F-18 FDG PET/CT characterization and predictive efficacy for driver mutation positive and negative pulmonary adenocarcinoma in correlation with clinico-pathologic data

Abstract

Background: Fluorine-18 (isotope)-Fluoro-deoxyglucose positron emission tomography computed tomography (F-18-FDG PET/CT) as a non-invasive method could predict driver mutation status in pulmonary adenocarcinoma. Aim: To assess whether F-18 FDG PET/CT can differentiate between positive and negative driver mutation status of pulmonary adenocarcinoma. Settings and Design: Hundred biopsy proven, untreated pulmonary adenocarcinoma patients tested for EGFR and ALK gene mutations underwent staging F-18 FDG PET/CT scan at our institute. Methods and Material: Metabolic parameters like SUVmax of the primary (pSUVmax), SULpeak, SUVmean, Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of primary lesion, SUVmax of the most avid metastatic regional lymph node (nSUVmax) and extra thoracic metastasis (mSUVmax) and average SUVmax of the primary lesion, regional nodal metastasis and extra thoracic metastasis were calculated. Statistical Analysis Used: The independent sample ‘T’ test and Mann-Whitney U test were used for analysis. Receiver operating characteristic (ROC) curves were used to determine the cut-off value of pSUVmax for predicting ALK mutation status. Results: Fourty one patients showed EGFR mutations, 14 showed ALK rearrangements and 45 were wild-type. Patients with ALK rearrangements showed a lower pSUVmax, SULpeak, SUVmean and TLG compared to wild type patients. ROC curve analysis showed a pSUVmax cutoff of < 11.0 yielding an area under the curve (AUC) of 0.709. Patients with EGFR mutations showed a lower mSUVmax, MTV, and TLG compared to wild type. Conclusions: FDG- PET/CT can be a useful non- invasive tool if tumor tissue is not available, although genetic testing continues to be the gold standard.

Keywords

• fdg/pet ct
• driver mutation
• pulmonary adenocarcinoma
• metabolic parameters
• egfr
• alk