast cancer, inflammatory breast cancer does not usually cause a lump that you can feel^[9]. Instead, the signs and symptoms develop rapidly and affect the appearance and feel of the breast. These changes often appear within weeks or months^[10].

Common symptoms include:

• Swelling or enlargement of one breast, making it larger than the other
• Redness of the breast skin, which may also appear pink, purple, or bruised, depending on your skin tone^[11]
• Thickened or dimpled skin that may look like the peel of an orange (called peau d’orange)^[12]
• A breast that feels warm, heavy, firm, or tender
• A nipple that points inward (inverted nipple) or has flattened^[13]
• Pain, itchiness, or a burning sensation in the breast
• Swollen lymph nodes under the arm or near the collarbone^[14]

It is important to know that these symptoms can also be caused by a breast infection called mastitis, which is much more common, especially in women who are pregnant or breastfeeding^[15]. Because of this, doctors may first prescribe antibiotics to see if the symptoms go away. However, if symptoms do not improve after taking antibiotics, further testing for inflammatory breast cancer is necessary^[16].

If you notice any of these changes in your breast that last longer than a week, you should see your doctor right away^[17].

Who Is More Likely to Develop This Cancer?

Inflammatory breast cancer tends to be diagnosed at younger ages compared to other types of breast cancer^[18]. It develops more often in younger women and women of African ancestry^[19].

Having a high body mass index (a measure of body weight compared to height) is an independent risk factor for inflammatory breast cancer. Women who have obesity are more likely to develop this type of cancer than women of normal weight^[20][21].

Unlike some other breast cancers, inflammatory breast cancer does not appear to be strongly linked to inherited genetic mutations or family history^[22].

How Is It Diagnosed?

Diagnosing inflammatory breast cancer can be challenging. The disease often does not create a lump that can be felt during a physical exam or seen on a routine mammogram (a breast X-ray)^[23]. Additionally, many women with this cancer have dense breast tissue, which makes it even harder to detect cancer on a mammogram^[24].

Because inflammatory breast cancer grows so quickly, it can develop between scheduled mammogram screenings. The symptoms may be mistaken for a breast infection, which can lead to delays in diagnosis^[25].

To diagnose inflammatory breast cancer, doctors use several tests and procedures:

Physical examination: Your doctor will examine your breast to look for changes in skin color, swelling, warmth, and other signs of inflammatory breast cancer. They will also ask about your symptoms and when you first noticed changes^[26].

Imaging tests: These tests create pictures of the inside of your breast. You may have a mammogram, a breast ultrasound (which uses sound waves to create images), or an MRI scan (which uses magnets and radio waves to create detailed images)^[27].

Biopsy: A biopsy involves removing a small sample of tissue from your breast to be tested in a laboratory. The tissue may be removed using a needle that is inserted through the skin. A skin biopsy may also be done to remove a sample of skin cells. The samples are tested to see if cancer is present^[28].

If cancer is found, the laboratory will also check for special proteins called receptors on the cancer cells. These receptors help the cancer grow and can affect which treatments will work best^[29].

Many inflammatory breast cancers do not have hormone receptors, which means they cannot be treated with hormone therapy drugs^[30].

You may also have additional tests to see if the cancer has spread to other parts of your body. These tests may include a CT scan (computed tomography scan), PET scan (positron emission tomography scan), or a bone scan^[31].

Treatment Approaches

Because inflammatory breast cancer is aggressive and often diagnosed at an advanced stage, treatment usually involves a combination of therapies used in a specific order^[32].

The typical treatment approach includes:

Chemotherapy first: Treatment usually begins with chemotherapy, which uses drugs to kill cancer cells. This is called neoadjuvant therapy. The goal is to shrink the cancer before surgery^[33]. If the cancer cells have certain receptors, you may also receive targeted therapy drugs along with chemotherapy. For example, if your cancer has HER2 receptors, you might receive a drug called trastuzumab (Herceptin)^[34].

Surgery: After chemotherapy, you will usually have surgery to remove the breast. This operation is called a mastectomy. The surgeon will remove the entire breast and may also remove lymph nodes under your arm^[35]. After a mastectomy, you may be able to have breast reconstruction surgery to rebuild the shape of your breast.

Radiation therapy: After surgery, you will have radiation therapy, which uses high-energy X-rays to kill any remaining cancer cells. This helps prevent the cancer from coming back^[36].

Additional therapy: If your cancer has hormone receptors, you will take hormone therapy pills for several years after completing other treatments. The goal is to lower the risk of the cancer returning^[37].

Outlook and Survival

Inflammatory breast cancer tends to have a lower survival rate than other types of breast cancer. This is because it grows and spreads very quickly, has a high risk of coming back after treatment, and is often not found until it has reached an advanced stage^[38].

According to statistics from the United States, the 5-year relative survival for inflammatory breast cancer is 41 percent. This means that, on average, people diagnosed with inflammatory breast cancer are 41 percent as likely to live for at least 5 years after diagnosis as people who do not have this cancer^[39].

However, it is important to remember that survival depends on many individual factors, including the stage of the cancer, how it responds to treatment, and your overall health. Doctors believe that the outlook for inflammatory breast cancer is improving as treatment approaches continue to advance^[40].

• Breast tissue
• Lymphatic vessels
• Milk ducts
• Lymph nodes
• Breast skin