Zhou Nan, Guo Tingting, Zheng Huanhuan, Pan Xia, Chu Chen, Dou Xin, Li Ming, Liu Song, Zhu Lijing, Liu Baorui, Chen Weibo, He Jian, Yan Jing, Zhou Zhengyang, Yang Xiaofeng
Department of Radiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China.
Department of Radiology, Nanjing Drum Tower Hospital, Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210008, China.
Oncotarget. 2017 Jul 26;8(41):70226-70238. doi: 10.18632/oncotarget.19602. eCollection 2017 Sep 19.
We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased ( < 0.001, = 0.001, and < 0.001, respectively), but all other ADC histogram parameters increased (all < 0.001, except = 0.006 for standard deviation [SD]). From time point 2 to 3, parotid volume continued to decrease ( = 0.022), and SD, 75 and 90 percentiles continued to increase ( = 0.024, 0.010, and 0.006, respectively). Early change rates of parotid ADC, ADC, kurtosis, and 25, 50, 75, 90 percentiles (from time point 1 to 2) correlated with late parotid atrophy rate (from time point 1 to 3) (all < 0.05). Multiple linear regression analysis revealed correlations among parotid volume, time point, and ADC histogram parameters. Early mean change rates for bilateral parotid SD and ADC could predict late xerostomia degrees at seven months after radiotherapy (three months after time point 3) with AUC of 0.781 and 0.818 ( = 0.014, 0.005, respectively). ADC histogram parameters were reproducible (intraclass correlation coefficient, 0.830 - 0.999). ADC histogram analysis could be used to evaluate radiation-induced parotid damage noninvasively, and predict late xerostomia degrees of NPC patients treated with radiotherapy.
我们研究了表观扩散系数（ADC）直方图分析，以评估接受放射治疗的鼻咽癌（NPC）患者的放射性腮腺损伤，并预测口干程度。在放疗前2周（时间点1）、放疗后1个月（时间点2）和放疗后4个月（时间点3）对NPC患者的双侧腮腺进行成像。从时间点1到2，腮腺体积、偏度和峰度下降（分别为<0.001、=0.001和<0.001），但所有其他ADC直方图参数增加（除标准差[SD]的=0.006外，均<0.001）。从时间点2到3，腮腺体积继续下降（=0.022），SD、75%和90%百分位数继续增加（分别为=0.024、0.010和0.006）。腮腺ADC、ADC、峰度以及25%、50%、75%、90%百分位数的早期变化率（从时间点1到2）与晚期腮腺萎缩率（从时间点1到3）相关（均<0.05）。多元线性回归分析揭示了腮腺体积、时间点和ADC直方图参数之间的相关性。双侧腮腺SD和ADC的早期平均变化率可以预测放疗后7个月（时间点3后3个月）的晚期口干程度，曲线下面积分别为0.781和0.818（分别为=0.014、0.005）。ADC直方图参数具有可重复性（组内相关系数，0.830 - 0.999）。ADC直方图分析可用于无创评估放射性腮腺损伤，并预测接受放疗的NPC患者的晚期口干程度。
