TY - JOUR T1 - <sup>11</sup>C-Methionine <em>vs</em>. <sup>18</sup>F-FDG PET in Soft Tissue Sarcoma Patients Treated with Neoadjuvant Therapy: Preliminary Results JF - In Vivo JO - In Vivo SP - 105 LP - 110 VL - 23 IS - 1 AU - GIULIA GHIGI AU - RENATO MICERA AU - ANNA MARGHERITA MAFFIONE AU - PAOLO CASTELLUCCI AU - SILVIA CAMMELLI AU - ILARIO AMMENDOLIA AU - CRISTINA NANNI AU - ENZA BARBIERI AU - GAIA GRASSETTO AU - STEFANO FANTI AU - DOMENICO RUBELLO Y1 - 2009/01/01 UR - http://iv.iiarjournals.org/content/23/1/105.abstract N2 - Objective: In patients with soft tissue sarcoma (STS) the histological response (tumour grade regression: TGR) to neoadjuvant chemoradiotherapy (CRT) may influence the outcome. The main aim of the study was to evaluate the predictive value of 11C-methionine (MET) and 18F-FDG PET/CT in patients with STS treated with neoadjuvant CRT, correlating TGR with SUVmax (standardized uptake value) percentage variation before and after CRT. Patients and Methods: Nine patients with STS already scheduled for a neoadjuvant CRT and surgery were enrolled. They underwent MET and FDG PET/CT in a one-day procedure before and after the CRT. Pre-therapy SUVmax and the percentage variation of SUVmax for MET and FDG were correlated with TGR according to the Huvos grade. Grades I-II were considered as partial responders (PR) and grades III-IV as complete responders (CR). Results: FDG pre-treatment mean SUVmax in PR patients was 7.1, while in CR patients it was 13.2. Pre-treatment mean MET SUVmax in PR patients was 7.5, while in CR patients it was 4.9. The mean percentage variation in FDG SUVmax, was -21.2% in PR patients and -74.5% in CR patients while that for MET SUVmax was 48% in PR patients and -53.9% in CR patients. Conclusion: According to this preliminary study, the percentage variation in FDG before and after CRT seems to discriminate between PR and CR better than MET. ER -