Objective To evaluate the value of 18 F-fluorodeoxyglucose ( 18 F-FDG) metabolism imaging in evaluating the response of patients with non-small cell lung cancer ( NSCLC) in stable diseaseafter chemotherapy. Methods 28 patients with NSCLC in stable disease after chemotherapy admitted between September 2010 to September 2012 were retrospectively investigated. The reduction ratio of targetto-nontarget ratio ( T/N) before and after chemotherapy was calculated. The patients were followed up 3 to 12 months to measure progression-free survival ( PFS) . The correlation between the reduction ratio of T/N and PFS was analyzed. The patients were divided into a reduction group and a non-reduction group according to the difference of the reduction ratio of T/N and was compared the difference of the PFS.Results The reduction ratio of T/N had positive correlation with PFS( Pearson r = 0. 668, P lt; 0. 01) . The PFS of the reduction group was longer than that in the non-reduction group ( 8. 0 ±2. 5 months vs. 5. 3 ±1. 2 months,P lt;0. 05) . Conclusions The reduction ratio of T/N is positively correlated with PFS in NSCLC patients in stable disease after chemotherapy. It is possible to evaluate the efficacy of the treatment according to the reduction ratio of T/N.
