Metastatic lesions are malignant, or cancerous, tumors that have spread from their original location to other parts of the body. Related medical terms that might be used interchangeably include late-stage cancer, advanced cancer, or metastatic disease. In general, metastatic lesions are considered to be incurable, although treatment is often available to control the spread of cancerous cells and potentially increase the individual's life expectancy.
Medically speaking, a lesion can refer to any abnormal change in a body tissue or organ resulting from injury or disease. In cancer terminology, lesion is another term for tumor. Metastasis is the term for the spread of cancer beyond its originating site in the body. Thus, metastatic lesions are cancerous tumors that are found in locations apart from the original starting point of the primary tumor. Metastatic tumors occur when cells from the primary tumor break off and travel to distant parts of the body via the lymph system. Alternately, cells from the original tumor could seed into new tumors at adjacent organs or tissues.
Metastatic disease is sometimes called late-stage cancer. This term refers to the medical classification of cancer as being in stage III, when cancer cells are found in lymph nodes near the original tumor, or in stage IV, when cancer cells have traveled far beyond the primary tumor site to distant parts of the body. Metastatic lesions are most commonly found in the brain, lungs, liver, or bones. An individual with metastatic cancer might or might not experience any symptoms, and the symptoms could be related to the area where metastasized cells have relocated. For example, a person whose cancer has spread to the brain could experience neurological symptoms such as seizures or headaches.
Once metastatic lesions are present in the body, the individual's cancer will be considered incurable. This means it is no longer possible to target every existing cancer cell with available treatments. In this case, the goal of treatment becomes slowing the growth of tumors to maintain the highest possible quality of life and potentially extend the individual's life expectancy. In some cases, people with metastatic lesions can live for a number of years with appropriate treatment for symptom management.
A variety of treatments are available for advanced cancer. Some potential options include the surgical or cryosurgical removal of cancerous lesions, radiation therapy, biological therapy — also known as immunotherapy — to boost immune system response, chemotherapy, and hormone therapy. Clinical trials, in which the individual participates in experimental new treatments for specific types of cancer, are available in some areas. Individuals might also choose to use complementary or integrative therapies in addition to medical treatment.