Breast Cancer: Where is It Most Likely to Spread?

Patient Expert
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By its very nature, most invasive breast cancer tries to move from its initial site in your breast or armpit to elsewhere in your body. Where is it most likely to show up next? And what warning signals should you watch for?

“Metastatic” is a word that might be vaguely familiar to the general population. But to breast cancer survivors, it’s the kiss of death – quite literally.

What is metastatic breast cancer?

Metastatic breast cancer – cancer that’s spread beyond the breast and underarm lymph nodes to other parts of the body – is incurable. Advances in treatment have significantly prolonged the amount of time a woman with metastatic (stage 4) breast cancer can live. But, barring accidental death or some other fatal health issue, a woman with metastatic breast cancer knows that in the end she’ll die from it.

About 30 to 40 percent of women with breast cancer whose disease is advanced enough to receive chemotherapy eventually develop “mets” – metastases, cancer that’s settled somewhere else in the body. Given that this is a fairly significant number, it’s important that survivors be aware of the warning signs of a recurrence.

When cancer leaves the breast, about 88 percent of the time it’ll reach the underarm lymph nodes. Thankfully, it’s usually caught and stopped right there. Cancerous and surrounding nodes are removed, and that’s the end of it. A woman whose cancer has spread to her lymph nodes isn’t considered to have metastatic breast cancer.

It’s only when the cancer travels farther – a “distant recurrence” – that it becomes a killer.

Bones

The most common destination for metastatic breast cancer is to the bones. Nearly 20 percent of women with stage 4 breast cancer have it in their bones.

What are the common symptoms of bone metastasis to watch out for?

  • Unexpected fractures. Cancer makes bones brittle. You may fracture a rib simply with a firm hug, or hard laughter.
  • Pain. Severe and recurrent backache is common, though bone pain can occur in the shoulders, knees, hips, and other parts of the body, as well.

Liver and lungs

About 12 percent of breast cancer metastases happen in the liver, and 12 percent in the lungs. Common symptoms of lung metastases include the following:

  • Chest pain.
  • Chronic cough.

If cancer has spread to your liver, you may notice the following:

  • A yellow tint to your skin or the whites of your eyes (jaundice).
  • Itchy skin, or an unexplained rash that doesn’t respond to treatment.
  • Abdominal pain and bloating, sometimes accompanied by nausea and vomiting.

Skin

About 5 percent of breast cancer metastases happen in the skin. (While inflammatory breast cancer is also cancer that involves the skin, it’s not considered metastatic breast cancer.) Symptoms are often noticed close to the site of the original tumor: for instance, along the line of a mastectomy scar. The chest is the most common places for a skin metastasis, though back, abdomen, and scalp can also be affected.

Things to watch out for:

  • Small, hard nodules, usually skin colored or slightly reddened. These can range from barely noticeable to quite large.
  • Raised, firm, scar-like patches of skin.

Brain

While it’s what many women fear most, less than 2 percent of breast cancer metastases occur in the brain. Symptoms mimic that of brain cancer, and may include the following:

  • Persistent headache.
  • Nausea and vomiting.
  • Vision disturbances and seizures.
  • Personality changes.

Other areas

Finally, about 5 percent of breast cancer metastases occur in assorted other parts of the body beyond those listed above. A dear friend of mine died from a metastasis to her small intestine, one that went undiagnosed for quite some time simply because it was so very rare.

Do respond, but don’t panic

Are you experiencing any of these symptoms? If so, call your doctor; but don’t panic. Many of these changes in health can have other, benign causes.

For instance, a chronic cough might be the result of radiation damage to your lungs that, while annoying, isn’t dangerous. Or headache: I once had a headache every day for seven weeks; a brain scan couldn’t detect anything wrong, and it eventually went away.

Your takeaway? All survivors, but especially those whose initial cancer was serious enough to warrant chemotherapy, need to be aware of persistent and unexplained health changes – and take them seriously.

Are you worried about a pain, illness, or physical change that just doesn’t disappear? Call your oncologist. You’re not being “silly;” simply responsible for your health – and your life.

See more helpful articles:

A Guide to Breast Cancer Symptoms

When It Spreads: Breast Cancer Metastasis, Part 1

Do You REALLY Need That Test?

Sources

"Metastatic Breast Cancer: The National Breast Cancer Foundation." www.nationalbreastcancer.org. Accessed September 12, 2015.

"Recurrent and Metastatic Breast Cancer." Breastcancer.org. September 9, 2015. Accessed September 12, 2015.

Vogel, Wendy. "Metastatic Breast Cancer Overview." Metastatic Breast Cancer Overview. Metastatic Breast Cancer Overview. June 1, 2013. Accessed September 12, 2015.