A Rare Presentation of Metastatic Renal Cell Carcinoma Masquerading as Vitritis: A Case Report and Review of Literature

Abstract

We report a case of a 74-year-old gentleman who presented with floaters and decreased vision in the right eye after cataract surgery. His past medical history was significant for metastatic renal cell carcinoma (mRCC) to bone, lung and abdomen which was presumed stable for the last two years while on the tyrosine kinase inhibitor (TKI), pazopanib. Clinical examination revealed significant vitritis with a distinctive clumping of cells on the pre-retinal surface and posterior hyaloid face. Magnetic resonance imaging of the brain revealed new lesions suspicious for metastases. A diagnostic vitrectomy was performed to determine the nature of the vitritis and clear the visual axis. Cytopathologic evaluation of the vitreous demonstrated clusters of malignant cells that were positive for AE1/AE3 and PAX-8, and negative for the CD20, CD3, RCC, SOX-10 and S-100 immunohistochemical markers. The overall findings favored a metastatic RCC to the vitreous. Choroidal and retinal metastases from mRCC have been previously reported; however, vitreous involvement by mRCC with no evidence of retinal or choroidal mass has not been described. New treatments of mRCC include TKIs which target vascular endothelial growth factor receptors (VEGFRs). Herein, we analyze the factors that could have precipitated this unusual metastasis to the vitreous.

“Retinal Vasculitis” With Bilateral Retinal Detachments

“…The most frequently involved site was the orbit (36.8%), followed by the choroid (29.4%), and RCC metastases were predominantly unilateral, with only 4 bilateral reported cases . There is a single report in the literature of unilateral RCC ocular metastasis presenting as vitritis with no retinal or choroidal mass, although retinal metastasis presenting as retinal vascular sheathing and retinitis has been reported previously in other solid organ tumors …”

“…The patient initially presented with “retinal vasculitis” and panuveitis after RD repair; however, it is possible that the sclerotic vessels were a result of metastatic cellular intravascular deposits causing occlusive disease and severe nonperfusion. Metastatic RCC is a highly vascular tumor type—due to both the overproduction of vascular endothelial growth factor and other proangiogenic cytokines and alterations in the von Hippel–Lindau tumor suppressor gene . Renal cell carcinoma is metastatic in 30% of patients, and it portends a poor prognosis, with a median survival of approximately 13 months and a 5-year survival of less than 10% …”