Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
J Nucl Med. 2024 Oct 1;65(10):1526-1532. doi: 10.2967/jnumed.124.267775.
Tumor hypoxia, an integral biomarker to guide radiotherapy, can be imaged with F-fluoromisonidazole (F-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 F-FMISO hypoxia PET. We randomly selected 123 patients with human papillomavirus-positive oropharyngeal cancer enrolled in a phase II trial who underwent 123 F-FDG PET/CT and 134 F-FMISO PET/CT scans. Four independent nuclear medicine physicians with no F-FMISO experience read the scans. Interpretation by a fifth nuclear medicine physician with over 2 decades of F-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 F-FMISO uptake was greater than floor-of-mouth uptake. Additionally, SUV was determined to evaluate whether quantitative assessment using tumor-to-background ratios could be helpful to define hypoxia positivity. 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 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). Nuclear medicine physicians without F-FMISO hypoxia PET reading experience demonstrate much improved interreader agreement with dedicated training using specific interpretation criteria.
肿瘤乏氧是指导放疗的一个重要生物标志物，可以通过 F-氟代硝基咪唑（F-FMISO）乏氧 PET 进行成像。其广泛应用的一个主要障碍是缺乏标准化的解释标准。我们旨在为核医学医师开发和验证实用的解释标准和专门的培训方案，以解读 F-FMISO 乏氧 PET。我们随机选择了 123 名接受过 123 F-FDG PET/CT 和 134 F-FMISO PET/CT 扫描的人乳头瘤病毒阳性口咽癌二期试验患者。四位没有 F-FMISO 经验的核医学医师独立阅读这些扫描图像。一位具有 20 多年 F-FMISO 经验的核医学医师的解读被作为参考标准。在初始指导和随后的专门培训后评估了性能。如果 F-FMISO 摄取量大于口腔底部摄取量，则通过视觉评估将扫描结果判断为缺氧阳性。此外，SUV 也被确定用于评估使用肿瘤与背景的比值进行定量评估是否有助于确定缺氧阳性。在初始指导后，视觉评估的平均敏感性和特异性分别为 77.3%和 80.9%，具有中等的读者间一致性（κ=0.34）。经过专门培训后，平均敏感性和特异性提高到 97.6%和 86.9%，具有几乎完美的一致性（κ=0.86）。使用估计最佳 SUV 比值阈值（大于 1.2）定义缺氧阳性的定量评估，在初始指导后，平均敏感性和特异性分别为 56.8%和 95.9%，具有较大的读者间一致性（κ=0.66）。经过专门培训后，平均敏感性提高到 89.6%，而特异性仍保持在 95.3%，具有近乎完美的读者间一致性（κ=0.86）。没有 F-FMISO 乏氧 PET 阅读经验的核医学医师在使用特定的解释标准进行专门培训后，读者间的一致性有了很大的提高。
