If you have red, swollen breasts, it’s a sign that something is wrong. Two things that can cause these symptoms are inflammatory breast cancer and a breast infection.

Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer. IBC accounts for 1 to 5 percent of all breast cancers in the United States. It’s a very serious disease.

A noncancerous infection of the breast tissue is called mastitis. A breast infection can be troublesome, but it often clears up fairly quickly. It usually occurs in women who are breastfeeding.

It’s important to learn the signs and symptoms of each, when to see your doctor, and what treatments are available.

Some symptoms of IBC are quite similar to those of a breast infection. This similarity can lead to misdiagnosis or delayed diagnosis of IBC.

Both IBC and breast infection can cause redness of the skin, breast tenderness, and swelling. But there are also some differences.

The symptoms of IBC tend to differ from those of other forms of breast cancer, and there’s usually no obvious lump in people who have IBC.

The symptoms of IBC can include the following:

  • The skin on your breast can turn dark and appear bruised. This will usually involve a large area of the breast.
  • The skin on your breast might also look dimpled like an orange peel. This dimpling is caused by a buildup of fluid in the breast that’s due to cancer cells blocking the lymph vessels. This prevents the fluid from draining normally.
  • You may also notice swollen lymph nodes near your collarbone or under your arm.
  • Your breasts may tend to swell quickly.
  • Your breasts may feel heavy.
  • You may feel a burning sensation in your breasts.

If you have a breast infection, you’ll probably feel sick. Other possible symptoms include:

  • redness or purple tint of the breast
  • swelling of the breast
  • pain in the breast
  • a painful, fluid-filled mass in the breast
  • a fever
  • chills
  • nausea
  • vomiting
  • a yellowish discharge from the nipple

A breast infection usually affects only one breast, and it can make nursing painful.

Any woman can get a breast infection, but it’s more likely to happen when you’re breastfeeding. Cracked nipples can allow bacteria to enter your body. You’re also at higher risk for an infection if you have blocked milk ducts.

Inflammatory breast cancer isn’t common. The median age at diagnosis is 57. Black women have a higher risk than white women. You’re also at higher risk if you’re obese.

Your doctor can usually make a diagnosis of a breast infection based on your symptoms and a physical examination.

IBC can be difficult to diagnose. This type of cancer grows quickly. It can start between routine screening mammograms. If IBC is suspected, a diagnostic mammogram should be performed. An ultrasound of the breast and nearby lymph nodes may be necessary.

A biopsy of the suspicious breast tissue can help your doctor determine if it’s cancerous. Pathology tests are also used to check hormone receptor status. Most of the time, IBC is hormone receptor-negative. This means the cancer cells aren’t encouraged to grow in response to the presence of specific hormones.

In addition, the pathologist will find out if the cancer cells have human epidermal growth factor receptor 2 (HER2). Your doctor will use this information to help create the best treatment plan for you.

Imaging tests can help your doctor determine if the cancer has spread anywhere else. These tests can include:

  • X-rays
  • bone scans
  • positron emission tomography (PET) scans
  • CT scans

IBC is always diagnosed at a locally advanced stage, which means at stage 3 or 4 because of how the breast cancer cells grow into a nearby secondary organ, the skin.

Treatment for a breast infection

The primary treatment for a breast infection is antibiotics. You’ll usually need to take the medication for 10 to 14 days. You can also use mild over-the-counter (OTC) pain relievers.

Be sure to drink plenty of fluids and get adequate rest to fight the infection. If breastfeeding is a problem, your doctor or lactation consultant can help you adjust your technique. After a couple of weeks, your infection should be cleared up.

Treatment for inflammatory breast cancer

Treatment for IBC usually takes a combination of several therapies. It all depends on the specifics of your cancer, age, and overall health.

Chemotherapy can help shrink the tumor. It can also kill cancer cells throughout your body. You’ll need surgery to remove the tumor, and most likely the entire breast and nearby lymph nodes. Radiation therapy can kill any cells left behind after surgery.

If the biopsy found that the cancer is HER2-positive, HER2 therapy can be part of your treatment plan. If your cancer is estrogen-positive, hormone therapy can be used. These are called targeted therapies.

You should see your doctor right away if you have a red, swollen, and painful breast. You may have a breast infection or IBC. If you develop these symptoms and you’re breastfeeding, it’s most likely an infection. If you aren’t breastfeeding and develop these symptoms you may need additional testing to rule out IBC.

A breast infection can interfere with breastfeeding, but IBC is rare and can be life-threatening. Both conditions should be treated as quickly as possible.

If you are diagnosed with a breast infection, your doctor will probably give you antibiotics. You should start to feel better within a few days. If you don’t, report it to your doctor. It may be that you need to try a different antibiotic. It could also be that you don’t have an infection and need additional tests.