Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) is widely used in the management of lung adenocarcinoma. Pyruvate kinase M2 (PKM2) plays a key role in glycolysis. We therefore investigated whether PKM2 expression affects 18F-FDG uptake in a retrospective analysis of 76 patients who underwent 18F-FDG PET/computed tomography (CT) scans for staging before surgical resection. We found that PKM2 expression was higher in tumors than peritumoral tissue (p < 0.05). Patients with high PKM2 expression had reduced overall (p < 0.05) and disease-free (p < 0.05) survival as compared to those with low PKM2 expression. Comparison of the primary tumor maximum standardized uptake value (SUVmax) between patients with high and low PKM2 expression revealed that the SUVmax was higher in primary tumors with high PKM2 expression than low PKM2 expression (p < 0.05). Multivariate analysis confirmed the association between SUVmax and PKM2 expression (p < 0.05). PKM2 status was predicted with 81.6% accuracy when the SUVmax cutoff value of 6.4. Thus,18F-FDG PET/CT is predictive of the PKM2 status in lung adenocarcinoma patients and could aid in determining therapeutic strategies.
Keywords: 18F-FDG uptake; PKM2; glycolysis; lung adenocarcinomas.