Case Report: Atypical ocular surface squamous cell carcinoma.

Ocular surface squamous neoplasia (OSSN) is the most common ocular surface neoplasm. Ocular surface squamous cell carcinoma (OS-SCC) represents the invasive malignant component within the spectrum of OSSN. The patient in this case report presented with manifestations resembling herpes simplex keratitis at the initial visit, without the typical clinical features of OS-SCC. The diagnosis was revised after close follow-up, and the patient achieved improvement with anti-metabolite therapy. At the time of recurrence, the clinical manifestations were similar to scleral abscess, still without the typical features of OS-SCC. A definitive diagnosis was finally confirmed by surgery following close follow-up. This patient lacked typical clinical manifestations of OS-SCC in both episodes of onset. The diagnosis was revised based on close follow-up and a pathological biopsy, and the treatment regimen was adjusted in a timely manner, resulting in a favorable final prognosis.