磁共振弥散加权成像对鼻咽癌靶区勾画和复发转移预测的临床价值研究

目的 探讨磁共振弥散加权成像(DWMRI)能否预测鼻咽癌调强放疗后复发和转移以及判断靶区范围的价值。方法 回顾 2008年6月起初次调强放疗的鼻咽癌病历资料,选择有复发或转移 36例和无复发转移 36例作对照。对两组病例在DWMRI上测量其疗前肿瘤表观弥散系数(ADC值),并行成组t检验推测ADC值是否能预测鼻咽癌复发和转移。回顾分析局部区域复发病例放疗前MRI,从影像学角度分析DWMRI是否有助于判断靶区范围。结果 复发或转移组、对照组疗前ADC均值分别为(0.753±0.091)×10^－3、(0.793±0.094)×10^－3 mm²/s (t=－1.79,P=0.078)。影像学回顾分析显示DWMRI在低本底上突显了肿瘤侵犯范围,局部区域复发共 16例,15例疗前常规MRI弥散序列在病变范围上一致,1例复发患者DWMRI序列较常规序列更准确地预测了病变复发部位。结论 DWMRI结合常规MRI可更准确地判断鼻咽癌靶区范围,但其疗前ADC值的高低与鼻咽癌复发或转移并无关联。

The value of diffusion-weighted magnetic resonance imaging in gross tumor volume definition and tumor recurrence/metastasis prediction in nasopharyngeal carcinoma

Objective To investigate the value of diffusion-weighted magnetic resonance imaging (DWMRI) in gross tumor volume definition and localregional recurrence/distant metastasis prediction in nasopharyngeal carcinoma (NPC). Methods From Jun.2008 to Feb.2011, each of 36 patients with or without localregional recurrence and/or distant metastasis treated by intensity-modulated radiotherapy in our hospital was matched in this study. The difference of apparent diffusion coefficient (ADC) values between these two groups was compared by t-test method. The conventional MRI and DWMRI before treatment were centrally reviewed to evaluated whether DWMRI would benefit to the definition of gross tumor volume. Results The mean ADC value were (0.753±0.091)×10^－3 mm²/s and (0.793±0.094)×10^－3 mm²/s in treatment failure group and control group, respectively (t=－1.79,P=0.078). The extension of gross tumor volume were much more outstanding in DWMRI when compared to conventional MRI. DWMRIpredicted localregional recurrence more accuracy than conventional MRI in one patient. Conclusions
DWMRI is help to definition of gross tumor volume. The ADC value before radiotherapy can not predict the localregional recurrence and/or distant metastasis for nasopharyngeal carcinoma.