Role of bevacizumab in the management of the patient with malignant pleural effusion: more questions than answers.

INTRODUCTION: Malignant pleural effusion (MPE) is a feature of metastatic cancer associated with significant morbidity and cost. The typical management of MPE is systemic chemotherapy and mechanical intervention. Vascular endothelial growth factor (VEGF), an inducer of vascular permeability, has been shown to mediate fluid formation. Therefore, bevacizumab, an inhibitor of VEGF, offers theoretical promise for abolishing fluid formation in MPE. Areas covered: This review begins with a summary of VEGF physiology and evidence of its role in MPE pathogenesis. This is followed by an overview of bevacizumab and major trials that put it on the map of non-small cell lung cancer (NSCLC). The majority of the article is devoted to a review of the current evidence base for the use of bevacizumab for MPE control in metastatic pleural malignancy. The review concludes with considerations of patient selection and toxicity. Expert commentary: Evidence in support of bevacizumab administration for MPE management remains flawed. Small studies suggest efficacy of both intravenous and intrapleural routes, but their design raises bias concerns. Bevacizumab appears to be safe in properly selected cases. The future of MPE management may de-emphasize VEGF inhibition in favor of precise molecular therapeutics that could address the root cause of tumorigenesis.