18F-FDG uptake and EGFR mutations in patients with non-small cell lung cancer: a single-institution retrospective...

This retrospective study was performed to evaluate a possible association between the presence of epidermal growth factor receptor (EGFR) mutations and the standardized uptake value (SUV) of (18)F-fluoro-2-deoxy-glucose ((18)F-FDG) uptake in patients with non-small cell lung cancer (NSCLC). We included 100 patients who were tested for EGFR mutations by direct sequencing of resected tissues and who underwent preoperative positron emission tomography/computed tomography at the time of diagnosis. The maximum SUV by the primary tumor was chosen for further analysis. EGFR mutations in exons 19 and 21 were detected in 21 NSCLC patients (21%). EGFR mutations were more frequent in never-smokers than ever-smokers (35% versus 11%; P=0.003), in adenocarcinomas than non-adenocarcinomas (34% versus 6%; P=0.001), and in females than males (41% versus 12%; P=0.001). The SUV ranged from 1.3 to 33.0 (median 10.6). Area under receiver operating characteristic curve for SUVs in respect to the presence of EGFR mutations was 0.74 (95% CI: 0.62-0.85). When a cut off value was used, patients with low SUVs were more likely to have EGFR mutations than those with high SUVs (40% versus 11%; P=0.001). On multivariate analysis, a low SUV remained a significant predictors for EGFR mutations (P=0.025). (18)F-FDG uptake was associated with the presence of EGFR mutation. These results extrapolate that (18)F-FDG uptake might be helpful to discriminate patients who harbor EGFR mutations, especially when a genetic test is not feasible.