title: Merkel cell carcinoma: a population-based study on mortality and the association with other cancers.
abstract: BACKGROUND
  Few population-based epidemiological data are available on Merkel cell carcinoma (MCC), a rare lethal non-melanoma skin cancer. We analysed multiple-cause-of-death records to describe MCC mortality and trends and the association with other primary cancers.
  
  
  METHODS
  We reviewed all 6,713,059 death certificates in Italy (1995-2006) to identify those mentioning MCC. We evaluated the association with other primary cancers by calculating the ratio of observed to expected deaths, using a standardized mortality ratio (SMR)-like analysis. We also evaluated the geographic distribution of deaths.
  
  
  RESULTS
  We identified 351 death certificates with the mention of MCC. The age-adjusted mortality was 0.031/100,000, with a significant trend of increase and a slight north-south gradient. There was a significant deficit for solid cancers (SMR = 0.15) and a non-significant excess for lymphohematopoietic malignancies (SMR = 1.62). There were significant excesses for chronic lymphocytic leukemia (SMR = 4.07) and Waldenström's macroglobulinemia (SMR = 27.2) and a non-significant excess for chronic myeloid leukemia (SMR = 5.12).
  
  
  CONCLUSIONS
  The increase in MCC mortality reflects the incidence trend in the literature. The association with chronic lymphocytic leukemia confirms the importance of immunologic factors in MCC. Regarding Waldenström's macroglobulinemia, an association with MCC has never been reported.
authors.affiliation: Dipartimento di Scienze Radiologiche, Oncologiche e Anatomo-Patologiche, Università La Sapienza, Viale Regina Elena 324, Rome, Italy. valeria.ascoli@uniroma1.it
authors.forename: Valeria
authors.initials: V
authors.lastname: Ascoli
authors.forename: Giada
authors.initials: G
authors.lastname: Minelli
authors.forename: Mark
authors.initials: M
authors.lastname: Kanieff
authors.forename: Luisa
authors.initials: L
authors.lastname: Frova
authors.forename: Susanna
authors.initials: S
authors.lastname: Conti
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000401:mortality*; D015331:Cohort Studies; D003644:Death Certificates; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D009369:Neoplasms / Q000401:mortality; D012878:Skin Neoplasms / Q000401:mortality*