Risk factors for melanoma incidence in prospective follow-up. The importance of atypical (dysplastic) nevi

Arch Dermatol. 1994 Aug;130(8):1002-7.


Background and design: Assessment of melanoma risk factors can help identify individuals at greatest risk for melanoma. Previous studies were retrospective case-control or prospective without control groups. A prospective group of 3889 employees without previous melanoma or family history of multiple melanoma at the Lawrence Livermore (Calif) National Laboratory were examined as part of a melanoma screening program. Their subsequent incidence of melanoma in relationship to potential melanoma risk factors, which were recorded at the first examination, was determined.

Results: Nine invasive melanomas developed after initial examination among the studied population over an 8-year period with an average follow-up of 5 years. The presence of an easily recognized pattern of definite clinically atypical (dysplastic) nevi was present in 7% of employees and was associated with a cumulative melanoma risk of 1.9%. It was the strongest risk factor, with a relative risk of 47 compared with the 0.04% cumulative melanoma risk in the 64% of employees with no atypical (dysplastic) moles (chi 2 for equal risk, P = 7 x 10(-8). Significant, but less marked associations with melanoma risk were found for the total number of moles and for a history of many moles in other family members, with a maximal relative risk of 11.6 and 10.4, respectively.

Conclusion: A small subgroup of the population with easily recognizable definite atypical (dysplastic) nevi have a marked increased risk of melanoma. Smaller significant melanoma risks were found for a total number of moles and a family history of many moles.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Aged
  • Biopsy
  • Dysplastic Nevus Syndrome / epidemiology*
  • Dysplastic Nevus Syndrome / genetics
  • Dysplastic Nevus Syndrome / pathology
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Male
  • Melanoma / epidemiology*
  • Melanoma / genetics
  • Melanoma / pathology
  • Phenotype
  • Prospective Studies
  • Risk Factors
  • Skin Neoplasms / epidemiology*
  • Skin Neoplasms / genetics
  • Skin Neoplasms / pathology