title: Multiple primary melanomas.
abstract: BACKGROUND
  The diagnosis of primary melanoma increases the risk of additional primary melanomas.
  
  
  OBJECTIVE
  We characterize the subgroup of patients with multiple melanomas.
  
  
  METHODS
  We reviewed the melanoma database.
  
  
  RESULTS
  Sixty patients with multiple primary melanomas were identified. Twelve (20%) experienced melanomas in the same regional location, 43 (72%) in different locations, and 5 (8%) in both the same and different locations (> 2 melanomas). Eighteen (30%) were diagnosed concurrently with multiple melanomas, 38 (63%) subsequently, and 4 (7%) concurrently and subsequently (>2 melanomas). Forty-two percent of subsequent melanomas occurred within 3 years of the initial lesion diagnosis, 9 (17%) between 3 and 7 years, and 22 (42%) after more than 7 years. Subsequent melanomas were thinner in 70% of cases (P = .05). The mean age at first melanoma diagnosis was 38 and 59 years, respectively, for those with and without dysplastic nevi (P < .001).
  
  
  CONCLUSIONS
  In patients with multiple melanomas, subsequent melanomas often occur in different regional locations several years after diagnosis of the initial lesion.
authors.affiliation: University of Michigan Medical Center and Comprehensive Cancer Center, Ann Arbor, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Johnson
authors.forename: T
authors.initials: T
authors.lastname: Hamilton
authors.forename: L
authors.initials: L
authors.lastname: Lowe
mesh_terms: D017668:Age of Onset; D016208:Databases, Factual / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008545:Melanoma / Q000453:epidemiology*; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology*; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology*; D013997:Time Factors