When cancer spreads from the primary, or original, site to distant parts of the body, it’s called metastatic disease. It’s important to understand that not all advanced cancers are metastatic, and not all metastatic diseases are the same. Some may be more treatable than others. It’s also helpful to know what to expect from treatment, how long it might last, and what other things might happen with your health over time.
Some people develop metastases for the first time when they are diagnosed with a cancer in an organ such as the lung or the liver. For other people, the spread happens after they have already finished treatment for a non-metastatic cancer. When cancer that has spread to other parts of the body is detected, it is usually found during routine follow-up exams with your doctor or as a result of specific tests, such as blood work and CT scans. The new tumors are then referred to as metastatic cancer or stage 4 cancer.
Most cancers that have spread to the lungs can be cured by removing the affected part of the lung. However, most of the time when cancer spreads to the lungs it is because of another condition, such as leukemia or lymphoma. Cancer that has spread to the bones is most often seen in the spine (vertebrae), ribs, and long bones, including the pelvis, hip bone, and breastbone. Bone metastases are also common in cancers that start in the colon, kidney, and thyroid.
Cancer cells can spread to distant parts of the body in three ways: through the bloodstream, from one bone to another, or directly from the primary site to other sites. A metastasis is a collection of cancer cells that grows into tumors, or masses. It can also refer to a single tumor that has grown from a metastatic mass.
The goals of treatment for metastatic cancer depend on the type and location of the primary cancer, where the cancer has spread, and how it responds to other treatments. In general, doctors try to cure the primary cancer and prevent it from coming back. In some cases, the cancer will never be cured, but it can be controlled so that symptoms are relieved and the patient can live longer.
New methods for treating metastatic cancer are being developed all the time. Your doctor can talk to you about clinical trials that are being conducted for your type of cancer. Many of the treatments that are now considered standard for treating metastatic cancer began with clinical trials led by doctors at MSK. Visit the Metastatic Cancer Research page on this website to learn more about current research and ongoing treatment studies. It’s important to tell your doctor what is most important to you, as the goal of treatment can vary between people.
