Anti-angiogenic therapy: Prospects for treatment of ocular tumors.

The growth of new blood vessels (angiogenesis) within tumors is essential for tumor growth, maintenance, and metastasis. Angiogenesis research has identified a host of pro- and anti-angiogenic factors that regulate an "angiogenic switch," which when turned on, allows tumors to assume a more aggressive form. Angiogensis inhibitors that target this switch are in clinical trials for a wide array of tumor types. Although angiogenesis inhibitors are already widely used to treat ocular disease, only limited case reports are currently available for the use of angiogenesis inhibitors to treat ocular tumors. Evidence for angiogenesis in the growth and spread of uveal melanoma, retinoblastoma, and von Hippel Lindau (VHL) disease exists. The very limited trials of angiogenesis inhibitors in the treatment of uveal melanoma and VHL are promising, although more extensive controlled trials will be needed to confirm their efficacy.