What is metastasis?

Metastasis is a process wherein cancer spreads from one part of the body to the other, affecting one or more organs. This may also be known as ‘secondary’ cancer, and is a late stage, meaning metastatic cancer has a lower possibility of being cured.

How does metastasis happen?

Cancer can spread from the primary cancer site to other areas of the body through the lymphatic system or through the bloodstream. Cancer cells spread from one organ to another in this way, and tumours then form in other parts of the body. This does not create a new cancer, but rather is a metastasised form of the original cancer, e.g breast cancer which spreads to the lung does not become lung cancer, but is metastatic breast cancer.

What are the symptoms of metastatic cancer?

Metastatic cancer does not always show symptoms. If are present, the symptoms of metastatic cancer depend on where the cancer has spread to and how large the tumours are. Symptoms related to metastatic cancer may include:

Bone fractures and pain (when the cancer has spread to the bone).
Headaches, seizures, and dizziness (when the cancer has spread to the brain).
Being short of breath (when cancer has spread to the lungs).
Jaundice (yellowing of skin and eyes) or swelling in the abdomen (when cancer has spread to the liver).

There are some general symptoms and signs of metastatic cancer, which include:

Weakness
Tiredness
Lack/loss of energy
Pain
Shortness of breath
Unintentional weight loss

How is metastatic cancer diagnosed?

Metastatic cancer is normally discovered at a follow-up appointment for another type of cancer. The way it is discovered usually depends on the original cancer the patient has.

It can be diagnosed through:

biopsy
MRI scan
CT scan
ultrasound
PET scan
bone scan
blood tests
tumour markers

Where does the cancer spread?

Cancer can spread to any part of the body, however, certain types are more likely to spread to particular parts of the body than others. The bone, liver and lung are the most common places where cancer spreads.

These are the parts of the body where metastasis is likely to spread, based on the type of cancer.

Bladder cancer: bone, liver and lung.
Breast cancer: bone, brain, liver and lung.
Colon cancer: liver, lung and peritoneum
Kidney cancer: adrenal gland, bone, brain, liver, lung
Melanoma (skin cancer): bone, brain, liver, lung, skin, muscle
Lung cancer: adrenal gland, bone, brain, liver, other lung
Ovarian cancer: liver, lung, peritoneum
Pancreatic cancer: liver, lung, peritoneum
Prostate cancer: adrenal gland, bone, liver, lung
Rectal cancer: liver, lung, peritoneum
Stomach cancer: liver, lung, peritoneum
Thyroid cancer: bone, liver, lung
Uterine (womb) cancer: bone, liver, lung, peritoneum, vagina

Is metastasis always terminal?

Sometimes, metastasis cancer can be cured, depending on the situation. In some cases, patients may even live for months or years after the diagnosis of a metastatic cancer. However, unfortunately, more often than not, metastasis cannot be cured. That being said, treatment can reduce the rapid nature of the growth and reduce symptoms.

Can metastasis be treated?

Once cancer has started spreading, it is difficult to then control it and treat it. Some metastatic cancers can be treated, but sadly most cannot. The mainstay of treatment in cases where the cancer cannot be cured is to slow the growth of the cancer or to reduce or relieve the symptoms caused by it. Treatment for metastatic cancer depends on the primary cancer form and where the cancer has spread. The efficacy of treatment is also dependent on several factors, such as:

The type of cancer
Where the cancer is located and where it has spread
How rapidly the cancer is growing
How much cancer there is
The specific treatment and how cancer responds to it

Coping with metastatic cancer

If you are diagnosed with metastatic cancer, then you will want to consider your options in terms of the course of action to take. Some questions you may wish to consider are:

What are the different treatment options
How effective each treatment is
If the potential benefits outweigh the potential side effects
What would be the goal of treatment
What will happen if you do not want treatment

There is a lot of support available to help if you have been diagnosed with metastatic cancer. You should maintain clear communication with the care team in order to understand the illness. If you feel that treatment isn’t the best option for you, you may wish to consider palliative care, which aims to improve cancer symptoms and improve quality of life. Palliative care can significantly improve quality of life for patients and the care team will help to relieve patients’ symptoms, as well as providing emotional support.

Is metastasis preventable?

The risk of secondary cancer developing depends on many factors, such as the type of cancer and the age the patient develops the cancer. While secondary cancer can develop, it is important to note that the risk is relatively small. It is not yet possible to entirely prevent metastasis.

Which specialist treats metastatic cancer?

Cancer is often dealt with by various specialists as different specialties are involved in different areas of the treatment – for example, if surgery is necessary, a surgeon will be involved in treatment. However, the doctor who assesses, diagnoses and treats cancer is an oncologist.