FDG-PET/CT: does the semiquantitative parameter SUVmax have significance as an outcome predictor in patients with newly-diagnosed stage I-II NSCLC? V. Arena1, S. Novello2, A. Skanjeti1, G. Selvaggi2, A. Douroukas1, A. Billè2, M. Giaj Levra2, F Giunta1, M. Longo2, G. V. Scagliotti2, E. Pelosi1,3. 1) Centro PET IRMET, Torino, Italy 2) Università di Torino, Dipartimento di Scienze Cliniche e Biologiche, ASO S. Luigi, Orbassano, Torino, Italy 3) SCDU Medicina Nucleare 2, ASO S. Giovanni Battista, Torino, Italy PURPOSE Malignant tumors are characterized by an increase of glucose metabolism, a cellular aspect which is detected and can be measured with FDG-PET. The aim of our study was to evaluate the prognostic value of SUVmax and diameter of the primary pulmonary lesion in patient with newly diagnosed stage I-II NSCLC. METHODS 43 patients (mean age: 67,3) with newly-diagnosed NSCLC were included in this study. All patients underwent an FDG-PET/CT scan as part of their initial staging work-up. SUVmax and diameter of the primitive lesion were calculated for all patients; patients were followed-up for at least 9 months. For statistical analysis, we divided the patients in two major groups depending on the presence of disease recurrence. Relationship between SUVmax values and diameter versus disease recurrence in the two groups was seeked using the Student t-test. RESULTS 31 patients were disease free after a mean follow-up period of 16 months, while 12 presented a disease recurrence (disease free survival time, mean 10,6 months). The mean values of the SUVmax in the two groups were: 8,96 (SD: 5,26) and 12,8 (SD: 5,3), respectively (p=0.038, student-t test). Lesion dimension mean values were: 31,27 (SD: 18,65) e 40,5 (SD: 9,4). (p=0,11, ns, Student t-test). CONCLUSIONS In this population of patients with stage I-II NSCLC, we found a statistical significant relationship between SUVmax values and disease recurrence.