titer in the blood to the Merkel cell polyomavirus oncoprotein can be used as a treatment response biomarker in people that have detectable antibodies at the time of diagnosis. Epidemiology Merkel cell carcinoma occurs most often in Caucasians between 60 and 80 years of age. Its incidence is about twice as high in males as in females. It is a rare type of skin cancer, with a 2013 incidence of only 0.7 per 100,000 persons in the U.S. As of 2005, roughly 2,500 new cases of MCC are diagnosed each year in the United States, as compared to around 60,000 new cases of malignant melanoma and over 1 million new cases of nonmelanoma skin cancer. Similar to melanoma, the incidence of MCC in the US is increasing rapidly. Worldwide, MCC is most commonly found in regions with increased sun exposure. Australia is the country with the highest incidence of MCC but has a lower incidence of MCV-positive MCC than observed in other countries. Since 2006, it has been known that other primary cancers increase the risk of MCC significantly, especially in those with the prior multiple myeloma, chronic lymphocytic leukemia, and malignant melanoma. Immunosuppression including HIV infection or immunosuppressant therapy following organ transplant or for autoimmune disease can also increase the odds of developing MCC. History Friedrich Sigmund Merkel (1845–1919) was a German anatomist and histopathologist who first described the Tastzellen (touch cells) in the skin in 1875. In 1878 the term Merkel cell was coined by the anatomist Robert Bonnet (1851–1921). Merkel-cell carcinoma was first described in 1972 by Cyril Toker. He reported five cases of 'trabecular carcinoma of the skin'. Notable patients Avigdor Arikha – Paris-based painter and art historian David Brudnoy – Boston talk radio host Al Copeland – New Orleans entrepreneur, powerboat racer Al Davis – Principal owner of the Oakland Raiders of the National Football League Ed Derwinski – U.S. Representative from Illinois and 1st Secretary of Veterans Affairs Leonard Hirshan – Showbusiness agent and manager. Max Perutz – Nobel Prize–winning chemist Lindsay Thompson – Former Premier of Victoria, Australia Joe Zawinul – Jazz-fusion keyboardist and composer John Fitch – Race car driver and road safety pioneer Carl Mundy – 30th Commandant of the United States Marine Corps Geoffrey Penwill Parsons – Pianist Maria Bueno – Tennis player References External links Epidermal nevi, neoplasms, and cysts Integumentary neoplasia Rare cancers