Primary acquired melanosis of the conjunctiva: experience with 311 eyes

Trans Am Ophthalmol Soc. 2007:105:61-71; discussion 71-2.


Purpose: To evaluate clinical features and risks for transformation of conjunctival primary acquired melanosis (PAM) into melanoma.

Methods: Retrospective chart review and Kaplan-Meier estimates of times to PAM enlargement, recurrence, and transformation into melanoma.

Main outcome measures: PAM enlargement, recurrence, and transformation into melanoma.

Results: The mean patient age at diagnosis of PAM was 56 years; 62% were female and 96% Caucasian. The conjunctival quadrant(s) affected by PAM and its extent in clock hours were recorded. Initial management included observation in 62%, biopsy combined with cryotherapy in 34%, and other methods in 4%. Of PAM that was observed, Kaplan-Meier estimates at 10 years revealed PAM enlargement in 35% and transformation into melanoma in 12%. Of those that underwent incisional or excisional biopsy, 10-year estimates of PAM recurrence and transformation into melanoma were 58% and 11%, respectively. Progression to melanoma occurred in 0% of PAM without atypia, 0% of PAM with mild atypia, and 13% of PAM with severe atypia. Multivariable analysis revealed that the most significant factor for both PAM recurrence and progression to melanoma was extent of PAM in clock hours.

Conclusion: PAM without atypia or with mild atypia shows 0% progression into melanoma, whereas PAM with severe atypia shows progression into melanoma in 13%. The greater the extent of PAM in clock hours, the greater the risk for transformation into melanoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Biopsy
  • Conjunctivitis / complications*
  • Conjunctivitis / pathology
  • Cryotherapy
  • Eye Neoplasms / epidemiology*
  • Eye Neoplasms / pathology
  • Female
  • Functional Laterality
  • Humans
  • Male
  • Melanosis / etiology*
  • Melanosis / pathology
  • Melanosis / therapy
  • Middle Aged
  • Neoplasms / etiology
  • Neoplasms / pathology
  • Racial Groups
  • Retrospective Studies