Kang Tae Wook, Kim Seong Hyun, Lee Jisun, Kim Ah Yeong, Jang Kyung Mi, Choi Dongil, Kim Min Ji
Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Ilwon-Ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Ilwon-Ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
Eur J Radiol. 2015 Nov;84(11):2089-96. doi: 10.1016/j.ejrad.2015.08.007. Epub 2015 Aug 20.
To compare computed tomography (CT) findings in patients with pancreatic metastasis from renal cell carcinoma (pRCC) and patients with hypervascular pancreatic neuroendocrine tumour (pNET) with a focus on the relative percentage washout (RPW).
We evaluated 16 patients with 37 pRCCs and 28 patients with 31 hypervascular pNETs using a protocol consisting of arterial and portal phase CT. Imaging findings were analyzed for comparison between the two groups. The RPW of each tumour using biphasic CT was obtained by two observers for evaluation of diagnostic performance. Interobserver agreement of each value and optimal cut-off level of RPW for discrimination between groups were evaluated.
Tumour multiplicity showed significant difference in both groups. The mean RPW of the pRCC group (observer 1, 27.0%; observer 2, 29.4%) was significantly higher than that of the pNET group (observer 1, 0.5%; observer 2, 3.2%) (p<0.001 for each observer). Interobserver agreement for both attenuation values and RPWs was excellent. A RPW value of 19% was selected as the optimal cut-off for pRCC determination, and showed good performance (accuracy 83.8%, sensitivity 83.8%, and specificity 83.9%).
With multiplicity, RPW of the tumour on CT could be helpful for differentiating pRCCs from hypervascular pNETs.
比较肾细胞癌胰腺转移（pRCC）患者与富血供胰腺神经内分泌肿瘤（pNET）患者的计算机断层扫描（CT）表现，重点关注相对百分比洗脱（RPW）。
我们采用动脉期和门静脉期CT方案评估了16例患有37个pRCC的患者和28例患有31个富血供pNET的患者。分析影像学表现以比较两组之间的差异。由两名观察者通过双期CT获得每个肿瘤的RPW，以评估诊断性能。评估每个值的观察者间一致性以及用于区分两组的RPW的最佳截断水平。
两组肿瘤的多发性均有显著差异。pRCC组的平均RPW（观察者1为27.0%；观察者2为29.4%）显著高于pNET组（观察者1为0.5%；观察者2为3.2%）（每位观察者的p<0.001）。衰减值和RPW的观察者间一致性均极佳。选择19%的RPW值作为pRCC判定的最佳截断值，其表现良好（准确率83.8%，敏感性83.8%，特异性83.9%）。
结合肿瘤的多发性，CT上肿瘤的RPW有助于鉴别pRCC和富血供pNET。
