Department of Radiology, University of Michigan Health System, Ann Arbor, Michigan.
Department of Radiology, University of Michigan Health System, Ann Arbor, Michigan.
Int J Radiat Oncol Biol Phys. 2022 Mar 1;112(3):704-714. doi: 10.1016/j.ijrobp.2021.10.006. Epub 2021 Oct 10.
Our purpose was to evaluate the accuracy of LI-RADS Treatment Response Algorithm (LR-TRA) for assessing the viability of hepatocellular carcinoma (HCC) treated with stereotactic body radiation therapy (SBRT), using explant pathology as the gold standard.
This retrospective study included patients who underwent SBRT for locoregional treatment of HCC between 2008 and 2019 with subsequent liver transplantation. Five radiologists independently assessed all treated lesions by using the LR-TRA. Imaging and posttransplant histopathology were compared. Lesions were categorized as either completely (100%) or incompletely (<100%) necrotic, and performance characteristics and predictive values for the LR-TR viable and nonviable categories were calculated for each reader. Interreader reliability was calculated using the Fleiss kappa test.
A total of 40 treated lesions in 26 patients (median age, 63 years [interquartile range, 59.4-65.5]; 23 men) were included. For lesions treated with SBRT, sensitivity for incomplete tumor necrosis across readers ranged between 71% and 86%, specificity between 85% and 96%, and positive predictive value between 86% and 92%, when the LR-TR equivocal category was treated as nonviable, accounting for subject clustering. When the LR-TR equivocal category was treated as viable, sensitivity of complete tumor necrosis for lesions treated with SBRT ranged from 88% to 96%, specificity from 71% to 93%, and negative predictive value from 85% to 96%. Interreader reliability was fair (k = 0.22; 95% confidence interval, 0.13-0.33). Although a loss of arterial phase hyperenhancement (APHE) was highly correlated with pathologically nonviable tumor on explant, almost half of the patients with APHE had pathologically nonviable tumor on explant.
LR-TRA v2018 performs well for predicting complete and incomplete necrosis in HCC treated with SBRT. In contrast to other locoregional therapies, the presence of APHE after SBRT does not always indicate viable tumor and suggests that observation may be an appropriate strategy for these patients.
本研究旨在评估 LI-RADS 治疗反应算法（LR-TRA）评估立体定向体部放射治疗（SBRT）治疗肝细胞癌（HCC）患者肿瘤活性的准确性，以肝移植后的组织病理学结果作为金标准。
本回顾性研究纳入了 2008 年至 2019 年间因局部区域 HCC 接受 SBRT 治疗并随后进行肝移植的患者。5 名放射科医生独立使用 LR-TRA 评估所有治疗后的病灶。对比影像学表现和移植后的组织病理学结果。将病灶分为完全（100%）或不完全（＜100%）坏死，并计算每位读者对 LR-TRA 有活力和无活力类别的诊断性能特征和预测值。采用 Fleiss κ 检验评估观察者间的可靠性。
共纳入 26 例患者的 40 个治疗病灶（中位年龄，63 岁[四分位数间距，59.4-65.5]；23 例男性）。对于接受 SBRT 治疗的病灶，当 LR-TRA 不确定类别被视为无活力时，5 名观察者的不完全肿瘤坏死的敏感性在 71%至 86%之间，特异性在 85%至 96%之间，阳性预测值在 86%至 92%之间，考虑到了受试者聚类的影响。当 LR-TRA 不确定类别被视为有活力时，接受 SBRT 治疗的完全肿瘤坏死的敏感性范围为 88%至 96%，特异性为 71%至 93%，阴性预测值为 85%至 96%。观察者间的可靠性为中等（κ=0.22；95%置信区间，0.13-0.33）。尽管动脉期增强（APHE）的丧失与肝移植后病理学上无活力的肿瘤高度相关，但近一半有 APHE 的患者在肝移植后存在无活力的肿瘤。
LR-TRA v2018 能够很好地预测 SBRT 治疗的 HCC 患者的完全和不完全坏死。与其他局部区域治疗方法不同，SBRT 后出现 APHE 并不总是表明肿瘤有活力，这表明对于这些患者，观察可能是一种合适的策略。
