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 (TLG_RECIST). 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 TLG_RECIST 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, TLG_RECIST 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.