What Is Pleural Metastasis in Breast Cancer Recurrence?

Written by Julie Marks
Medically Reviewed by Shruthi N, MD on September 21, 2025
6 min read

Breast cancer can go away for a while and then show up again. It can also spread to different areas of your body when it comes back. Sometimes, breast cancer returns and spreads to the pleura, the lining around your lungs. Doctors call this pleural metastasis in breast cancer recurrence.

Pleural metastasis, a type of breast cancer recurrence, happens when treatment doesn’t kill all the cancerous cells in your breast.

“Breast cancer cells can travel through the bloodstream or lymphatic system to other parts of the body,” says Ilana Schlam, MD, a breast medical oncologist and clinical researcher at Dana-Farber Cancer Institute in Boston.

When leftover cells escape from the original tumor, they settle in another part of your body. In pleural metastasis, they spread to the outside covering of your lungs.

How common is it?

In general, breast cancer recurrence is less common than other types of cancer recurrence. But the chances of your cancer coming back depend on many factors, from the type and stage of the cancer to the treatment. For example, the chances of your cancer coming back may be higher if you have triple-negative (hormone-receptor negative, HER2-negative) breast cancer vs. hormone-receptor positive (HR+) breast cancer.

But it’s hard to know exactly how many people have pleural metastases. That’s because some studies group cancer that’s spread to the lungs and cancer that’s spread to the pleura in the same category.

Case reports show that pleural metastasis is more common in the first few years after your breast cancer diagnosis. It seems to be much less common after 10-12 years of being cancer-free.

In general, the risk of your breast cancer coming back may be higher if you have a more aggressive type of breast cancer, such as inflammatory breast cancer. Being diagnosed with a later stage of breast cancer may affect your risk, too. For example, breast cancer may be more likely to come back if you were diagnosed with locally advanced breast cancer vs. early breast cancer.

But we need more research to understand what may make you more likely to get pleural metastasis.

If cancer cells have moved to the lining of your lungs, you may notice symptoms such as:

  • Shortness of breath
  • Chest pain or discomfort
  • A cough that doesn’t go away
  • Wheezing
  • Coughing up blood
  • Feeling tired or weak
  • Losing weight without trying to
  • Not feeling hungry 
  • Generally not feeling well (called “malaise”)

If you have shortness of breath, chest pain, or a cough that doesn’t get better, see your doctor right away, says Neelima Vidula, MD, a breast medical oncologist at Massachusetts General Hospital in Boston.

If you have symptoms, your doctor may order a test to check on your cancer. But health care providers may spot pleural metastasis by chance.

“Some patients with metastatic breast cancer may be asymptomatic but have a restaging scan to follow response to treatment that shows lung metastases,” Vidula says.

Your doctor might order these tests to see if you have pleural metastasis:

  • Chest X-ray, a picture of your chest that includes your lungs, heart, and bones
  • Imaging tests, which may include an MRI, CT, ultrasound, or PET scan, to show doctors what’s happening inside your body
  • A pleural biopsy, in which doctors remove tissue from the lining of your lungs to check for cancer cells
  • A pleural needle biopsy, in which a needle is used to remove the tissue from the lining of your lungs
  • Thoracentesis, in which doctors take out fluid from around your lungs to check for cancer cells

Your treatment options will likely depend on your overall health, how advanced your cancer is, and your tumor type. Your care team might combine different methods to best treat it.

“Treatment focuses on both controlling the cancer and improving symptoms,” Schlam says. “The best plan is personalized, based on the type of breast cancer, symptoms, and the patient’s overall health.”

Even though pleural metastasis means the cancer has spread, there are options to help you feel better and breathe easier.

Some possible treatments for pleural metastasis include:

Whole-body therapies. These may include chemotherapy, targeted therapy (drugs that target specific features on cancer cells), hormone therapy (a treatment for tumors that test positive for hormones), or immunotherapy (medicines that use your own immune system to fight cancer).

Treatments for any fluid around your lungs. If too much fluid builds up around your lungs, your doctor may need to drain it. This can help you breathe better. Or you might need radiation therapy to shrink your tumors. In some cases, doctors do a procedure that binds your lung lining to your chest wall so that fluid won’t come back.

Supportive care. You may get other treatments to make you more comfortable. Pain management approaches, oxygen therapy, and physical therapy are some that could help.

“Patients generally remain on a treatment until disease progression occurs or the development of unacceptable side effects,” Vidula says.

Often, doctors use a team approach to treat pleural metastasis. That means your cancer specialist (medical oncologist) might treat the cancer itself. A special lung doctor (a pulmonologist or thoracic surgeon) typically does the procedures to remove fluid from around your lungs.

When breast cancer spreads to the lining around your lungs, it can cause complications, which are secondary problems. Some possible issues include:

  • Pleural effusion: When fluid builds up in the pleural space, causing chest pain, cough, and shortness of breath
  • Trouble breathing: Since tumors that press on your lungs can make it hard to breathe
  • Continued spread of cancer

Pleural metastasis symptoms and your treatments’ side effects can make daily activities difficult, too.

Your outlook with pleural metastases will depend on many factors, including: 

  • Your overall health
  • How you respond to treatment
  • Your age
  • The type of tumor you have

If your cancer has spread to the lining of your lungs, it’s considered stage IV. Even though there’s no cure for metastatic breast cancer, there are many treatments available, and the outlook can vary a lot. Some people live for months, while others live for several years.

Less than 1 in 4 people live for more than five years after this diagnosis. But these numbers don’t tell the whole story for every person.

“It’s important to know that you are not alone and that there are effective treatments to help control both the cancer and its symptoms,” Schlam says.

There’s no way to completely prevent cancer from spreading to the pleura, Schlam says. Doctors still don’t know exactly why breast cancer returns in some people but not in others.

But there are some steps you can take to lower the chances of your breast cancer coming back, such as getting effective treatment. Surgery that removes the entire tumor, along with chemo, radiation, targeted therapy, or immunotherapy, can kill cancer cells so they don’t have a chance to spread.

Routine exams may help your doctor spot cancer before it spreads. 

“It’s also important for patients who have been treated for early-stage breast cancer to see their oncologist and physicians regularly for monitoring,” Vidula says.