Positron emission tomography-computed tomography on predicting the efficacy of targeted therapy for lung adenocarcinoma.

Background In this study, positron emission tomography-computed tomography ( PET-CT) was used to monitor the maximal standard uptake value ( SUVmax) in advanced lung adenocarcinoma patients with epithermal growth factor receptor ( EGFR) mutation to prove its role in predicting the prognosis of targeted therapy. Methods A total of 46 patients with advanced lung adenocarcinoma ( IIIb- IV stage) were enrolled in the current study. They were positive for EGFR mutation. All patients received gefitinib (250 mg per day, administered orally). PET- CT was conducted prior to (at baseline) and six months after gefitinib administration for the lesion size and SUVmax. The recommendations of the European Organization for Research and Treatment of Cancer criteria were chosen for PET assessment. Metabolic response ( SUV decline < −25%) was compared with morphologic response evaluated by CT scan and overall survival. Result Compared to patients with △ SUV% ≥ 25% (progressive metabolic disease), the survival time was significantly prolonged in △ SUV% < −25% (including complete metabolic response and progressive metabolic disease) (10.6/18.4, P = 0.000), but was not in −25% ≤ △ SUV% < 25% (stable metabolic disease) (10.6/10.7, P = 0.088). Patients who achieved △ SUV% < −25% after treatment were associated with a longer median survival, higher control rate, and better prognosis. There was a strong correlation between SUV changes (△ SUV%) and CT size change (△lesion size%) (R2 = 0.891, P = 0.000). Conclusion Changes in the SUV could be used to predict the prognosis of targeted therapy in advanced lung adenocarcinoma. [ABSTRACT FROM AUTHOR]