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 treatment of 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 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 those with either an exon 21 mutation or wild-type (P =20.003 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 toSUVMAX. Both OS and progression-free survival of patients with a mutation in exon 19 were significantly longer than in patients with wild-type tumors. Conclusion: In patients with NSCLC, mutation in exon 19 associated with a lower SUVMAX is a reliable predictor for good survival, and is a potential target of EGFR therapy.