title: Multiple primary melanomas.
abstract: BACKGROUND
  Patients with clinically diagnosed dysplastic nevi or a family history of melanoma with or without histologically diagnosed dysplastic nevi seem to be at higher risk for the development of multiple melanomas.
  
  
  OBJECTIVE
  Our purpose was to determine which factors increased the risk for the development of subsequent melanomas.
  
  
  METHODS
  This was a retrospective study in 56 patients with 157 melanomas.
  
  
  RESULTS
  Early age at onset (58.9%), clinically diagnosed dysplastic nevi (82.0%), a histologically diagnosed dysplastic nevus (64%), family history of clinically diagnosed dysplastic nevi (70.8%) or melanoma (64.7%) and a histologically diagnosed dysplastic nevus in combination with a family history of melanoma (48%) were found in a high percentage of patients. The mean age at diagnosis was 38.2 years. The mean interval between the first and second melanoma was 34.3 months. Of the second melanomas, 76.8% developed in a different anatomic region from the first melanomas. The mean tumor thickness (Breslow) decreased from 1.11 mm for the first melanomas to 0.90 mm for the second melanomas.
  
  
  CONCLUSIONS
  The results suggest that genetic factors might be involved in a certain subset of patients in whom melanomas develop early and successively.
authors.affiliation: Department of Dermatology and Pathology, Leiden University Medical Center, The Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: Stam-Posthuma
authors.forename: C
authors.initials: C
authors.lastname: van Duinen
authors.forename: E
authors.initials: E
authors.lastname: Scheffer
authors.forename: J
authors.initials: J
authors.lastname: Vink
authors.forename: W
authors.initials: W
authors.lastname: Bergman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004416:Dysplastic Nevus Syndrome / Q000150:complications* / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D008875:Middle Aged; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000209:etiology* / Q000235:genetics / Q000473:pathology