PRAME immunohistochemistry is useful in the evaluation of conjunctival melanomas, nevi, and primary acquired melanosis.

PRAME was useful for distinguishing melanoma and its probable precursors from benign conjunctival melanocytic proliferations in our cohort. The data alert us to two diagnostic pitfalls in nevi: scattered, PRAME-positive intraepithelial melanocytes and cytoplasmic PRAME staining in type-A melanocytes and melanophages. Larger scale investigations are warranted to further substantiate these promising findings.