Abstract
Purpose :
Topical treatment of high grade conjunctival intraepithelial neoplasia (CIN) or primary acquired melanosis (PAM) with atypia with mitomycin C (MMC) is very effective, but some patients have multiple recurrences and multiple courses of MMC result in limbal stem cell (LSC) deficiency. Alternatives for MMC for CIN include 5-Fluorouracil and interferon-α2b (IFNa2b). Lack of availability of IFNa2b led us to try IFNa2a. The purpose of this work is to report the first patients treated with IFNa2a for CIN or PAM and compare the results relative to treatment with IFNa2b or MMC.
Methods :
A retrospective analysis of a cohort of patients treated for recurrent CIN/PAM with atypia with IFNa2a (3 milU/0.5ml) that was administered topically from the needleless syringe twice daily for 3-6 months.
Results :
Six patients (3 women) were diagnosed with recurrent PAM (4) or recurrent CIN (2). Clinical remission was reached after 2 months irrespective of their diagnosis, but treatment was continued for 6 months in the first 4 patients and 3 months for the last two. Follow-up ranged from 2-12 months. No local recurrence was noted. Side effects included slight irritation and flu-like symptoms (mainly malaise). The first two patients were switched from IFNa2b to IFNa2a and reported that the only difference was slightly more eye irritation with IFNa2a vs. IFNa2b. Clinical remission of pigmentation was faster with IFNa2a than with IFNa2b.
Conclusions :
IFNa2b is known to be effective for CIN, to work slower than MMC, but less damaging to the corneal limbal stem cells. IFNa2a appears effective for both CIN and PAM, with minimal tolerable side effects. These initial results indicate that IFNa2a can safely replace IFNa2b in the treatment of CIN and PAM.
This is a 2020 ARVO Annual Meeting abstract.