Total lesion glycolysis determined per RECIST 1.1 criteria predicts survival in EGFR mutation-negative patients with advanced lung adenocarcinoma

Objective: The aim of this retrospective study was to investigate the clinical impact of 18F-FDG PET in patients with advanced lung adenocarcinoma stratified according to the epidermal growth factor receptor (EGFR) mutation status. Patients and Methods: A total of 56 patients with advanced lung adenocarcinoma were included in the study. Thirty-one patients (55%) were EGFR mutation-positive, whereas the remaining 25 (45%) participants tested negative for EGFR mutations. All of the patients underwent 18F-FDG PET/CT for pretreatment planning. The main outcome measure was overall survival (OS) at 24 months. The following 18F-FDG PET/CT-derived variables were tested for their associations with OS: main tumor SUV max, main tumor total lesion glycolysis, and target lesions TLG determined per RECIST (Response Evaluation Criteria In Solid Tumors) 1.1 criteria (TLGRECIST). We also investigated the clinical characteristics in relation to OS and EGFR mutation status. Results: In EGFR mutation-positive patients, neither the clinical characteristics nor 18F-FDG PET/CT-derived parameters were significantly associated with OS. In contrast, univariate analysis identified male sex, a positive history of smoking, and TLGRECIST greater than or equal to 412 g as adverse prognostic factors for OS in EGFR mutation-negative patients. After adjustment for potential confounders in multivariate analysis, TLGRECIST was the sole independent predictor of OS in this subgroup. Conclusions: TLG determined per RECIST 1.1 criteria is an independent predictor of OS in EGFR mutation-negative patients with advanced lung adenocarcinoma. Further studies are needed to investigate whether this parameter may be a promising tool for stratifying such patients for risk-adapted therapies.