Design and conduct of theranostic trials in neuro-oncology: Challenges and opportunities.

Theranostics is a new treatment modality integrating molecular imaging with targeted radionuclide therapy. Theranostic agents have received regulatory approval for some systemic cancers and have therapeutic potential in neuro-oncology. As clinical trials are developed to evaluate the efficacy of theranostic agents in brain tumors, specific considerations will have to be considered, taking into account lessons learned from previous studies examining other treatment modalities in neuro-oncology. These include the need for molecular imaging or surgical window-of-opportunity studies to confirm adequate passage across the blood-brain barrier, optimizing eligibility criteria and selection of the most appropriate response criteria and endpoints to address issues such as pseudoprogression. This review will discuss some of the issues that should be considered when designing clinical trials for theranostic agents.