This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer. It usually develops as a single, painless, bump on sun-exposed skin. The bump may be skin-colored or red-violet, and tends to grow rapidly over weeks to months. It may spread quickly to surrounding tissues, nearby lymph nodes, or more distant parts of the body. Factors associated with developing MCC include increasing age, fair skin, a history of extensive sun exposure, chronic immune suppression, and the Merkel cell polyomavirus. This virus has been detected in about 80% of people with MCC. Treatment may include surgery, radiation therapy, and/or chemotherapy. Treatment options and prognosis depend on the location(s) and size of the cancer, whether it has just been diagnosed or has come back (recurred), and how deeply it has grown into the skin.
For more information, visit GARD.