Elevated Metabolic Activity on 18F-FDG PET/CT Is Associated with the Expression of EZH2 in Non-small Cell Lung Cancer

Abstract

Background/aim: Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that is deeply involved in the pathogenesis of lung cancer. We evaluated the metabolic characteristics of non-small cell lung cancer (NSCLC) in patients with and without expression of EZH2 using ¹⁸F-fluorodeoxyglucose positron-emission tomography/ computed tomography (¹⁸F-FDG PET/CT).

Materials and methods: The EZH2 protein expression of 268 patients with resected NSCLC, whose preoperative ¹⁸F-FDG PET/CT information was available, was evaluated by immunohistochemistry with clone 6A10 antibody; cases with Allred score ≥3 were considered positive.

Results: Maximized standard uptake values in cases of EZH2-positive NSCLC and adenocarcinoma were significantly higher in comparison to EZH2-negative cases (p<0.001, and p<0.001, respectively). The expression of EZH2 in NSCLC and adenocarcinoma was associated with significantly poorer survival.

Conclusion: In patients with NSCLC and adenocarcinoma, EZH2 positivity was associated with a high uptake of FDG, suggesting that EZH2 might define metabolically malignant lung cancer.

Keywords: EZH2; PET/computed tomographic; SUVmax; lung cancer.