Metabolic response evaluated by 18F-FDG PET/CT as a potential tool in identifying subgroup of patients with advanced non-small cell lung cancer for immediate maintenance treatment after first-line chemotherapy.

Abstract

e18148 Background: Platinum-based doublet regimens have been a mainstay of first-line treatment with advanced non–small cell lung cancerand ans the present guidelines recommend four to six cycles and waiting until disease progression. However subsequent disease progression is often rapid so sequential and maintenance therapy was performed in many studies. But almost studies didn’t show the significant survival benefit. Thus, we supposed that FDG PET may be a useful to determine what subgroup have better prognosis Methods: We founded out fifty-two patients who diagnosed to underwent baseline and follow-up FDG PET after 4 cycles of first-line platinum based chemotherapy. We obstained patient's characteristics and response rate (RR), progression-free survival (PFS), and overall survival (OS) from the medical records. And we checked maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG) from FDG PET. Results: Univariate analysis showed that MTV (hazard ratio = 1.032, P = 0.007) and TLG (hazard ratio = 1.030, P = 0.001) were independent predictive factors associated with decreased PFS and gender (hazard ratio = 5.248, P = 0.026), smoking (hazard ratio = 7.798, P = 0.006), EGFR mutation (hazard ratio = 0.106, P = 0.030) and TLG (hazard ratio = 1.027, P = 0.046) were significant predictors of OS. Histopathology was a marginally significant prognostic factor (P = 0.058). Multivariate analysis showed that TLG (hazard ratio = 1.030, P = 0.001) were independent predictive factors associated with decreased PFS and smoking (hazard ratio = 10.588, P = 0.002) and TLG (hazard ratio = 1.043, P = 0.007) were significant predictors of OS. Conclusions: There is a correlation between TLG and PFS significantly. We suggest that follow-up FDG PET after 4 cycle chemotherpy can help to discriminate patients who have benefit through sequential and maintenance therapy. But it need specific value for clinical use, so more large-scale prospective study is warranted.