Epidemiology of primary Merkel cell carcinoma in the United States.
BACKGROUND
Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer.


OBJECTIVE
We sought to describe primary MCC incidence trends, epidemiology, and predictors of survival.


METHODS
The population covered by the Surveillance, Epidemiology, and End Results Program was analyzed as a prospective cohort. We measured age-adjusted incidence rates (per 100,000 person-years) and effect of age, anatomic site, and stage on survival.


RESULTS
Incidence was higher in males (0.34) than in females (0.17). Cases (n = 1034) occurred mostly in whites (94%), in people older than 65 years (76%), and at the head (48%). The 5-year relative survival was 75%, 59%, and 25% for localized, regional, and distant MCC, respectively. Female sex, limb presentation, localized disease, and younger age were positive predictors of survival.


CONCLUSIONS
The highest incidence of MCC was observed in whites, males, and in people older than 65 years. Only 49% of cases were reported as localized. Better survival was associated with limb localization, early-stage disease, younger age, and female sex.
Agelli
Maria
M
National Cancer Institute, Bethesda, MD, USA. ma215e@nih.gov
Clegg
Limin X
LX
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000453:epidemiology*; D002648:Child; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018426:SEER Program; D012878:Skin Neoplasms / Q000453:epidemiology*; D015996:Survival Rate; D014481:United States / Q000453:epidemiology