Large extraocular extension of a choroidal melanoma with orbital inflammation

PURPOSE: To describe an atypical case of a choroidal melanoma presenting with eyelid edema, chemosis, pain and diplopia and demonstrating significant extraocular extension on ultrasonography and neuroimaging. OBSERVATIONS: A 69-year-old woman presented with a headache, eyelid edema, chemosis and pain in the right eye. Upon subsequent onset of diplopia, MRI of the orbits was performed and demonstrated a predominantly extraocular, intraconal mass with a small intraocular component. She was started on corticosteroids and referred to the ocular oncology service for evaluation. On fundus examination, she was noted to have a pigmented choroidal lesion consistent with melanoma, and ultrasound showed a large area of extraocular extension. Enucleation, enucleation with subsequent radiation and exenteration were discussed, and the patient requested an opinion from radiation oncology. A repeat MRI obtained by radiation oncology demonstrated a decrease in the extraocular component after corticosteroid treatment. The improvement was interpreted as suggestive of lymphoma by the radiation oncologist who recommended external beam radiation (EBRT). Fine needle aspiration biopsy was insufficient for cytopathologic diagnosis, and the patient elected to proceed with EBRT in the absence of a definitive diagnosis. Next generation sequencing revealed GNA11 and SF3B1 mutations, which supported the diagnosis of uveal melanoma and led to enucleation. CONCLUSION AND IMPORTANCE: Choroidal melanoma may present with pain and orbital inflammation secondary to tumor necrosis, which may delay diagnosis and decrease the diagnostic yield of fine-needle aspiration biopsy. Next generation sequencing may aid the diagnosis of choroidal melanoma when there is clinical uncertainty and cytopathology is unavailable.