Intraocular schwannoma with extrascleral extension

To report a rare case of intraocular schwannoma with extrascleral extension in a patient with juvenile idiopathic arthritis and to review the literature for this topic.

Case report.

A 19-year-old male with a history of juvenile idiopathic arthritis was referred for diagnosis and management of an episcleral mass, initially thought to be focal nodular scleritis. The ocular surface of the right eye revealed an elevated amelanotic episcleral nodule inferonasally, with thin strands of overlying sclera, feeding episcleral vessels, and measuring 11 mm × 11 mm in diameter and 5 mm in thickness. Ophthalmoscopic examination revealed a minimally pigmented ciliochoroidal tumor measuring 13 mm in diameter and 11.4 mm in total thickness and without associated subretinal fluid, orange pigment, or drusen. Ultrasound biomicroscopy and anterior-segment optical coherence tomography confirmed a solid mass with scleral disruption and extraocular extension. Shave biopsy revealed palisading spindle cells and interspersed eosinophilic fibrillary cytoplasmic processes, forming Verocay bodies. The specimen stained positive for S-100 and negative for Melan-A, consistent with benign schwannoma. Observation was recommended.

Intraocular schwannoma is a rare, benign uveal tumor that can demonstrate extrascleral extension, mimicking inflammatory and malignant neoplastic processes. Clinical diagnosis is challenging, and tissue biopsy is required for definite diagnosis.