Metastatic Neoplasm

Metastatic neoplasm is cancer that has spread from where it first started to other parts of the body. Nearly all cancers can spread, but whether they do depends on several factors. While most metastatic cancers cannot be cured, treatments can help manage symptoms and improve quality of life.

Table of contents

• What is metastatic neoplasm?
• Other names
• How cancer spreads
• Common sites of spread
• Symptoms
• What causes metastasis?
• How is it diagnosed?
• Treatment options
• Living with metastatic cancer

What is metastatic neoplasm?

Metastatic neoplasm is cancer that spreads from the place where it first started to other areas of the body^[1]. The original cancer is called the primary tumor, which is where the cancer originated. When cancer spreads to other parts of the body, it is called metastatic cancer^[2].

Nearly all cancers have the potential to spread to other parts of the body. But whether they do depends on several factors, including the type, size, and location of the primary tumor^[1]. The cancer cells that have spread have the same characteristics as the primary cancer, not the characteristics of the organ where they have spread^[2].

For example, breast cancer that spreads to the liver is still called metastatic breast cancer, not liver cancer. This is because the cancer cells found in the liver originated in the breast and would resemble breast cancer cells^[9]. Healthcare providers treat metastatic cancer based on where it started, not where it has spread^[1].

Most cancer-associated deaths occur due to metastasis, not the primary tumor^[5]. Unlike primary tumors, which can often be cured with local treatments such as surgery and radiation, metastatic cancer is a systemic disease, meaning it affects multiple organs throughout the body^[5].

Other names

Metastatic neoplasm is also known by several other names^[1][3]:

• Metastatic cancer
• Stage IV (4) cancer
• Secondary cancer
• Advanced cancer
• Cancer with mets (or mets cancer)
• Metastases (more than one cancerous tumor)
• Metastasis (one cancerous tumor)

How cancer spreads

Cancer cells can spread to other parts of the body in three main ways^[1][3]:

Direct extension or invasion means that the primary tumor grows directly into the tissues or structures around it. For example, prostate cancer can grow into the bladder^[3].

Lymphatic system spread occurs when cancer cells break away from the primary tumor and travel through the lymphatic system. The lymphatic system is a group of tissues and organs that make and store cells that fight infection and disease. Cancer cells can move through the lymphatic system to reach another part of the body^[3].

Bloodstream spread, also called hematogenous spread, happens when cancer cells break away from the primary tumor, enter the blood, and travel to a new place in the body^[3].

Cancer cells spread through the body in a series of steps. These steps include growing into nearby normal tissue, moving through the walls of nearby lymph nodes or blood vessels, traveling through the lymphatic system and bloodstream to other parts of the body, stopping in small blood vessels at a distant location, invading the blood vessel walls, moving into the surrounding tissue, and growing in this tissue until a tiny tumor forms^[2].

The immune system usually attacks and destroys cancer cells that travel through the lymphatic system or blood. But sometimes cancer cells survive and settle in another area of the body, where they form a new tumor^[3]. To survive and grow in the new place, the tumor must form its own blood supply, a process called angiogenesis^[3].

Most of the time, spreading cancer cells die at some point during this process. But as long as conditions are favorable for the cancer cells at every step, some of them are able to form new tumors in other parts of the body^[2]. Metastatic cancer cells can also remain inactive at a distant site for many years before they begin to grow again, if at all^[2].

Common sites of spread

Where cancer spreads during metastasis depends on the location of the primary tumor^[1]. Cancer can spread to almost any part of the body, although different types of cancer are more likely to spread to certain areas than others^[2].

Some of the most common sites where cancer spreads include^[1][2]:

• Adrenal glands
• Bones
• Brain
• Liver
• Lungs
• Lymph nodes
• Peritoneum (the membrane that lines the abdomen)

Some common cancers and their typical sites of spread include breast cancer, which often spreads to bone, brain, liver, and lung; colorectal cancer, which commonly spreads to liver, lung, and peritoneum; and lung cancer, which may spread to the adrenal gland, bone, brain, liver, and other parts of the lung^[2].

Symptoms

Metastatic cancer doesn’t always cause symptoms. Cancer cells can grow and spread gradually over many months or years. In some instances, it’s possible to have Stage IV cancer and not know it^[1].

General symptoms of metastatic cancer may include^[1][2]:

• Extreme fatigue
• Night sweats
• Unexplained weight loss

Some signs of metastatic cancer depend on the location of the primary tumor and where the cancer cells have spread. Depending on the type of metastasis, symptoms might include^[1][2]:

• Bloating, swollen belly, decreased appetite, getting full quickly, or jaundice (common in liver metastases)
• Bone pain or fractures (common in bone metastases)
• Dizziness, headaches, and seizures (common in brain metastases)
• Shortness of breath (common in lung metastases)

What causes metastasis?

