In the present study, the effectiveness of topical chemotherapy for the primary treatment of ocular surface squamous neoplasia (OSSN) was evaluated.

We enrolled 10 patients (10 eyes) diagnosed with OSSN who received both clinical examination and anterior segment optical coherence tomography (AS-OCT) imaging. The patients were administered topical 0.02% mitomycin-C (MMC) 4 times/day in the affected eye. The patients with MMC-resistant OSSN received topical 1% 5-fluorouracil (5-FU) 4 times/day. AS-OCT imaging was performed before and after the treatment. Clinical examination and AS-OCT were used to monitor the efficacy of topical chemotherapy, recurrence and side effects.

The mean age of the 10 patients (8 males, 2 females) was 76.7 years. The proportion of complete remission resulting from topical treatment with MMC was 80.0% (8 eyes) and 20.0% (2 eyes) when 5-FU was changed to MMC. The average duration of complete remission was 4.3 weeks and the average duration of no recurrence was 17.5 months. The epithelial thickness of the lesions, measured using AS-OCT, significantly decreased from 315.0 µm (pretreatment) to 105.3 µm (after complete remission). Additionally, the epithelial lesion appeared normal after treatment. The most common side effect was conjunctival hyperemia (60.0%, 6 eyes), followed by ocular allergy (30.0%, 3 eyes), superficial punctate keratitis (30.0%, 3 eyes) and corneal erosion (20%, 2 eyes). No serious complications were reported.

Topical chemotherapy is as effective and well tolerated as a primary treatment for OSSN. Additionally, AS-OCT is a useful noninvasive adjunctive tool in the diagnosis and management of OSSN.