In vivo PET Imaging of EGFR Expression: An Overview of Radiolabeled EGFR TKIs

With the development of epidermal growth factor receptor (EGFR)-based tyrosine kinase inhibitors (TKIs) and their applications in the clinic, non-small-cell lung cancer (NSCLC) treatment has entered a new era, and a great number of patients have benefited. However, there still exist other subgroups of patients who may not benefit from EGFR TKIs, although EGFR mutation is the main driving mutation that leads to NSCLC. To identify potential NSCLC responders for TKI therapy and to detect EGFR status in vivo, noninvasive technology, such as TKI PET imaging, has been developed in recent years, and a great number of tyrosine kinase-targeted PET tracers have been reported. The visualization and quantification of EGFR expression in vivo by PET would provide the most important information for personalizing NSCLC therapy and prediction of response in clinical. This article reviews the progress of small molecular tyrosine kinase-targeted PET tracers and their applications in preclinical experiments and clinical studies. The current limitations and future development of these tracers are also briefly discussed.