Managing the "known unknowns": theranostic cancer nanomedicine and informed consent.

The potential clinical applications and the economic benefits of theranostics represent a tremendous incentive to push research and development forward. However, we should also carefully examine the possible downsides. In this chapter, we address the issue of how theranostics might challenge our current concept of informed consent, especially the disclosure of information concerning diagnosis and treatment options to human subjects. We argue that our lack of data concerning long-term effects and risks of nanoparticles on human health and the environment could undermine the process when it comes to weighing the risks against the benefits. Our lack of an agreed upon framework for risk management in nanomedicine may require us to adopt an "upstream" approach that emphasizes communication and transparency among all relevant stakeholders to help them make informed choices that enable safety or progress.