Tumor hypoxia, an integral biomarker to guide radiotherapy, can be imaged with ¹⁸F-fluoromisonidazole (¹⁸F-FMISO) hypoxia PET. One major obstacle to its broader application is the lack of standardized interpretation criteria. We sought to develop and validate practical interpretation criteria and a dedicated training protocol for nuclear medicine physicians to interpret ¹⁸F-FMISO hypoxia PET. Methods: We randomly selected 123 patients with human papillomavirus–positive oropharyngeal cancer enrolled in a phase II trial who underwent 123 ¹⁸F-FDG PET/CT and 134 ¹⁸F-FMISO PET/CT scans. Four independent nuclear medicine physicians with no ¹⁸F-FMISO experience read the scans. Interpretation by a fifth nuclear medicine physician with over 2 decades of ¹⁸F-FMISO experience was the reference standard. Performance was evaluated after initial instruction and subsequent dedicated training. Scans were considered positive for hypoxia by visual assessment if ¹⁸F-FMISO uptake was greater than floor-of-mouth uptake. Additionally, SUV_max was determined to evaluate whether quantitative assessment using tumor-to-background ratios could be helpful to define hypoxia positivity. Results: Visual assessment produced a mean sensitivity and specificity of 77.3% and 80.9%, with fair interreader agreement (κ = 0.34), after initial instruction. After dedicated training, mean sensitivity and specificity improved to 97.6% and 86.9%, with almost perfect agreement (κ = 0.86). Quantitative assessment with an estimated best SUV_max ratio threshold of more than 1.2 to define hypoxia positivity produced a mean sensitivity and specificity of 56.8% and 95.9%, respectively, with substantial interreader agreement (κ = 0.66), after initial instruction. After dedicated training, mean sensitivity improved to 89.6% whereas mean specificity remained high at 95.3%, with near-perfect interreader agreement (κ = 0.86). Conclusion: Nuclear medicine physicians without ¹⁸F-FMISO hypoxia PET reading experience demonstrate much improved interreader agreement with dedicated training using specific interpretation criteria.

肿瘤缺氧是指导放疗的整体生物标志物，可以用 ¹⁸F-氟米索尼达唑 （¹⁸F-FMISO） 缺氧 PET 进行成像。其更广泛应用的一个主要障碍是缺乏标准化的解释标准。我们试图为核医学医生制定和验证实用的解释标准和专门的培训方案，以解释 ¹⁸F-FMISO 缺氧 PET。方法：我们随机选择了 123 例参加 II 期试验的人瘤病毒阳性口咽癌患者，他们接受了 123 ^{例 18}F-FDG PET/CT 和 134 ^{例 18}F-FMISO PET/CT 扫描。四名没有 ¹⁸F-FMISO 经验的独立核医学医生阅读了扫描结果。由具有 ^{2 年 18}次 F-FMISO 经验的第五位核医学医师进行解释是参考标准。在初始指导和随后的专门培训后评估性能。如果 ¹⁸F-FMISO 摄取大于口地板摄取，则通过肉眼评估认为扫描对缺氧呈阳性。此外，确定 SUV_max 以评估使用肿瘤与背景比的定量评估是否有助于定义缺氧阳性。结果：初始指导后，视觉评估产生的平均敏感性和特异性分别为 77.3% 和 80.9%，读者间同意公平 （κ = 0.34）。经过专门训练，平均灵敏度和特异性提高到 97.6% 和 86.9%，几乎完全一致 （κ = 0.86）。定量评估估计最佳 SUV_最大比率阈值大于 1.2 以定义缺氧阳性，平均敏感性和特异性分别为 56.8% 和 95。9%，在初始指导后具有实质性的读者间协议 （κ = 0.66）。经过专门培训，平均灵敏度提高到 89.6%，而平均特异性保持在 95.3% 的高水平，读者间一致性接近完美 （κ = 0.86）。结论：没有 ¹⁸F-FMISO 缺氧 PET 阅读经验的核医学医生在使用特定解释标准进行专门培训后，读者之间的一致性大大提高。