TY - JOUR T1 - <sup>18</sup>F-FDG PET/CT Prediction of Treatment Outcomes in Human Papillomavirus–Positive, Locally Advanced Oropharyngeal Cancer Patients Receiving Deintensified Therapy: Results from NRG-HN002 JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 362 LP - 367 DO - 10.2967/jnumed.122.264424 VL - 64 IS - 3 AU - Rathan M. Subramaniam AU - Lyudmila DeMora AU - Min Yao AU - Sue S. Yom AU - Maura Gillison AU - Jimmy J. Caudell AU - John Waldron AU - Ping Xia AU - Christine H. Chung AU - Minh Tam Truong AU - Michelle Echevarria AU - Jason W. Chan AU - Jessica L. Geiger AU - Loren Mell AU - Samantha Seaward AU - Wade L. Thorstad AU - Jonathan Jay Beitler AU - Khalil Sultanem AU - Diagjin Blakaj AU - Quynh-Thu Le Y1 - 2023/03/01 UR - http://jnm.snmjournals.org/content/64/3/362.abstract N2 - The purpose of this study was to determine the negative predictive value (NPV) of a 12- to 14-wk posttreatment PET/CT for 2-y progression-free survival (PFS) and locoregional control (LRC) in patients with p16-positive locoregionally advanced oropharyngeal cancer (LA-OPC). Study was a secondary endpoint in NRG-HN002, a noncomparative phase II trial in p16-positive LA-OPC, stage T1-T2, N1-N2b or T3, N0-N2b, and ≤10 pack-year smoking. Patients were randomized in a 1:1 ratio to reduced-dose intensity-modulated radiotherapy (IMRT) with or without cisplatin. Methods: PET/CT scans were reviewed centrally. Tumor response evaluations for the primary site, right neck, and left neck were performed using a 5-point ordinal scale (Hopkins criteria). Overall scores were then assigned as negative, positive, or indeterminate. Patients with a negative score for all 3 evaluation sites were given an overall score of negative. The hypotheses were NPV for PFS and LRC at 2-y posttreatment ≤ 90% versus &gt;90% (1-sided P value, 0.10). Results: A total of 316 patients were enrolled, of whom 306 were randomized and eligible. Of these, 131 (42.8%) patients consented to a posttherapy PET/CT, and 117 (89.3%) patients were eligible for PET/CT analysis. The median time from the end of treatment to PET/CT scan was 94 d (range, 52–139 d). Estimated 2-y PFS and LRC rates in the analysis subgroup were 91.3% (95% CI, 84.6, 95.8%) and 93.8% (95% CI, 87.6, 97.5%), respectively. Posttreatment scans were negative for residual tumor for 115 patients (98.3%) and positive for 2 patients (1.7%). NPV for 2-y PFS was 92.0% (90% lower confidence bound [LCB] 87.7%; P = 0.30) and for LRC was 94.5% (90% LCB 90.6%; P = 0.07). Conclusion: In the context of deintensification with reduced-dose radiation, the NPV of a 12- to 14-wk posttherapy PET/CT for 2-y LRC is estimated to be &gt;90%, similar to that reported for patients receiving standard chemoradiation. However, there is insufficient evidence to conclude that the NPV is &gt;90% for PFS. ER -