Preclinical PET, SPECT, CT, MRI and optical imaging in cancer research: An overview

Cancer research is primarily dependent on rodent models. There has been a huge advancement in anticancer drug discovery in the last two decades, which is mainly due to improved animal models and introduction of non-invasive imaging technologies. Non-invasive imaging technology plays an important role in cancer and other biomedical research areas including neurology, cardiology, nanotechnology and stem cell biology. The intricate pathways in cancer initiation, progression and metastasis can be visualized and the processes can be analyzed quantitatively using these techniques. Robust preclinical data is the backbone of anticancer drug discovery, which can be obtained precisely using imaging technology. This review is focused on the dedicated preclinical imaging modalities such as Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), X-ray Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Optical imaging and Cerenkov imaging. This paper discusses their present roles in basic and translational research towards evaluation of suitability of target molecules for further clinical trials.The unique features of the imaging modalities enable them to provide information necessary for understanding structural, functional and molecular processes involved in various stages of cancer development thus bridging the gap between bench and bedside.