Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer that occurs when cancer cells block the lymph vessels in the skin of the breast. According to the American Cancer Society (ACS), it accounts for only 1 to 5 percent of all cases of breast cancer.

IBC is different from other forms of breast cancer because it often doesn’t cause a lump or mass. This can mean that it might not show up on common breast cancer screening techniques like mammograms, making it more difficult to diagnose.

Because IBC is an aggressive type of cancer that can grow and spread quickly, it’s important to be able to recognize the signs of inflammatory breast cancer and speak with a doctor immediately if you notice changes in your breast.

IBC can progress rapidly within weeks or months. Because of this, receiving an early diagnosis is extremely important.

While you usually don’t develop a lump that’s characteristic of other breast cancers, you may have several of the following symptoms.

Breast discoloration

An early sign of IBC is discoloration of the breast, with a section of the breast appearing red, pink, or purple in color. Discoloration can impact a third or more of the breast, according to the National Cancer Institute.

The discoloration can look like a bruise, so you might shrug it off as nothing serious. But breast redness is a classic symptom of IBC. Don’t ignore unexplained bruising on your breast.

Breast pain

Due to the inflammatory nature of this particular cancer, your breast may look and feel different. For example, inflammation can cause your breast to feel warm to the touch. You may also have breast tenderness and pain.

Lying on your stomach may be uncomfortable. Depending on the severity of tenderness, wearing a bra may also be painful. In addition to pain and tenderness, IBC can cause persistent itching in the breast, especially around the nipple.

Skin dimpling

Another telltale sign of IBC is skin dimpling, or pitted skin. Dimpling — which can make the skin resemble the skin of an orange peel — is a concerning sign.

Change in nipple appearance

A change in the shape of the nipple is another possible early sign of IBC. Your nipple may become flat or retract inside the breast.

A pinch test can help determine if your nipples are flat or inverted. Place your thumb and index finger around your areola and gently squeeze. A normal nipple moves forward after pinching. A flat nipple doesn’t move forward or backward. A pinch causes an inverted nipple to retract into the breast.

Having flat or inverted nipples doesn’t necessarily mean you have IBC. These types of nipples are normal for some women and are no cause for concern. On the other hand, if your nipples change, speak with the doctor immediately.

Enlarged lymph nodes

IBC can cause enlarged lymph nodes. If you notice enlarged lymph nodes under your arm or above your collarbone, consult your doctor quickly.

Sudden change in breast size

IBC can change the appearance of the breasts. This change can occur suddenly. Because this cancer can cause inflammation and swelling, breast enlargement or thickness can occur.

The affected breast may appear noticeably larger than the other breast or feel heavy and hard.

If you’ve always had symmetrical breasts and you notice a sudden increase or decrease in the size of one breast, speak with your doctor to rule out IBC.

You may be familiar with the fact that there are different stages of breast cancer. These stages are used to reflect how far the cancer has progressed.

At the time of diagnosis, all cases of IBC are either at stage 3 or stage 4:

  • Stage 3. In stage 3 IBC, the cancer has spread to some of the tissues surrounding the breast. This can include nearby lymph nodes, the skin of the breast, and the tissues of the chest wall.
  • Stage 4. In stage 4 IBC, the cancer has spread to more distant areas of the body, such as the lungs, liver, or bones. This is called metastasis. According to the ACS, it’s estimated that IBC has metastasized in about 1 in 3 diagnoses.

Survival rates are used to give a general idea of the outlook for a specific type of cancer. A 5-year survival rate is typically used, which is the percentage of people with a certain type of cancer that are still alive 5 years after receiving their diagnosis.

The 5-year survival rates are reported based off of how far the cancer has spread. For IBC they are:

  • Regional (Stage 3): 56 percent
  • Distant (Stage 4): 19 percent
  • Overall: 41 percent

When looking at 5-year survival rates, it’s important to remember that they’re based off of a large number of people that have had IBC. Because of this, they can’t predict what will happen in each individual situation.

Because IBC can grow and spread very quickly, an early diagnosis is very important. The minimum diagnostic criteria for IBC include:

  • breast redness, swelling, dimpling, or warmth that comes on quickly, with or without a detectable lump or mass
  • redness that includes at least a third of the breast
  • symptoms that have lasted for no longer than 6 months
  • confirmation of the presence of cancer cells through a biopsy

Now let’s explore the diagnostic methods that can be used for IBC in a little more detail.

Mammogram

A mammogram is a screening method that uses X-rays to check for signs of breast cancer. During a mammogram, the breasts are compressed while the X-rays are taken. This helps to provide a clearer picture of the breast tissue.

