Metastatic Hepatocellular Carcinoma to the Orbit Presenting as a Subperiosteal Abscess

A 76-year-old male with a history of Crohn disease on 6-mercaptopurine, multiple myeloma, and hepatocellular carcinoma presented with 2 days of left-sided painless proptosis and eyelid swelling. Ophthalmological examination showed visual acuity 20/20 OD and 20/200 OS, intraocular pressure 13 in the OD and 20 in the OS, and no afferent pupillary defect in either eye. He had limited adduction and supraduction of the OS. External examination showed proptosis of the left globe, ptosis, and periorbital edema and erythema. CT with contrast of the orbits showed patchy sinusitis and a low attenuated homogenous fluid collection in the left superonasal subperiosteal space (Panel A,B). Differential diagnosis included subperiosteal abscess, subperiosteal hematoma, and orbital metastasis. Otolaryngology offered to perform concurrent endoscopic sinus surgery with anterior orbitotomy given patient's chronic sinusitis history and to decrease potential anesthesia risk for the patient. Pathology specimen of the tan-pink biopsied lesion revealed sheets of discohesive polygonal tumor cells with abundant eosinophilic cytoplasm and prominent nucleoli (Panel C: 4× magnification, Panel D: 40× magnification). Immunohistochemical staining confirmed hepatocellular carcinoma (40× magnification) with strong, diffuse positive staining for cytokeratin 8/18 in viable tumor cells (Panel E) and arginase-1 in the nucleus and cytoplasm (Panel F). Hepatocellular carcinoma is a rare cause of metastatic orbital malignancy. This case demonstrates the need for a low threshold for diagnostic biopsy for a potential underlying metastatic lesion in patients with a history of cancer for new onset proptosis.