Fig. 4

Example fused axial PET/CT images for patients with metastatic NSCLC whose response classification was changed using our new criteria (compared to the EORTC criteria). Case 1 had a single liver lesion that showed a 20 % decrease in SUVmax after 2 weeks of treatment and was classified as SMD by EORTC criteria. This patient was reclassified by our scheme as PMR because the baseline lesion SUVmax was 19, resulting in a narrow confidence interval for spurious changes. Case 2 has a single upper lung lesion demonstrating a 33 % decrease in SUVmax that was classified as PMR using the EORTC criteria. This patient was reclassified to SMD using our criteria, as a result of a low screening SUV value of 3.3. (These cases are represented in Fig. 3b as patients #4 and #22)