Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is a rare and aggressive type of invasive breast cancer in which cancer cells block lymph vessels in the skin. This causes the breast to look “inflamed.”

What is inflammatory breast cancer?

Inflammatory breast cancer (IBC) is rare. It accounts for only 1% to 5% of all breast cancers. Although it is a type of invasive ductal carcinoma, its symptoms, outlook, and treatment are different. IBC causes symptoms of breast inflammation like swelling and redness, which is caused by cancer cells blocking lymph vessels in the skin causing the breast to look "inflamed."

Inflammatory breast cancer (IBC) differs from other types of breast cancer in many ways:

• IBC doesn't look like a typical breast cancer. It often does not cause a breast lump, and it might not show up on a mammogram. This makes it harder to diagnose.
• IBC tends to occur in younger women (younger than 40 years of age).
• Black women appear to develop IBC more often than White women.
• IBC is more common among women who are overweight or obese.
• IBC tends to be more aggressive—it grows and spreads much more quickly—than more common types of breast cancer.
• IBC is always at least at a locally advanced stage when it’s first diagnosed because the breast cancer cells have grown into the skin. (This means it is at least stage III.)
• In about 1 of 3 cases, IBC has already spread (metastasized) to distant parts of the body when it is diagnosed. This makes it harder to treat successfully.
• Women with IBC tend to have a worse prognosis (outcome) than women with other common types of breast cancer.

Signs and symptoms of inflammatory breast cancer

Inflammatory breast cancer (IBC) can cause a number of signs and symptoms, most of which develop quickly (within 3 to 6 months), including:

• Swelling (edema) of the skin of the breast
• Redness involving more than one-third of the breast
• Pitting or thickening of the skin of the breast so that it may look and feel like an orange peel
• A retracted or inverted nipple
• One breast looking larger than the other because of swelling
• One breast feeling warmer and heavier than the other
• A breast that may be tender, painful, or itchy
• Swelling of the lymph nodes under the arms or near the collarbone

If you have any of these symptoms, it does not mean that you have IBC, but you should see a doctor right away. Tenderness, redness, warmth, and itching are also common symptoms of a breast infection or inflammation, such as mastitis if you’re pregnant or breastfeeding. Because these problems are much more common than IBC, your doctor might suspect infection at first as a cause and treat you with antibiotics.

Treatment with antibiotics may be a good first step, but if your symptoms don’t get better in 7 to 10 days, more tests need to be done to look for cancer. Let your doctor know if it doesn't help, especially if the symptoms get worse or the affected area gets larger. The possibility of IBC should be considered more strongly if you have these symptoms and are not pregnant or breastfeeding, or have been through menopause. Ask to see a specialist (like a breast surgeon) if you’re concerned.

IBC grows and spreads quickly, so the cancer may have already spread to nearby lymph nodes by the time symptoms are noticed. This spread can cause swollen lymph nodes under your arm or above your collar bone. If the diagnosis is delayed, the cancer can spread to distant sites.

How is inflammatory breast cancer diagnosed?

Imaging tests

If inflammatory breast cancer (IBC) is suspected, one or more of the following imaging tests may be done:

• Mammogram
• Breast ultrasound
• Breast MRI (magnetic resonance imaging) scan

Often a photo of the breast is taken to help record the amount of redness and swelling before starting treatment.

Biopsy

Inflammatory breast cancer is diagnosed by a biopsy, taking out a small piece of the breast tissue and looking at it in the lab. This might mean a punch biopsy of the breast skin that is abnormal. Your physical exam and other tests may show findings that are "suspicious for" IBC, but only a biopsy can tell for sure that it is cancer.

Tests on biopsy samples

The cancer cells in the biopsy will be examined in the lab to determine their grade.

They will also be tested for certain proteins that help decide which treatments will be helpful. Women whose breast cancer cells have hormone receptors are likely to benefit from treatment with hormone therapy drugs.

Cancer cells that make too much of a protein called HER2 or too many copies of the gene for that protein may be treated by certain drugs that target HER2.

In certain cases, other gene mutations (changes) or proteins might be tested for to see if specific drugs might be helpful.

Stages of inflammatory breast cancer

All inflammatory breast cancers start as stage III (T4dNXM0) since they involve the skin. If the cancer has spread outside the breast to distant parts of the body, it is stage IV.

For more information, read about breast cancer staging.

Survival rates for inflammatory breast cancer

Inflammatory breast cancer (IBC) tends to grow quickly, is more likely to have spread at the time it’s found, and is more likely to come back after treatment than most other types of breast cancer. Because of this, the survival rates are generally not as high as they are for other types of breast cancer.

Survival rates can give you an idea of what percentage of people with the same type and stage of cancer are still alive a certain amount of time (usually 5 years) after they were diagnosed. They can’t tell you how long you will live, but they may help give you a better understanding of how likely it is that your treatment will be successful.

Keep in mind that survival rates are estimates and are often based on previous outcomes of large numbers of people who had a specific cancer, but they can’t predict what will happen in any particular person’s case. These statistics can be confusing and may lead you to have more questions. Ask your doctor how these numbers may apply to you, as they are familiar with your situation.

What is a 5-year relative survival rate?

A relative survival rate compares women with the same type and stage of breast cancer to women in the overall population. For example, if the 5-year relative survival rate for a specific stage of breast cancer is 70%, it means that women who have that cancer are, on average, about 70% as likely as women who don’t have that cancer to live for at least 5 years after being diagnosed.

Where do these numbers come from?

The American Cancer Society relies on information from the Surveillance, Epidemiology, and End Results (SEER) database, maintained by the National Cancer Institute (NCI), to provide survival statistics for different types of cancer.

The SEER database tracks 5-year relative survival rates for breast cancer in the United States, based on how far the cancer has spread. The SEER database, however, does not group cancers by AJCC TNM stages (stage 1, stage 2, stage 3, etc.). Instead, it groups cancers into localized, regional, and distant stages:

• Localized: There is no sign that the cancer has spread outside of the breast.
• Regional: The cancer has spread outside the breast to nearby structures or lymph nodes.
• Distant: The cancer has spread to distant parts of the body such as the lungs, liver, or bones.

5-year relative survival rates for inflammatory breast cancer

These numbers are based on women diagnosed with IBC between 2012 and 2018.

(There is no localized SEER stage for IBC since it has already reached the skin when first diagnosed.)

Understanding the numbers

• Women now being diagnosed with inflammatory breast cancer may have a better outlook than these numbers show. Treatments improve over time, and these numbers are based on women who were diagnosed and treated at least 5 years earlier.
• These numbers apply only to the stage of the cancer when it is first diagnosed. They do not apply later on if the cancer grows, spreads, or comes back after treatment.
• These numbers don’t take everything into account. Survival rates are grouped based on how far the cancer has spread, but your age and overall health, how well the cancer responds to treatment, tumor grade, and other factors can also affect your outlook.

Treating inflammatory breast cancer

Inflammatory breast cancer (IBC) that has not spread outside the breast is stage III. In most cases, treatment is chemotherapy first to try to shrink the tumor, followed by surgery to remove the cancer. Radiation and often other treatments, like more chemotherapy or targeted drug therapy, are given after surgery. Because IBC is so aggressive, breast conserving surgery (lumpectomy) and sentinel lymph node biopsy are typically not part of the treatment.

IBC that has spread to other parts of the body (stage IV) may be treated with chemotherapy, hormone therapy, and/or targeted drugs.

For details, see Treatment of Inflammatory Breast Cancer.