Vascular co-option in lung cancer metastatic to the eye after treatment with bevacizumab

BACKGROUND: Chemotherapy with bevacizumab alters the angiogenic environment, and therefore, the growth and spread of metastases. We present a patient with metastatic lung adenocarcinoma to the eye with findings suggestive of retinal vascular co-option. METHODS: Case report. RESULTS: A 57-year-old male, receiving systemic bevacizumab for metastatic lung adenocarcinoma, presented with vitreous opacities and clumped deposits adherent to the retinal vessels. No choroidal metastases were present. Diagnostic vitrectomy yielded cellular evidence of adenocarcinoma, with thyroid transcription factor-1 staining confirming a lung primary. CONCLUSION: The perivascular growth of small foci of metastatic vitreous cells suggests vascular co-option from the native retinal circulation. Similar modification of metastatic disease by bevacizumab has been observed in animal models and selected human cases.