Importance: Individualized cancer treatment, tailored to a particular patient and the tumor's biological features (precision oncology), requires a detailed knowledge of tumor biology. Biological characterization is typically performed on biopsy material, but this approach can present challenges for widespread and/or heterogeneous disease and for performing serial assays to infer changes in response to therapy. Molecular imaging is a complementary approach that provides noninvasive and quantitative measures of the in vivo biology of the full disease burden and is well suited to serial assay.
Observations: Molecular imaging can provide unique information to guide precision oncology that includes measuring the regional expression of therapeutic targets, measuring drug pharmacokinetics, measuring therapy pharmacodynamics, and providing a marker of therapeutic efficacy that is highly indicative of outcome. Thus far, most trials of novel molecular imaging in oncology have been small, single-center trials. Only a few methods have progressed to multicenter trials and even fewer have become part of clinical practice.
Conclusions and relevance: Molecular imaging holds great promise for precision oncology, complementing tissue-based markers to guide more effective, less toxic, and more cost-effective cancer treatments. Beyond logistical and technical challenges, moving new imaging tests from the laboratory to the clinic requires a compelling use case that will benefit patients and/or improve cost-effectiveness, and it requires the collaboration of imagers, oncologists, and industry to reach its true clinical potential.