TY - JOUR T1 - <sup>18</sup>F-FLT PET/CT as a Prognostic Imaging Biomarker of Disease-Specific Survival in Patients with Primary Soft-Tissue Sarcoma JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 708 LP - 712 DO - 10.2967/jnumed.121.262502 VL - 63 IS - 5 AU - Joseph G. Crompton AU - Wesley R. Armstrong AU - Mark A. Eckardt AU - Ameen Seyedroudbari AU - William D. Tap AU - Sarah M. Dry AU - Evan R. Abt AU - Jeremie Calais AU - Ken Herrmann AU - Johannes Czernin AU - Fritz C. Eilber AU - Matthias R. Benz Y1 - 2022/05/01 UR - http://jnm.snmjournals.org/content/63/5/708.abstract N2 - The purpose of this study was to evaluate 18F-FLT PET/CT as an early prognostic imaging biomarker of long-term overall survival and disease-specific survival (DSS) in soft-tissue sarcoma (STS) patients treated with neoadjuvant therapy (NAT) and surgical resection. Methods: This was a 10-y follow-up of a previous single-center, single-arm prospective clinical trial. Patients underwent 18F-FLT PET/CT before treatment (PET1) and after NAT (PET2). Posttreatment pathology specimens were assessed for tumor necrosis or fibrosis and for Ki-67 and thymidine kinase 1 expression. Maximally selected cutoffs for PET and histopathologic factors were applied. Survival was calculated from the date of subject consent to the date of death or last follow-up. Results: The study population consisted of 26 patients who underwent PET1; 16 of the 26 with primary STS underwent PET2. Thirteen deaths occurred during a median follow-up of 104 mo. In the overall cohort, overall survival was longer in patients with a low than a high PET1 tumor SUVmax (dichotomized by an SUVmax of ≥8.5 vs. &lt;8.5: not yet reached vs. 49.7 mo; P = 0.0064). DSS showed a trend toward significance (P = 0.096). In a subanalysis of primary STS, DSS was significantly longer in patients with a low PET1 tumor SUVmax (dichotomized by an SUVmax of ≥8 vs. &lt;8; P = 0.034). There were no significant 18F-FLT PET response thresholds corresponding to DSS or overall survival after NAT at PET2. Conclusion: 18F-FLT PET may serve as a prognostic baseline imaging biomarker for DSS in patients with primary STS. ER -