Correlation Between 18F-Fluorodeoxyglucose Uptake and Epidermal Growth Factor Receptor Mutations in Advanced Lung Cancer

Abstract

Purpose Mutations in the epidermal growth factor receptor (EGFR) gene have been identified as potential targets for the treatment and prognostic factors for non-small cell lung cancer (NSCLC). We assessed the correlation between fluorodeoxyglucose (FDG) uptake and EGFR mutations, as well as their prognostic implications.

Methods A total of 163 patients with pathologically confirmed NSCLC were enrolled (99 males and 64 females; median age, 60 years). All patients underwent FDG positron emission tomography before treatment, and genetic studies of EGFR mutations were performed. The maximum standardized uptake value (SUVmax) of the primary lung cancer was measured and normalized with regard to liver uptake. The SUVmax between the wild-type and EGFR mutant groups was compared. Survival was evaluated according to SUVmax and EGFR mutation status.

Results EGFR mutations were found in 57 patients (60.8 %). The SUVmax tended to be higher in wild-type than mutant tumors, but was not significantly different (11.1 ± 5.7 vs. 9.8 ± 4.4, P = 0.103). The SUVmax was significantly lower in patients with an exon 19 mutation than in those with either an exon 21 mutation or wild type (P = 0.003 and 0.009, respectively). The EGFR mutation showed prolonged overall survival (OS) compared to wild-type tumors (P = 0.004). There was no significant difference in survival according to SUVmax. Both OS and progression-free survival of patients with a mutation in exon 19 were significant longer than in patients with wild-type tumors.

Conclusion In patients with NSCLC, a mutation in exon 19 was associated with a lower SUVmax and is a reliable predictor for good survival.