The prognostic significance of FDG PET-CT standardized uptake value in patients with non-small cell lung cancer

Objective To determine the prognostic value of standardized uptake value(SUV)of fluorodeoxyglucose(FDG)by positron emission tomography and computed tomography(PET-CT)in nonsmall cell lung cancer(NSCLC).Methods Forty-eight patients(39 male,9 female)with stage ⅢNSCLC were reviewed.All patients had at least two repeated FDG PET-CT scans either before and after therapy and the maximum standardized uptake value(SUVmax)of the primary lung lesion was calculated. Resuits Of the 45 eligible patients,after a median follow-up of 22.5 months(rang,13 to 35 months),24 patients had local and regional recurrenee or metastasis and 21 remain disease-free.The mean SUVmax of patients who had local recurrence or metastasis before and after treatment was 12.30±3.17 and 5.35±2.29,respectively.The mean SUVmax of patients who had no loeal recurrence or metastasis before and after treatment was 8.46±3.00 and 2.82±0.63,respectively.Significant differences(tbefore=4.15,Pbefore＜0.01;Pafter=4.88,Pafter＜0.01)in SUVmax were observed either before and after treatment.However,the percent change of SUVmax between pretreatment and post-treatment were not significiantly different(t=1.99,P＞0.05).Using the SUVbefore of 9.0 yielded 92% sensitivity,62% specificity,73% positive predictive value and 87%negaffve Dredictive value in predicting regional recurrence or metastasis. While using the SUVafter of 4.3 yielded 71% sensitivity,100% specificity,100% positive predictive valne and 72% negative Dredictive value. Conclusions PET-CT may have the potientials to predict response to therapy and the SUVmax is a significant predictor for recurrent or metastasis in patients of NSCLC. Key words: Lung neoplasms; Tomography,Positron emission; Prognosis