Preclinical imaging in oncology: advances and perspectives

Preclinical imaging with radiolabeled probes became an integral part of the complex translational process that moves a newly developed compound from laboratory to clinical application. Imaging studies in animal tumor models may be undertaken to test a newly synthesized tracer, a newly developed drug or to interrogate, in the living organism, specific molecular and biological processes underlying tumor growth and progression. The aim of the present review is to outline the current knowledge and future perspectives of preclinical imaging in oncology by providing examples from recent literature. Among the biological processes and molecular targets that can be visualized with radiolabeled probes in animal tumor models, we focused on proliferation, expression of targets suitable for therapy, glycolytic phenotype, metastatic dissemination, tumor angiogenesis and survival. The major contribution of preclinical imaging emerging from these studies is the development and validation of imaging biomarkers that can be translated into the clinical context for patient selection and evaluation of tumor response to molecularly targeted agents.