Abstract
Purpose :
To examine the long-term outcomes and recurrence rates of off-label Interferon-alpha 2b (IFN-α2b) treatment for ocular surface squamous neoplasia (OSSN).
Methods :
A retrospective, observational study was conducted by reviewing medical records of patients with OSSN who received IFN-α2b eye drops (1 million IU/ml) or injections (10 million IU/ml) after diagnosis between 2007-2020. Data were collected from clinic letters, operative notes, and histology reports. Statistical analyses were performed using the R statistical package. The main outcome measure was time to tumor recurrence. Time-to event curves were produced with the Kaplan-Meier method.
Results :
47 eyes (43 patients) received IFN-α2b eye drops 4x/day after biopsies or surgical excisions, and 3 eyes received subconjunctival injections in addition. 37 eyes were diagnosed as conjunctival intraepithelial neoplasia (CIN) and 10 as squamous cell carcinoma (SCC). Mean patient age was 69 years (range 46-87 years). More patients were male (n=27) than female (n=16). IFN-α2b eye drops were used for a median of 3 months, during the follow-up period (median 30 months, IQR 12-52 months) tumor recurrence occurred in 11 eyes (9 CIN, 2 SCC). Median time to recurrence was 68 months in patients with CIN and 76 months in patients with SCC. Recurrence was noticed an average of 10 months (IQR 5-37 months) after IFN-α2b treatment was stopped. The most commonly reported side effects were foreign body sensation and viral symptoms, particularly after subconjunctival injections, but overall IFN-α2b was well-tolerated and treatment did not have to be discontinued.
Conclusions :
Our results align with previous studies in showing that IFN-α2b is well-tolerated, but the rate of tumor recurrences (n=11, 23%) and a prolonged median recurrence-free time suggest that long-term follow-up is important in patients with OSSN.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.