Orbital metastasis revealing occult metastatic prostate adenocarcinoma in a South African man: A rare initial ophthalmic presentation

Orbital metastasis is a rare initial presentation of undiagnosed prostate cancer. We report a 65-year-old South African man presenting with a one-year history of progressive, painless right upper eyelid swelling, proptosis, tearing, and vision loss. Imaging revealed a right lateral orbital mass causing bone erosion. An incisional biopsy confirmed metastatic adenocarcinoma with strong prostate-specific antigen positivity. Further evaluation showed an irregular prostate, a serum PSA of 1620 ng/mL, urinary retention, nodal involvement, and extensive bone metastases. A prostate biopsy confirmed high-grade disease (Gleason 9). This case underscores considering a prostatic primary in older men with suspicious orbital masses.