Because IBC isn’t typically associated with a detectable lump, mammograms may not be able to detect it effectively. Additionally, since IBC can be associated with breast pain, obtaining the compression necessary for an accurate mammogram can be difficult.

Breast ultrasound

A breast ultrasound uses sound waves to create an image of breast tissue. A doctor can use these images to detect cancerous changes in the breast. A breast ultrasound can also be used to evaluate the surrounding lymph nodes.

Breast magnetic resonance imaging (MRI)

A breast MRI can also be used to create images of the breast tissue. Instead of the radiation that’s used in X-rays, MRI uses strong magnets and radio waves to generate images.

Breast MRI has the highest sensitivity at detecting cancerous breast changes. Because of this, it’s often used in the diagnosis of IBC.

Breast biopsy

During a breast biopsy, your doctor will remove a small sample of tissue from your breast. This will then be taken to a laboratory where it will be evaluated for signs of cancer. If cancer cells are detected in the biopsy, they can then be tested for:

  • Grade: The grade of a cancer is based off of how much the cells look like normal cells under a microscope. Cells with a higher grade appear more abnormal and are more likely to grow and spread quickly.
  • HER2: HER2 is a receptor that’s overexpressed on the surface of some cancer cells. Cancer that’s HER2-positive can grow and spread more rapidly, but can also be treated using drugs that specifically target the HER2 receptor. Many IBCs are HER2-positive.
  • Hormone receptors: Some breast cancer cells have receptors for estrogen and progesterone. These hormones can drive the growth of the cancer. While most IBCs are hormone-receptor negative, those that are positive may be treated using hormone therapy drugs.

After you’re diagnosed with IBC, the next step is for your doctor to stage the cancer. To do this, your doctor may order additional tests to see if the cancer has spread to nearby lymph nodes or other parts of the body. These can include things like:

Stage 3 inflammatory breast cancer treatment

Treatment for stage 3 IBC typically includes something called a multimodal approach, which involves a combination of three treatments:

  • Systemic therapies. Systemic therapies impact organs and tissues throughout your body and can help to shrink the cancer before surgery. Some examples of systemic therapies include:
    • chemotherapy, which uses strong drugs to kill cancer cells or slow their growth
    • hormone therapy, which can block the activity of hormone receptors on cancer cells
  • Surgery. Due to the aggressive nature of IBC, breast-conserving surgery (lumpectomy) isn’t typically recommended. Instead, surgery removes the affected breast and lymph nodes. This is called a modified radical mastectomy.
  • Radiation therapy. Radiation therapy uses high-power energy beams to destroy and stop the spread of cancerous cells. It’s used after surgery to help destroy any cancer cells that may remain. Additional systemic therapies may be used after surgery as well.

Stage 4 inflammatory breast cancer treatment

Cancer that’s spread to more distant areas of the body is typically treated using one or a combination of the systemic therapies mentioned above. These include:

  • chemotherapy
  • targeted therapy
  • hormone therapy

It’s unclear exactly what causes IBC to occur. In general, cancer develops due to genetic changes. These can happen due to a variety of factors, such as:

  • genetic changes inherited from your parents
  • errors that naturally occur during cell division
  • damage to DNA through environmental exposures

Sometimes mutations can happen in genes that are associated with cell growth and division. When this happens, cells can begin to grow and divide out of control.

In IBC, cells in the breast ducts or lobules begin to rapidly grow and divide. As cancer cells build up, they block the lymph vessels in the skin of the breast. These leads to the redness, swelling, and dimpling associated with IBC.

There are a few risk factors associated with developing IBC. These include:

  • Age. IBC typically occurs in younger women.
  • Weight. People that have overweight or obesity are more likely to develop IBC.
  • Race. Research shows that IBC occurs more frequently in Black women compared with white women.

Additional factors that require further evaluation include being a younger age at first pregnancy, smoking, and not breastfeeding.

Because IBC can grow and spread quickly, its outlook isn’t generally as good as other types of breast cancer. Early diagnosis and treatment are vital for improving outlook. That’s why it’s so important to see your doctor for sudden breast changes like redness, swelling, and dimpling.

Every individual is different. Remember that a variety of different factors can influence your outlook, such as age, overall health, and the stage of the cancer. Your doctor will work with you to develop a treatment plan that addresses your specific condition.

Additionally, research is ongoing into newer, more effective treatments for IBC. If you’ve been diagnosed with IBC, you may consider talking with your doctor about enrolling in a clinical trial.

A cancer diagnosis can be challenging. While undergoing treatment, be sure to seek support.

This could include:

  • joining a local support group for cancer patients and survivors
  • working with a therapist who helps cancer patients
  • confiding in family and friends

Find support from others who are living with breast cancer. Download Healthline’s free app here.

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