Considering the immune system dysfunction in unifocal orbital eosinophilic granuloma (EG); possible complications of surgery, intralesional steroid, and radiotherapy; immunomodulatory and cytoreductive effects of interferon Alpha 2b (IFN-α2b); and its safety profile in treatment of ocular surface neoplasia, intralesional IFN-α2b was firstly commenced in treatment of EG.

A report of a series of 3 consecutive patients (8, 25, and 43 years old males) with EG from 2007 to 2014 who were treated with intralesional IFN-α2b. After confirmation of diagnosis on histological examination, 3 intralesional injections of IFN-α2b (1.5 million units/ 0.5 ml) were given every other day. Iran University Eye Research Center IRB committee approved the study.

Cases 1 and 3 showed a rapid response with no recurrence in 86 and 29 months follow up. Case 2, however, required a second course of injection 2 months after the first one due to a partial response to the first injections with no recurrence at last follow up (57 months). Transient flulike symptom was observed after the injections in case 2 and 3.

This is the first report on the efficacy and safety of intralesional IFN-α2b injection in patients with EG. Long term follow up showed no side effects and recurrence.