Metastatic cancer is not a single type of cancer, but a term used to describe any cancer that has spread from the area it started to other areas of the body. This can include spread to lymph nodes or more distant organs or bone. The area the cancer starts in is called the "primary site" and the area it spreads to is the site of metastasis. For example, colon cancer that has spread to the liver is metastatic, with the colon being the primary site and the liver being the site of metastasis. Cancer can spread from the original location by traveling through the lymph system or the blood stream.
A person may have a single metastatic tumor, which would be called a metastasis. If there is more than one metastatic tumor, it is called metastases (the plural of metastasis). Some other terms you may hear used to describe metastatic cancer include stage IV disease and advanced cancer.
When a cancer spreads to another area of the body, it still looks and acts like the original tumor. For example, a lung cancer that has spread to the brain is not brain cancer. It is lung cancer in the brain and when a sample of the tumor in the brain is examined under a microscope, it looks like lung cancer. This is important, because it drives treatment decisions – in this example, the brain tumor is treated with therapies that work for lung cancer, not for primary brain tumors.
All cancerous tumors have the potential to spread – this characteristic is what makes them cancer. Metastases from different primary cancers tend to be somewhat predictable, commonly spreading to the same areas. Remember that these areas are often not located close to the primary tumor.
Some cancers tend to spread "locally", or just in the area they started. Some examples of tumors that spread locally include: head & neck cancers, brain tumors, and esophageal cancer. "Blood cancers" (leukemia, multiple myeloma) may be considered to have spread when they are diagnosed because the cancerous cells can be found throughout the blood system and in the bone marrow. Lymphomas tend to spread through the lymph nodes, spleen and bone marrow. In some cases, blood cancers and lymphomas can spread to the brain or spinal cord.
The following table shows the most common sites of metastasis, excluding lymph nodes, for some of the common solid tumors:
|Cancer Type||Most Common Site of Metastasis|
|Bladder||Bone, liver, lung|
|Breast||Bone, brain, liver, lung|
|Colorectal||Liver, lung, peritoneum (abdominal cavity)|
|Kidney||Adrenal gland, bone, brain, liver, lung|
|Lung||Adrenal gland, bone, brain, liver, opposite lung|
|Melanoma||Bone, brain, liver, lung, skin/muscle|
|Ovary||Liver, lung, peritoneum (abdominal cavity)|
|Pancreas||Liver, lung, peritoneum (abdominal cavity)|
|Prostate||Adrenal gland, bone, liver, lung|
|Stomach||Liver, lung, peritoneum (abdominal cavity)|
|Thyroid||Bone, liver, lung|
|Uterus||Liver, lung, peritoneum (abdominal cavity), vagina|
Source: National Cancer Institute; Cancer.gov
How metastatic cancer affects treatment and prognosis varies greatly across cancer types. Even within metastases from one type of cancer there is variability. In some cancers, a single site of metastasis can be treated successfully with surgery or radiation. For some cancers, metastatic disease is routinely treated successfully, while for others the goals of treatment shift to assuring quality of life. It is important that you discuss your situation with your oncology providers to understand the goals of treatment and what you can expect over the course of the disease.
The treatments used for metastatic disease vary greatly as well. Your oncology team may provide multiple treatment options. You should weigh the potential risks and benefits of all your options; determine your treatment goals and ask how the treatments will affect your quality of life. You may want to seek additional opinions on your case. A second opinion is an educational session – it can present new treatment options or clarify those you have already heard about. Get the most out of a second opinion by coming prepared with questions, understanding the options that were already presented and asking why this oncology provider does or doesn't recommend the same. This is a time to call on your support people to help you take notes at your appointments and recall discussions after appointments.
A diagnosis of metastasis can mean different things to different people- each situation is unique. You may want to start aggressive treatment right away. Maybe this isn't your first go round with cancer. Perhaps you just aren't sure you want to go through more chemotherapy or surgery. There is no "right" way to respond. While surgery, chemotherapy or a clinical trial of a new medication may be the best option for some, others may feel that they don't want to pursue aggressive treatments. And that is okay. It may not be a decision family and friends will understand, but it is the patient's decision to make.
A diagnosis of metastatic cancer can make finding support harder. Friends and family may not know what to say or do for you and support groups with patients who are dealing with early stage cancer just don't seem to "fit". Reach out to trusted friends and family and tell them what you need. People who are unsure of how to help will appreciate being given a task – pick up records from my doctor to take for a second opinion, take my kids to soccer practice, etc. Make a list of tasks that people can help with and think about the skills of your support people, assigning tasks to people who are good for the job. For example, don't ask your friend who hates to cook to make a meal for your family, have them run an errand or provide transportation to an appointment.
Talk to your healthcare providers about finding support. Ask to see a social worker who can provide support and help you find resources for psychosocial and financial support. They can help you find a local support group or pair you with a "buddy" who has been through treatment. You are not in this alone!
The American Cancer Society – Advanced Cancer
CancerCare – Online support groups and counseling
Cancer Support Community – Local and online support and education
MetaCancer – Online support and education