In this analysis, we aim to investigate the potential impact of GLUT-1 inhibition by different TKIs on the routine monitoring of tumor response through [18F] FDG-PET imaging and explore the significance of FDG uptake in evaluating responses to targeted therapies with TKIs, exploring its potential as a biomarker for treatment efficacy and patient outcomes using some illustrative examples. The gene discussed is SLC2A1; the disease is neoplasm.