Metastasis happens when cancer cells break off from the original tumor and spread to other parts of the body. These cancer cells can travel through the bloodstream or lymph vessels^[1].

Many factors can trigger metastasis, including^[1]:

• A weakened immune system
• Hypoxia (a lack of oxygen in the tissues)
• Lactic acidosis (a buildup of lactic acid in the blood)
• Autophagy (a type of cell death)

Whether or not a cancer spreads depends on many factors, including the type of cancer, how fast the primary cancer is growing, the size and location of the primary cancer, how long the primary cancer has been in the body, and whether cancer treatments were used and how well they worked^[3].

How is it diagnosed?

Some people already have metastatic cancer at the time of their diagnosis. In these cases, a healthcare provider usually detects metastases during initial testing^[1].

Other people develop metastases after completing treatment for non-metastatic cancer. During routine follow-ups, a healthcare provider checks for signs of recurrence, which is cancer that comes back after treatment^[1].

Your healthcare provider may use one or more of the following tests to diagnose metastatic cancer^[1]:

• Biopsy (removal of tissue for examination)
• Blood tests
• Bone scans
• CT (computed tomography) scans
• MRI (magnetic resonance imaging) scans
• PET (positron emission tomography) scans
• Tumor marker-based tests
• Ultrasound
• X-rays

Treatment options

Healthcare providers can treat metastatic cancer based on where it started, not where it has spread^[1]. Most people with metastatic cancer are treated with systemic therapies, which are treatments that work throughout the entire body^[16].

Doctors can’t cure most metastatic cancers, but treatment can help manage symptoms and improve quality of life^[1]. Treatment options may include^[13][15][16]:

Chemotherapy involves the use of drugs to kill cancer cells throughout the body. Chemotherapy can shrink tumors, relieve symptoms, and prolong life^[17]. The choice of chemotherapy drugs depends on the type and location of the cancer.

Hormone therapy is used for cancers that are driven by hormones, such as some breast and prostate cancers. This treatment works by blocking the body’s natural hormones that help cancer cells grow^[15].

Targeted therapy uses drugs that target specific molecules involved in cancer cell growth and survival. By blocking these molecules, targeted therapy can slow or stop cancer progression^[17].

Immunotherapy boosts the body’s immune system to recognize and attack cancer cells. Immunotherapy has shown promising results in treating various cancers, including melanoma, lung cancer, and certain types of lymphoma^[17].

Radiation therapy uses high-energy beams to kill cancer cells. It can be used to treat metastatic tumors in specific areas of the body. A specialized type called stereotactic body radiation therapy (SBRT) uses image-guided techniques to target high doses of radiation to metastatic tumors with extreme precision^[13].

Surgery may be used to remove metastatic tumors, especially if they are causing symptoms or if there are only a few metastases^[13].

In some cases, particularly when cancer has spread to only one or a few sites, a condition called oligometastatic cancer, more aggressive treatment combining local therapies like surgery or radiation with systemic therapies may be used with the goal of long-term disease control^[8][11].

Living with metastatic cancer

Living with metastatic cancer presents unique challenges. After diagnosis, people may experience a range of emotions including fear, anger, sadness, and feeling overwhelmed^[18][19].

It’s important to give yourself time to process the diagnosis and not pressure yourself to make decisions right away^[18]. Many people find it helpful to:

• Build a support system of family, friends, healthcare providers, and others living with metastatic cancer
• Seek professional counseling or join support groups
• Communicate openly with your medical team about your priorities and preferences
• Focus on quality of life and managing symptoms
• Engage in activities that bring meaning and joy
• Practice stress management techniques like meditation or yoga
• Maintain physical activity as able
• Eat a nutritious diet

Fear of recurrence or progression is common among people living with metastatic cancer. This fear can intensify around the time of regular scans and appointments, a feeling sometimes called “scanxiety”^[19]. Talking with your healthcare team about these fears, learning about your specific type of cancer, and connecting with others who understand can help.

Many people with metastatic cancer are living longer than was once possible due to advances in treatment. Some view their cancer as a chronic disease that requires ongoing management, similar to diabetes or heart disease^[19][21].

While a metastatic cancer diagnosis is serious, it doesn’t mean you cannot aim for the best possible quality of life. Focus on achievable daily goals and try not to let the cancer keep you from moving forward, enjoying life, and spending time with loved ones^[22][25].