Abstract

Purpose: To report on topical treatment with interferon (IFN) alfa-2a for conjunctival primary acquired melanosis (PAM) with atypia.

Design: A retrospective interventional case series.

Subjects: Patients diagnosed with PAM with atypia.

Methods: Patients received topical IFN α-2a, IFN α-2b, or pegylated IFN α-2a. Treatment duration, response, adverse effects, and progression-free survival (PFS) were assessed. Data was collected from the medical records of the patients with institutional review board approval.

Main outcome measures: Response to treatment and PFS.

Results: Treatment duration ranged from 1 to 10 months, with an average follow-up of 10.48 years. A complete clinical response was observed in 11 of 12 patients (93%) after an average of 5.1 months of treatment. The average PFS was 52.5 months (4.3 years), with only one patient experiencing recurrence after 13 months. Treatment was well tolerated; five patients reported mild adverse effects, including dry eye, redness, and blurred vision. Two patients experienced more severe side effects, leading to treatment discontinuation. No limbal stem cell damage was observed in patients treated with IFN alone.

Conclusions: Topical interferon alpha-2a is safe and effective for treating PAM with atypia and for PAM with atypia surrounding conjunctival melanoma that arises from PAM with atypia, with high response rates and little to no toxicity. Its similarity to IFN α-2b and safety profile make IFN α-2a a good alternative. Further large-scale, controlled studies are needed to validate these findings and their role in clinical practice.