Kanamoto Masayuki, Miyati Tosiaki, Terashima Kazuki, Suga Daisaku, Fuwa Nobukazu
Department of Radiology, University of Fukui Hospital, 23-3, Shimoaizuki, Matsuoka, Eiheiji-tyo, Yoshida-gun, Fukui, 910-1193, Japan.
Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, 5-11-80, Kodatsuno, Kanazawa, Ishikawa, 920-0942, Japan.
Radiol Phys Technol. 2016 Jul;9(2):233-9. doi: 10.1007/s12194-016-0354-5. Epub 2016 Apr 7.
We evaluated the state of hepatocellular carcinoma (HCC) and the liver after ion beam therapy by analyzing the apparent diffusion coefficient (ADC). In this retrospective study, we evaluated 13 HCC lesions in 10 patients who underwent magnetic resonance imaging before and after therapy. Diffusion-weighted imaging was performed with use of b values of 0, 150, and 800 s/mm(2). The ADC was determined for the tumor, irradiated liver, and normal liver. The maximum size of the tumor was measured, and reduction in tumor size was determined as a ratio of the maximum size of the diameter of the tumor. We compared the ADC before and after the therapy with the reduction in tumor size ratio. The reduction in tumor size ratio was compared with the ADCs of the tumors. The ADC of the tumor and the irradiated liver were significantly higher after therapy than before therapy. The ADC of the normal liver was not significantly different before and after therapy. The reduction ratio increased significantly (R = 0.73, P = 0.006) after therapy at the second follow-up when compared with after therapy at the first follow-up. No correlation was found between the reduction ratio and the ADC of the tumor in each follow-up. Inflammation of the liver occurs after treatment as a result of radiation doses from the ion beam, and the tumor reaches a state of necrosis. ADC value analysis provides a non-invasive assessment and yields focal information regarding the tumor and liver before and after ion beam therapy.
我们通过分析表观扩散系数（ADC）评估了离子束治疗后肝细胞癌（HCC）及肝脏的状态。在这项回顾性研究中，我们评估了10例接受治疗前后磁共振成像检查的患者的13个HCC病灶。使用b值为0、150和800 s/mm²进行扩散加权成像。测定肿瘤、受照射肝脏和正常肝脏的ADC。测量肿瘤的最大尺寸，并将肿瘤尺寸的缩小确定为肿瘤直径最大尺寸的比例。我们比较了治疗前后的ADC与肿瘤尺寸缩小比例。将肿瘤尺寸缩小比例与肿瘤的ADC进行比较。治疗后肿瘤和受照射肝脏的ADC显著高于治疗前。治疗前后正常肝脏的ADC无显著差异。与第一次随访治疗后相比，第二次随访治疗后缩小比例显著增加（R = 0.73，P = 0.006）。每次随访中，缩小比例与肿瘤的ADC之间均未发现相关性。离子束的辐射剂量导致治疗后肝脏出现炎症，肿瘤达到坏死状态。ADC值分析提供了一种非侵入性评估，并产生了有关离子束治疗前后肿瘤和肝脏的局部信息。
