Nakajo Masatoyo, Jinguji Megumi, Shinaji Tetsuya, Nakajo Masayuki, Aoki Masaya, Tani Atsushi, Sato Masami, Yoshiura Takashi
1 Department of Radiology, Kagoshima University, Graduate School of Medical and Dental Sciences , Kagoshima , Japan.
2 Department of Nuclear Medicine, University of Würzburg , Würzburg , Germany.
Br J Radiol. 2018 Feb;91(1083):20170546. doi: 10.1259/bjr.20170546. Epub 2018 Jan 19.
To retrospectively investigate the standardized uptake value (SUV)-related and heterogeneous texture parameters individually and in combination for differentiating between low- and high-risk Fluorone-fludeoxyglucose (F-FDG)-avid thymic epithelial tumours (TETs) with positron emission tomography (PET)/CT.
SUV-related and 6 texture parameters (entropy, homogeneity, dissimilarity, intensity variability, size-zone variability and zone percentage) were compared between 11 low-risk and 23 high-risk TETs (metabolic tumour volume >10.0 cm and SUV ≥2.5). Diagnostic performance was evaluated by receiver operating characteristic analysis. The diagnostic value of combining SUV and texture parameters was examined by a scoring system.
High-risk TETs were significantly higher in SUVmax (p = 0.022), entropy (p = 0.038), intensity variability (p = 0.041) and size-zone variability (p = 0.045) than low-risk TETs. Diagnostic accuracies of these 4 parameters, dissimilarity and zone percentage which also showed significance in receiver operating characteristic analysis ranged between 64.7 and 73.5% without significant differences in AUC (range; 0.71 to 0.75) (p ≥ 0.05 each). Each parameter was scored as 0 (negative for high-risk) or 1 (positive for high-risk) according to each threshold criterion, then scores were summed [0 or 1 for low-risk TETs (median; 1); ≥2 for high-risk TETs (median; 4)]. The sensitivity, specificity and accuracy of detecting high-risk TETs were 100, 81.8 and 94.1%, respectively, with an AUC of 0.99.
The diagnostic performances of individual SUVmax and texture parameters were relatively low. However, combining these parameters can significantly increase diagnostic performance when differentiating between relatively large low- and high-risk F-FDG-avid TETs. Advances in knowledge: Combined use of SUVmax and texture parameters can significantly increase the diagnostic performance when differentiating between low- and high-risk TETs.
回顾性研究标准化摄取值（SUV）相关参数及异质性纹理参数单独及联合应用对正电子发射断层扫描（PET）/CT鉴别低风险和高风险氟代脱氧葡萄糖（F-FDG）摄取阳性胸腺上皮肿瘤（TET）的价值。
比较11例低风险和23例高风险TET（代谢肿瘤体积>10.0 cm且SUV≥2.5）的SUV相关参数和6种纹理参数（熵、均匀性、差异性、强度变异性、大小区域变异性和区域百分比）。采用受试者操作特征分析评估诊断性能。通过评分系统检验SUV和纹理参数联合的诊断价值。
高风险TET的SUVmax（p = 0.022）、熵（p = 0.038）、强度变异性（p = 0.041）和大小区域变异性（p = 0.045）显著高于低风险TET。这4个参数以及差异性和区域百分比在受试者操作特征分析中也显示出显著性，其诊断准确性在64.7%至73.5%之间，曲线下面积（AUC）无显著差异（范围：0.71至0.75）（各p≥0.05）。根据每个阈值标准，每个参数评分为0（高风险阴性）或1（高风险阳性），然后将分数相加[低风险TET为0或1（中位数；1）；高风险TET≥2（中位数；4）]。检测高风险TET的敏感性、特异性和准确性分别为100%、81.8%和94.1%，AUC为0.99。
单个SUVmax和纹理参数的诊断性能相对较低。然而，在鉴别相对较大的低风险和高风险F-FDG摄取阳性TET时，联合这些参数可显著提高诊断性能。知识进展：联合使用SUVmax和纹理参数在鉴别低风险和高风险TET时可显著提高诊断性能。
