Abstract：
OBJECTIVE: To investigate the variability and diagnostic efficacy of respiratory-gated (RG) PET/CT based radiomics features compared to ungated (UG) PET/CT in the differentiation of non-small cell lung cancer (NSCLC) and benign lesions.
METHODS: 117 patients with suspected lung lesions from March 2020 to May 2021 and consent to undergo UG PET/CT and chest RG PET/CT (including phase-based quiescent period gating, pQPG and phase-matched 4D PET/CT, 4DRG) were prospectively included. 377 radiomics features were extracted from PET images of each scan. Paired t test was used to compare UG and RG features for inter-scan variability analysis. We developed three radiomics models with UG and RG features (i.e. UGModel, pQPGModel and 4DRGModel). ROC curves were used to compare diagnostic efficiencies, and the model-level comparison of diagnostic value was performed by five-fold cross-validation. A P value < 0.05 was considered as statistically significant.
RESULTS: A total of 111 patients (average age ± standard deviation was 59.1 ± 11.6 y, range, 29 - 88 y, and 63 were males) with 209 lung lesions were analyzed for features variability and the subgroup of 126 non-metastasis lesions in 91 patients without treatment before PET/CT were included for diagnosis analysis. 101/377 (26.8 %) 4DRG features and 82/377 (21.8 %) pQPG features showed significant difference compared to UG features (both P<0.05). 61/377 (16.2 %) and 59/377 (15.6 %) of them showed significantly better discriminant ability (ΔAUC% (i.e. (AUCRG - AUCUG) / AUCUG×100 %) > 0 and P<0.05) in malignant recognition, respectively. For the model-level comparison, 4DRGModel achieved the highest diagnostic efficacy (sen 73.2 %, spe 87.3 %) compared with UGModel (sen 57.7 %, spe 76.4 %) and pQPGModel (sen 63.4 %, spe 81.8 %).
CONCLUSIONS: RG PET/CT performs better in the quantitative assessment of metabolic heterogeneity for lung lesions and the subsequent diagnosis in patients with NSCLC compared with UG PET/CT.
METHODS: 117 patients with suspected lung lesions from March 2020 to May 2021 and consent to undergo UG PET/CT and chest RG PET/CT (including phase-based quiescent period gating, pQPG and phase-matched 4D PET/CT, 4DRG) were prospectively included. 377 radiomics features were extracted from PET images of each scan. Paired t test was used to compare UG and RG features for inter-scan variability analysis. We developed three radiomics models with UG and RG features (i.e. UGModel, pQPGModel and 4DRGModel). ROC curves were used to compare diagnostic efficiencies, and the model-level comparison of diagnostic value was performed by five-fold cross-validation. A P value < 0.05 was considered as statistically significant.
RESULTS: A total of 111 patients (average age ± standard deviation was 59.1 ± 11.6 y, range, 29 - 88 y, and 63 were males) with 209 lung lesions were analyzed for features variability and the subgroup of 126 non-metastasis lesions in 91 patients without treatment before PET/CT were included for diagnosis analysis. 101/377 (26.8 %) 4DRG features and 82/377 (21.8 %) pQPG features showed significant difference compared to UG features (both P<0.05). 61/377 (16.2 %) and 59/377 (15.6 %) of them showed significantly better discriminant ability (ΔAUC% (i.e. (AUCRG - AUCUG) / AUCUG×100 %) > 0 and P<0.05) in malignant recognition, respectively. For the model-level comparison, 4DRGModel achieved the highest diagnostic efficacy (sen 73.2 %, spe 87.3 %) compared with UGModel (sen 57.7 %, spe 76.4 %) and pQPGModel (sen 63.4 %, spe 81.8 %).
CONCLUSIONS: RG PET/CT performs better in the quantitative assessment of metabolic heterogeneity for lung lesions and the subsequent diagnosis in patients with NSCLC compared with UG PET/CT.
摘要：
目的：探讨基于呼吸门控（RG）PET/CT的影像组学特征与非门控（UG）PET/CT在非小细胞肺癌（NSCLC）和良性病变鉴别诊断中的差异和诊断效能。
方法：从2020年3月至2021年5月，117例疑似肺部病变的患者，并同意接受UGPET/CT和胸部RGPET/CT（包括基于相位的静止期门控，pQPG和相位匹配的4DPET/CT，4DRG）被前瞻性地包括在内。从每次扫描的PET图像中提取377个影像组学特征。使用配对t检验比较UG和RG特征以进行扫描间变异性分析。我们开发了三种具有UG和RG功能的影像组学模型(即UGModel，pQPGModel和4DRGModel)。ROC曲线用于比较诊断效率，通过5倍交叉验证进行模型级诊断价值比较.P值<0.05被认为是统计学上显著的。
结果：共111例患者（平均年龄±标准差为59.1±11.6岁，范围,29-88y，分析了63例男性），209例肺部病变的特征变异性，并纳入了PET/CT之前未经治疗的91例患者中126例非转移病变的亚组进行了诊断分析。101/377(26.8%)的4DRG特征和82/377(21.8%)的pQPG特征与UG特征相比差异显著(均P<0.05)。其中61/377(16.2%)和59/377(15.6%)在恶性识别中表现出明显更好的判别能力(ΔAUC%(即(AUCRG-AUCUG)/AUCUG×100%)>0,P<0.05),分别。对于模型级别的比较，4DRG模型实现了最高的诊断效能(森73.2%，spe87.3%)与UGModel(森57.7%，spe76.4%)和pQPGModel(sen63.4%，spe81.8%）。
结论：与UGPET/CT相比，RGPET/CT在肺部病变代谢异质性的定量评估以及NSCLC患者的后续诊断中表现更好。
方法：从2020年3月至2021年5月，117例疑似肺部病变的患者，并同意接受UGPET/CT和胸部RGPET/CT（包括基于相位的静止期门控，pQPG和相位匹配的4DPET/CT，4DRG）被前瞻性地包括在内。从每次扫描的PET图像中提取377个影像组学特征。使用配对t检验比较UG和RG特征以进行扫描间变异性分析。我们开发了三种具有UG和RG功能的影像组学模型(即UGModel，pQPGModel和4DRGModel)。ROC曲线用于比较诊断效率，通过5倍交叉验证进行模型级诊断价值比较.P值<0.05被认为是统计学上显著的。
结果：共111例患者（平均年龄±标准差为59.1±11.6岁，范围,29-88y，分析了63例男性），209例肺部病变的特征变异性，并纳入了PET/CT之前未经治疗的91例患者中126例非转移病变的亚组进行了诊断分析。101/377(26.8%)的4DRG特征和82/377(21.8%)的pQPG特征与UG特征相比差异显著(均P<0.05)。其中61/377(16.2%)和59/377(15.6%)在恶性识别中表现出明显更好的判别能力(ΔAUC%(即(AUCRG-AUCUG)/AUCUG×100%)>0,P<0.05),分别。对于模型级别的比较，4DRG模型实现了最高的诊断效能(森73.2%，spe87.3%)与UGModel(森57.7%，spe76.4%)和pQPGModel(sen63.4%，spe81.8%）。
结论：与UGPET/CT相比，RGPET/CT在肺部病变代谢异质性的定量评估以及NSCLC患者的后续诊断中表现更好。
