Topical Mitomycin C For Pre-Invasive Ocular Surface Squamous Neoplasia In A Patient With Xeroderma Pigmentosum: A Case Report

To highlight the successful non-surgical management of a pre-invasive ocular surface squamous neoplasia (OSSN) lesion in a xeroderma pigmentosum (XP) patient, using pulse topical mitomycin C (MMC) therapy guided by anterior segment optical coherence tomography (AS-OCT).

A private ophthalmology clinic with a specialized cornea and refractive surgery unit.

A 38-year-old female with XP presented with a progressively enlarging, vascularized lesion on the nasal conjunctiva extending from 3 to 6 clock hours onto the cornea. Initially treated as pterygium without improvement, the lesion raised suspicion for neoplastic changes. High-resolution AS-OCT imaging revealed characteristic epithelial thickening and hyperreflective changes, consistent with pre-invasive OSSN. The patient was treated with topical MMC 0.02% applied in a pulse regimen (two weeks on, one week off) and monitored biweekly by AS-OCT. Within five months, the lesion completely regressed, with visual acuity improving from counting fingers to 0.1 (20/200). No adverse effects such as ocular surface toxicity or limbal stem cell deficiency were observed. Long-term follow-up confirmed sustained resolution without recurrence.

AS-OCT-guided topical MMC therapy provided a safe, effective, and non-surgical approach for controlling pre-invasive OSSN in an XP patient. This case underscores the importance of regular ophthalmic surveillance in XP patients and highlights the need to re-evaluate lesions that do not respond to standard therapies, as they may represent early neoplastic changes rather than benign conditions.