To evaluate topical interferon alfa-2b (IFN-⍺2b) for the treatment of recalcitrant ocular surface squamous neoplasia (OSSN).

Prospective, noncomparative, interventional consecutive case series.

Ten patients with recalcitrant OSSN were treated with topical IFN-⍺2b (1 million IU/ml) four times a day until clinical resolution of the lesion or until the lesion appeared nonresponsive—that is, treatment failure. Progress was assessed by clinical examination and photographic records, with a minimum follow-up of six months.

Eight of 10 patients achieved clinical resolution from topical IFN-⍺2b treatment. One patient developed invasive squamous cell carcinoma and underwent exenteration. The other patient required further mitomycin C therapy to achieve clinical resolution. The mean duration to clinical resolution for the eight patients treated with IFN-⍺2b was 21.9 weeks (range six to 59 weeks). There have been no recurrences for any of the nine patients during follow-up (mean 55.0 weeks; range 26 to 84 weeks).

Topical IFN-⍺2b is an important treatment modality for recalcitrant OSSN; it avoids the risks of further limbal stem cell destruction from other agents and surgical excision. If invasive disease is diagnosed at any stage, topical therapy is contraindicated, necessitating surgical excision.