Cancer metastasis: What you need to know?

If the mention of cancer causes anxiety in the minds of certain people, then metastatic or advanced-stage cancers are their extreme. Let us look at what metastasis actually means. Tumours can be either benign or malignant. Benign tumours are those which remain confined to the tissue or the organ of its origin, and do not spread to other parts of the body. 

But, in some cases, the cells have a tendency to break away from the primary cancer tissue and travel via blood or lymph to other parts of the body to give rise to new tumours. These are called secondary tumours. Such cancers that spread are called metastatic cancers and the process through which they spread is called metastasis. Most metastatic cancers are advanced or stage IV cancers.

Since cancer can spread to any site inside the body, metastasis can occur by any of these three means:

• Cancer cells travel through the blood
• Cancer cells travel through lymph

While cancer cells can spread all through the body, some tissues and organs in the body are more prone to secondary metastatic cancers. Here are some examples:

• Breast cancer usually metastases to the lungs, liver, bones or the brain.
• Prostate cancer has a high tendency to spread to the bones.
• Lung cancer tends to spread to the bones, adrenal glands or the liver.
• Colon and rectal cancers usually spread to the lungs or the liver.

Considering the fact that metastasis occurs and cancer spreads to one or more vital organs, one would expect these advanced cases of cancer to show some specific signs and symptoms. However, unfortunately, this does not always happen. Many a time, even metastatic cancers are silent and symptomless. When a metastatic cancer begins to show symptoms, it is usually based on where the cancer is located.

What are the Signs and Symptoms of Metastatic Cancer?

Based on the location of metastatic cancer, the signs and symptoms can vary. 

• In the case of bone metastasis, symptoms include fragile bones that have a tendency to break without an injury or with minimal trauma, severe back pain and a feeling of weakness or numbness in the hands or legs. 
• In the case of cancer that spreads to the lungs, the patient may experience symptoms such as shortness of breath, blood in sputum and cough.
• Metastatic liver cancer can result in symptoms such as loss of appetite, abdominal pain and jaundice. 
• Similarly, cancer that metastasizes to the brain can result in serious effects such as frequent, painful headaches that refuse to go away, seizures, difficulty or inability to move the body, visual and auditory changes to name a few.

These signs and symptoms are very useful in the detection of metastatic cancer but since these overlap with other diseases and conditions, the doctor may not be able to immediately point out if his/her patient has metastatic cancer. 

However, if you have any of these symptoms, it is best to visit your doctor or an oncologist at the earliest. 

How is Metastatic Cancer Diagnosed?

There are no specific tests to diagnose metastatic cancer. If the healthcare provider suspects advanced-stage cancer, the patient is usually asked to undergo a series of tests that are expected to give a clearer picture of the patient’s condition.

Blood Tests

Most blood tests remain normal even when the cancer is metastasised and in advanced stages. While in some cases like the enzyme blood tests, elevated levels may indicate liver metastasis. 

Tumour Marker Tests

These tests are essentially blood tests that are useful especially after the diagnosis of metastatic cancer, in order to evaluate the progress of the disease. These tests are also applicable to a few cancers that have specific tumour markers. Many cancers do not have these specific markers and so, these tests cannot be used in such cases. 

Imaging Tests

These tests, as the name suggests, take images of the targeted organ where a tumour is suspected. Since these give us images, it becomes easy for the examiner and his team to understand the internal picture more clearly. The imaging tests prescribed for a particular metastatic cancer are dependent upon the symptoms of the patient and the suspected type of primary cancer. Some routinely used imaging tests are:

• Ultrasound: This imaging test is done when abdominal masses are suspected, especially in the liver. This test is also useful to detect any fluid in the abdomen and to diagnose cysts.
• CT Scan: Computerised Tomography Scan or a CT scan is usually done for the abdomen, head, neck, chest and pelvis. When a contrast dye is used in this imaging method, it is useful in the identification of a cancerous mass.
• MRI: This imaging test uses strong magnetic field and radio waves to create a detailed image of the organ. MRI may detect any cancerous cells or tissue mass that are affecting the brain, bones, spinal cord and vertebrae.
• Bone Scan: As the name suggests, this test is done to detect the presence of bone metastasis. A radioactive tracer is used that tends to attach itself to damaged bones and shows up as a ‘hotspot’ on the scan. This can be used by the doctor to conduct further tests that help identify the cancer and the extent of the damage.
• PET Scan: This imaging technique indicates areas of hypermetabolic activity. First, a substance made of sugar and a small amount of radioactive material (called tracers) are injected inside the body. As cancer cells tend to be more active than normal cells, they absorb the tracers. When the scan is performed, these hyper metabolically active cells light up. However, not all lit areas indicate cancer as this can be indicative of many other conditions as well.

How is Metastatic Cancer Treated?

After the diagnosis, “What next?”, is the most commonly asked question. Most people fear metastatic cancer because of the uncertainty around the condition, the progress of the disease, its treatment and the prognosis. But another important question that arises in their minds is: “Is metastatic cancer treatable?”

While some cases of metastatic cancers are treatable, in most other cases the advanced and viable treatment options are still under research. In such cases, treatment is mainly aimed at reducing the symptoms in the patient and improve his/her quality of life. The treatment of metastatic cancer depends upon:

• the origin of the primary cancer that has led to the metastatic cancer
• the extent of the spread of the cancer
• location of the cancer
• age and health of the patient
• patient’s choice of treatment.

Before beginning the treatment, the patient must ask his/her doctor about what the goal of the treatment is. The goals of the treatment can change as the treatment progresses, based on how the cancer responds to the treatment and how well the patient is coping. Some commonly used treatments that are routinely used in the management of metastatic cancers are:

• chemotherapy
• radiotherapy
• surgery
• immunotherapy.

Many a time, patients are advised to sign up for clinical trials but only a mere 3% to 5% of cancer patients will receive the chance to take part in these trials.

Coping with Metastatic Cancer

Being diagnosed with metastatic cancer can be very confusing for patients and their families.  In spite of the many advancements in both diagnosis and treatments, metastatic cancers are not always curable. In the case of metastatic cancers, the treatment includes ‘treating’ the cancer, but cannot always ‘cure’ it. But, this does not mean that there is no hope for patients with advanced-stage cancers, because treatment is usually aimed to cause one or more of the following effects:

• to reduce the effects of cancer
• to reduce the side-effects caused by treatment
• to improve the patient’s quality of life
• to increase the life expectancy of the patient.

Many a time, the phase of life after treatment for metastatic cancer in patients has been compared to living with chronic diseases like hypertension, type 2 diabetes, arthritis etc., even though the cancer has been treated to a large extent and the patients are living their life as normal. 

Coping with metastatic cancer involves multiple factors that influence the life of the patient as well as of his/her family members. These factors include emotional changes, lifestyle changes, psychological and physical challenges. 

The biggest hurdle that most people with metastatic cancer face is the inability to accept their condition and the uncertainty surrounding the disease. It is important for the patient as well as those around them to accept the situation, and take it in their stride, to win over the disease. Staying positive and realistic about the disease and the treatment is extremely important for patients with metastatic cancers.

If you or anyone close to you is diagnosed with metastatic cancer, it is always better to know what to expect from the treatment and other phases of managing your cancer journey.