title: Epidemiology of nonkeratinocytic skin cancers among persons with AIDS in the United States.
abstract: OBJECTIVE
  Immunosuppression may increase risk for some skin cancers. We evaluated skin cancer epidemiology among persons with AIDS.
  
  
  METHODS
  We linked data from population-based US AIDS and cancer registries to evaluate risk of nonkeratinocytic skin cancers (melanoma, Merkel cell carcinoma, and appendageal carcinomas, including sebaceous carcinoma) in 497 142 persons with AIDS.
  
  
  METHODS
  Standardized incidence ratios (SIRs) were calculated to relate skin cancer risk to that in the general population. We used logistic regression to compare risk according to demographic factors, CD4 cell count, and a geographic index of ultraviolet radiation exposure.
  
  
  RESULTS
  From 60 months before to 60 months after AIDS onset, persons with AIDS had elevated risks of melanoma (SIR = 1.3, 95% confidence interval 1.1-1.4, n = 292 cases) and, more strongly, of Merkel cell carcinoma (SIR = 11, 95% confidence interval 6.3-17, n = 17) and sebaceous carcinoma (SIR = 8.1, 95% confidence interval 3.2-17, n = 7). Risk for appendageal carcinomas increased with progressive time relative to AIDS onset (P trend = 0.03). Risk of these skin cancers was higher in non-Hispanic whites than other racial/ethnic groups, and melanoma risk was highest among men who have sex with men. Melanoma risk was unrelated to CD4 cell count at AIDS onset (P = 0.32). Risks for melanoma and appendageal carcinomas rose with increasing ultraviolet radiation exposure (P trend <10 and P trend = 10, respectively).
  
  
  CONCLUSIONS
  Among persons with AIDS, there is a modest excess risk of melanoma, which is not strongly related to immunosuppression and may relate to ultraviolet radiation exposure. In contrast, the greatly increased risks for Merkel cell and sebaceous carcinoma suggest an etiologic role for immunosuppression.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland 20892, USA.
authors.forename: Emilie
authors.initials: E
authors.lastname: Lanoy
authors.forename: Graça M
authors.initials: GM
authors.lastname: Dores
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Madeleine
authors.forename: Jorge R
authors.initials: JR
authors.lastname: Toro
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Fraumeni
authors.forename: Eric A
authors.initials: EA
authors.lastname: Engels
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications / Q000453:epidemiology* / Q000276:immunology / Q000635:transmission; D018266:Adenocarcinoma, Sebaceous / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D000293:Adolescent; D000328:Adult; D018791:CD4 Lymphocyte Count; D015266:Carcinoma, Merkel Cell / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D002648:Child; D002675:Child, Preschool; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008545:Melanoma / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D008875:Middle Aged; D012878:Skin Neoplasms / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D014481:United States / Q000453:epidemiology; D055815:Young Adult