Page 79 - Fisica In Medicina n° 1/2017

^Äëíê~Åí=jÉÇáÅá= =Stereotactic Ablative Radiation Therapy for lung oligometastases: predictive parameters of early response by 18FDG-PET/CTR. MAZZOLA1, U. TEBANO1, N. GIAJ-LEVRA1, A. FIORENTINO1, F. SERGIO1, F.RICCHETTI1, G. SICIGNANO1, S. NACCARATO1, R. RUGGIERI1, F. ALONGI11Radiation Oncology Division, Sacro Cuore Don Calabria Cancer Care Center, Negrar-Verona, ItalyIntroductionAim: to investigate the role of 18FDG-PET/CT parameters as predictive of early response after Stereotactic Ablative Radiation Therapy (SABR) for oligometastatic lung lesions.Materials and methodsSABR for lung oligometastases was performed when the following criteria were satisfied: a) controlled primary tumor, b) absence of progressive disease longer than 6 months, c) number of metastatic lesions ≤ 5. The prescribed total dose varied according to the risk-adapted dose prescription with a range of doses between 48-70 Gy given in 3-10 fractions. Inclusion criteria of the current retrospective study were: a) lung oligometastases underwent to SABR, b) for each patient presence of 18-FDG-PET/CT pre- and post-SABR for at least two subsequent evaluations, c) Karnofsky performance status > 80, d) life-expectancy > 6 months.The following metabolic parameters were defined semi-quantitatively for each lung lesion: 1) SUV- max, 2) SUV-mean, 3) Metabolic Tumor Volume (MTV), 4) Total Lesional Glycolysis (TLG).ResultsFrom January 2012 to November 2015 fifty patients for a total of seventy lung metastatic lesions met the inclusion criteria of the present analysis. Pre-SABR, median SUV-max was 6.5 (range: 4 - 17), median SUV-mean was 3.7 (2.5 - 6.5), median MTV was 2.3 cc (0.2 - 31 cc). For patients with in-field disease progression median TLG was 17.4 (2 - 52.8), for the remaining patients the median value was 170.6 (0.5 - 171). For pre-SABR SUV-max ≥ 5 a progression/stable metastasis was noted70