TY - JOUR T1 - <sup>18</sup>F-FDG PET/CT imaging biomarkers for early and late evaluation of response to first-line chemotherapy in patients with pancreatic ductal adenocarcinoma JF - Journal of Nuclear Medicine JO - J Nucl Med DO - 10.2967/jnumed.121.261952 SP - jnumed.121.261952 AU - Matthias R. Benz AU - Wesley R. Armstrong AU - Francesco Ceci AU - Giulia Polverari AU - Timothy R. Donahue AU - Zev A. Wainberg AU - Andrew Quon AU - Martin Auerbach AU - Mark D. Girgis AU - Ken Herrmann AU - Johannes Czernin AU - Jeremie Calais Y1 - 2021/07/01 UR - http://jnm.snmjournals.org/content/early/2021/07/16/jnumed.121.261952.abstract N2 - Purpose: The purpose of this study was to evaluate 18F-FDG-PET/CT as an early and late interim imaging biomarker in patients with pancreatic ductal adenocarcinoma (PDAC) who undergo first-line systemic therapy. Methods: This was a prospective, single-center, single-arm, open-label study (IRB12-000770). Patient receiving first line chemotherapy were planned to undergo a baseline 18F-FDG-PET/CT (PET1), early interim 18F-FDG PET/CT (PET2) and late interim 18F-FDG-PET/CT (PET3). ROC selected and established (mPERCIST / RECIST1.1) cut-offs for metabolic and radiographic tumor response assessment were applied. Patients were followed to collect data on further treatments and overall survival (OS). Results: The study population consisted of 28 patients who underwent PET1. Twenty-three of these (82%) underwent PET2 and 21 (75%) PET3, respectively. Twenty-three deaths occurred during a median follow up period of 14 months (maximum follow up, 58.3 months). The median OS was 36.2 months (95%CI, 28-NYR) in early metabolic responders (6/23 (26%), P = 0.016) and 25.4 months (95%CI, 19.6-NYR) in early radiographic responders (7/23 (30%), P = 0.16). The median overall survival was 27.4 months (95%CI, 21.4-NYR) in late metabolic responders (10/21 (48%), P = 0.058) and 58.2 months (95%CI, 21.4-NYR) in late radiographic responders (7/21 (33%), P = 0.008). Conclusion: 18F-FDG PET may serve as early interim imaging biomarker (~ at 4 weeks) for evaluation of response to first-line chemotherapy in patients with PDAC. Radiographic changes might be sufficient for response evaluation after the completion of first line chemotherapy. ER -