Uveal metastases.

Abstract

Any discussion of ophthalmic oncology must emphasize metastases to the uvea. Consider that an estimated 8– 10% of patients with metastatic malignancy have uveal involvement [1]. Not surprisingly then, metastases are the most common uveal malignancy. The uveal tract’s rich vascularity partly explains this predilection for metastases. Further, the uveal microenvironment seems favorable to metastases since the uvea has the highest percentage of metastatic involvement in relation to blood flow of any tissue in the body [1, 2]. Metastases usually involve the choroid (88% of cases) and rarely involve the iris (9% of cases) or ciliary body (2% of cases) [3]. Multifocality and or bilaterality can help clinically differentiate metastases from primary tumors, especially melanoma. Unfortunately, metastases are often solitary and unilateral [3, 4]. In one large series, metastases were bilateral in only approximately one quarter of patients, and the metastases were solitary in 71% of the involved eyes [3]. Two thirds of patients with uveal metastases have a history of a primary malignancy [3]. Cytologists should exploit this fact when interpreting uveal fine needle aspiration biopsy (FNAB) samples.