Orbital metastasis of renal cell carcinoma masquerading as Amaurosis fugax.

Renal cell carcinoma (RCC) is the most common malignancy involving the kidney. Only rarely does it metastasize to the eye and orbit, sometimes mimicking other lesions. A 70-year-old woman was referred from neurology because of a right orbital lesion, six months after the start of a neurological investigation because of amaurosis fugax. Six months earlier she had complained of transient visual disturbances in her right eye. After excluding cardiovascular abnormalities and coagulopathies as the source of her complaints, she was diagnosed as having a right senile ptosis. A computed tomography scan, done to complete the workout, detected a right orbital mass. The patient was referred to the oculoplastic unit. A biopsy and then a lateral orbitotomy were performed. Histopathological examination proved it to be a metastatic renal cell carcinoma, seven years after the primary tumor had been diagnosed and treated by nephrectomy. The characteristics of metastatic renal cell carcinoma are discussed, in view of the rarity of metastasis to the eye and, in particular, to the orbit, and its tendency to masquerade as other lesions or symptoms. In this case it presented as amaurosis fugax before other signs appeared.