Zhang Youming, Yi Xiaoping, Gao Jianming, Li Li, Liu Lizhi, Qiu Ting, Zhang Jinlei, Zhang Yuanchao, Liao Weihua
Department of Radiology, Xiangya Hospital, Central South University, Changsha, China.
State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China.
Front Oncol. 2019 Jul 3;9:567. doi: 10.3389/fonc.2019.00567. eCollection 2019.
Radiation encephalopathy (RE) is deemed to be a disease induced only by radiotherapy (RT), with the effects of chemotherapeutic agents on the brains of nasopharyngeal carcinoma (NPC) patients being largely overlooked. In this study, we investigated structural and functional brain alterations in NPC patients following RT with or without chemotherapy. Fifty-six pre-RT, 37 post-RT, and 108 post-CCRT (concomitant chemo-radiotherapy) NPC patients were enrolled in this study. A surface-based local gyrification index (LGI) was obtained from high resolution MRI and was used to evaluate between-group differences in cortical folding. Seed-based functional connectivity (FC) analysis of resting-state fMRI data was also conducted to investigate the functional significance of the cortical folding alterations. Compared with the Pre-RT group, patients in the Post-CCRT group showed LGI reductions in widespread brain regions including the bilateral temporal lobes, insula, frontal lobes, and parietal lobes. Compared with the Post-RT group, patients in the Post-CCRT group showed LGI reductions in the right insula, which extended to the adjacent frontal lobe. Seed-based FC analysis showed that patients in the Post-CCRT group had lower FC between the insula and the left middle frontal gyrus than patients in the Pre-RT group. The follow-up results showed that patients in the Post-CCRT group had a much higher RE incidence rate (20.4%) than patients in the Post-RT group (2.7%; = 0.01). These findings indicate that chemotherapy potentially facilitated the occurrence of RE in NPC patients who underwent radiotherapy.
放射性脑病（RE）被认为是一种仅由放射治疗（RT）诱发的疾病，而化疗药物对鼻咽癌（NPC）患者大脑的影响在很大程度上被忽视了。在本研究中，我们调查了接受或未接受化疗的NPC患者在放疗后的大脑结构和功能改变。本研究纳入了56例放疗前、37例放疗后和108例同步放化疗（CCRT）后的NPC患者。从高分辨率MRI中获得基于表面的局部脑回指数（LGI），并用于评估组间皮质折叠的差异。还对静息态功能磁共振成像数据进行了基于种子点的功能连接（FC）分析，以研究皮质折叠改变的功能意义。与放疗前组相比，同步放化疗后组患者在包括双侧颞叶、岛叶、额叶和顶叶在内的广泛脑区LGI降低。与放疗后组相比，同步放化疗后组患者右侧岛叶LGI降低，并延伸至相邻额叶。基于种子点的FC分析显示，同步放化疗后组患者岛叶与左侧额中回之间的FC低于放疗前组患者。随访结果显示，同步放化疗后组患者的RE发病率（20.4%）远高于放疗后组患者（2.7%；P = 0.01）。这些发现表明，化疗可能促进了接受放疗的NPC患者发生RE。
