Breast cancer is cancer that begins in the breast. According to the American Cancer SocietyTrusted Source, breast cancer is the most common cancer in women in the United States, making up about 30 percent of all new cancer diagnoses in women.
While breast cancer begins in the breast, it can also spread to other areas. When a cancer spreads to more distant tissues from where it started, it’s called metastatic cancer. Research estimated that about 155,000 womenTrusted Source were living with metastatic breast cancer in the United States in 2017.
Below, we’ll explore more about metastatic breast cancer and the most common areas where it’s detected. Then, we’ll cover how this type of cancer is diagnosed and treated, plus steps you can take to prevent it.
What is metastatic cancer?
Metastatic cancer is cancer that’s spread to a different part of the body than where it originated. You may also see metastatic cancer referred to as stage 4 cancer.
In some cases, the cancer may have already spread by the time of initial diagnosis. Other times, the cancer may spread after the initial treatment. For example, a person who has been treated for early-stage breast cancer may later be diagnosed with metastatic breast cancer.
Metastasis can occur with almost every type of cancer and is considered advanced-stage cancer. Cancer metastasis may occur months to years after initial breast cancer treatment.
There’s also a type of metastatic cancer called oligometastatic cancer. This is where there’s only a few small areas of metastatic cancer. Because this type of metastatic cancer is only found in a few locations, researchers hope it will be more treatableTrusted Source.
What’s the difference between metastatic and recurring breast cancer?
Recurrent cancer is cancer that comes back after your initial treatment. This can happen when treatment doesn’t completely destroy all of the cancer cells in a tumor. As time passes, these remaining cancer cells can begin to grow into detectable tumors.
Like metastasis, recurrence can happen with almost every type of cancer. As we’ll see below, some types of recurrent cancer can happen distantly and therefore also fall under the umbrella of metastatic cancer.
Breast cancer may recur locally, regionally, or distantly:
Local recurring breast cancer occurs when a new tumor develops in the breast that was originally affected. If the breast has been removed, the tumor may grow in the chest wall or nearby skin.
Regional recurring breast cancer happens in the same region as the original cancer. In the case of breast cancer, this may be the lymph nodes above the collarbone or in the armpit.
Distant recurring breast cancer happens when cancer cells travel to a different part of the body. This new location is far away from the original cancer. When cancer recurs distantly, it’s considered metastatic cancer.
Where are the common sites that breast cancer metastasizes to?
According to the National Cancer InstituteTrusted Source, the most common metastasis locations for breast cancer are the:
bones
lungs
liver
brain
The frequency that breast cancer metastasizes to each of these sites can vary based off of the population studied. A 2017 studyTrusted Source in Scientific Reports included a group of 4,932 people with metastatic breast cancer. Researchers determined the metastatic site (or sites) for each person and found that:
65.1 percent of people had bone metastases
31.4 percent of people had lung metastases
26 percent of people had liver metastases
8.8 percent of people had brain metastases
Additionally, 33.5 percent of people had metastasis in multiple organs. The most common combination of sites were the bones and lungs.
Bone metastasis
Bones are often the first site that breast cancer metastasizes to. Any bone can be affected, although the most common ones include the:
spine
pelvis
ribs
long bones in the arms and legs
Initially, it can be hard to tell the difference between a bone metastasis and the effects of much more common conditions like arthritis or a strain. However, pain from a bone metastasis eventually becomes persistent and doesn’t go away with rest.
Lung metastasis
It’s possible to have a lung metastasis and not know it, as symptoms aren’t always present. In fact, your doctor may first find a lung metastasis during a follow-up scan after your initial treatment.
When symptoms are present, it’s easy to initially mistake them from those of a pre-existing lung condition or a respiratory infection like the common cold or the flu. However, symptoms will continue to linger long after a respiratory infection should have cleared.
Liver metastasis
Similar to a lung metastasis, breast cancer that’s spread to the liver may not cause noticeable symptoms at first. Because of this, it may first be detected when routine blood tests show elevated liver enzymes, which can be a sign of liver damage.
Brain metastasis
In many people with a brain metastasis, breast cancer has already spread to other areas of the body. According to this 2016 study, the spread of breast cancer to the brain is more common with aggressive types of breast cancer like triple-negative or HER2-positive breast cancer.
You must be logged in to post a comment.