Figure 1. FDG-PET and CT scans of a patient with non-small cell lung cancer demonstrating a good partial response to chemotherapy. There is a 61% decrease in FDG uptake 3 weeks after initiation of chemotherapy. Reproduced with kind permission of the American Society of Clinical Oncology from: Weber WA, et al. Positron emission tomography in non-small-cell lung cancer: prediction of response to chemotherapy by quantitative assessment of glucose use. J Clin Oncol 2003;21:2651–7.