Primary Acquired Melanosis (PAM)

Primary Acquired Melanosis (PAM)
  • Typically develops in middle-aged or elderly white patients.

Clinical Features

  • Almost always unilateral
  • Uni- or multifocal, flat, indistinct areas of conjunctival pigmentation
  • Commonly involves the inferior or superior fornices
  • May remain stable over years, become smaller, undergo color changes or malignant transformation
  • Work up: multiple biopsies are sometimes required to define the cytological status of the lesions.


  • Regular follow-up with photographic documentation.
  • Local excision with or without extensive cryotherapy should be performed if the lesion becomes thicker and demonstrates invasive nodular formation.