The term metastasis is one we often hear connected to cancer, though sometimes it’s not clear precisely what this term means. When a doctor says that cancer has ‘metastasized,’ this is referring to cancer spreading beyond its original location or body part. Other terms that mean the same as metastasis commonly used by doctors may include ‘stage four cancer,’ as well a ‘metastatic cancer.’ However, it’s essential to confirm with your doctor exactly what they are referring to, and where cancer has spread to also.

Metastasis is an umbrella term for cancer that has spread to any other area of the body. Once cancer has spread, the patient is then at a higher risk. Metastasis can occur to patients with any form of cancer at different stages of treatment. However, it’s important to note that not every case will be the same. Some types of cancer are more likely to spread, and other forms may grow less quickly.

How metastasis happens

Metastases – the plural of metastasis – most commonly happens as a result of cancer cells that break off from the primary cancerous tumor. When this occurs, these cells often enter the lymphatic system or bloodstream and are then carried around the body. This is how a patient with one form of cancer may end up with cancer in an entirely different part of their body. Once cells have been separated from the primary tumor, they can settle and form new tumors; leading to the spread of cancer.

As well as cases where cancer cells enter the bloodstream or lymphatic system, these cells may also break off and grow in nearby areas. For example, a patient with cancer in the abdominal area may have spread into their liver or lungs. Certain types of cancer are more prone to spreading than others, and certain forms of different cancers may be more likely to spread also.

Where cancer can spread to

Cancer can spread to virtually every part of the body from its source. However, certain types of cancer tend to have specific patterns when it comes to where they are most likely to spread. Breast cancer, for example, is most likely to spread to the bones, lungs, chest, liver, or brain, whereas prostate cancer is most known for spreading to the bones.

However, there is no ‘set rule’ for where cancer can spread. We only know the more likely places that cancer can metastasize to. It’s possible but less frequent that cancer can spread to the muscle, skin, or other un-attached organs in the body.

Is metastasis different from the cancer I had previously?

Metastasized cancer is still the same form of cancer with which a patient is first diagnosed. This is because the source of cancer that has spread is from that original location. For example, lung cancer that then spreads to the bones is called metastatic lung cancer, instead of bone cancer. The treatment for cancer that has metastasized is the same as the treatment targeting cancer in its original location.

How is metastasis diagnosed?

Typically, metastasis is diagnosed during follow-up testing once a patient has been diagnosed with cancer. Once a patient is under the care of a hospital for cancer treatment, they will receive a care plan, including regular check-ups. During this time, doctors can check for metastases. However, in other cases where cancer is diagnosed later down the time, or where cancer has metastasized early on, the patient may be diagnosed as such during initial testing. This testing is used to ‘stage’ cancer, which is where the staging system comes from when referring to the severity of cancers.

Treatment for metastasis

The treatment for metastasized cancer can vary significantly according to several factors. Including where primary cancer started, the amount the cancer has spread, and even the age and health of the individual. At this point, the patient’s personal treatment decisions also come into play. Treatment for metastases often has little difference from traditional medicine.

The two primary forms of treatment are whole-body therapies, such as chemotherapy, or targeting therapy, such as radiation or surgery. Again, this will depend upon the opinion of the doctor treating the patient. While it is possible to cure metastatic cancer, in the majority of cases, the purpose of treatment is to slow growth and reduce active symptoms.

Metastatic cancer doesn’t necessarily mean an immediate fatal diagnosis, but it can be considered far more deadly than many other forms of cancer. In many cases, palliative care forms a later part of treatment plans for metastasized cancer.