What Is a Metastatic Carcinoma?

Metastatic carcinoma refers to a particular type of cancer that grows in an area of the body distant from the primary cancer site. Carcinoma is the name given to cancer that arises in the epithelial tissue of the skin or the lining of internal organs. It is the most commonly occurring type of cancer in the human body. Although a metastatic carcinoma can occur anywhere, the areas most often affected are the liver, lungs, brain, and bones.

All cancer begins in the cells. The cells in the human body constantly grow and divide, forming new cells to take the place of dead cells. On occasion, this process goes awry, and the body makes new cells when they are not needed and old cells refuse to stop functioning. These extra cells can then form a solid mass, called a tumor, and if a tumor is tested as malignant, it is considered cancerous. If a malignant tumor occurs on the epithelial tissue of the skin or on the lining surrounding an internal organ, it is labeled as a carcinoma.

Cells, at times, can separate from a carcinoma and get into a person’s bloodstream or lymphatic system. Once this happens, the problematic cells can then travel to and grow elsewhere in the body distant from the point of origin of the carcinoma. If this occurs, the cancer is said to have metastasized, and the person then has what is known as a metastatic carcinoma.

Generally, this type of carcinoma is named for the area of the primary cancer, even when it metastasizes in another area. For instance, if the carcinoma originally developed on the lining of the lungs and is later found to have grown in the brain, the carcinoma that is found on the brain is considered metastatic lung carcinoma rather than brain cancer. The status of a cancerous mass as a metastatic carcinoma is usually determined by examining the cells under a microscope and using certain markers, or antigens, to determine the location of its origin.

Although a metastatic carcinoma can occur just about anywhere, most often, doctors diagnose it in the liver, lungs, brain, and bones. Certain types of carcinomas tend to metastasize into particular areas. For instance, lung cancer will often find its way to the brain and bones, while colon cancer tends to metastasize into the liver. Further, metastatic carcinomas can metastasize into more than one area of the body. Treatment options will vary but become more difficult once the carcinoma has metastasized.