Phase Ⅱ clinical trial of hippocampal-sparing prophylactic cranial irradiation in patients with small cell lung cancer
Dong Xin, Zhou Zongmei, Liu Xuan, Wang Wenqing, Xiao Zefen, Zhang Tao, Wang Xin, Feng Qinfu, Bi Nan, Zhai Yirui, Liang Jun, Deng Lei, Chen Dongfu, Li Tao, Hui Zhouguang, Wang Xiaozhen, Lv Jima, Wang Lvhua, Li Yexiong
Department of Radiation Oncology,National Cancer Centre/Cancer Hospital,Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing 100021,China
Abstract： Objective To evaluate the dose distribution and clinical efficacy of hippocampal-sparing prophylactic cranial irradiation (HS-PCI) in patients with small cell lung cancer by using helical tomotherapy. Methods Clinical data of 49 patients with small cell lung cancer receiving HS-PCI using helical tomotherapy in Cancer Hospital between 2014 and 2017 were retrospectively analyzed. All patients received brain MRI to exclude the possibility of brain metastasis within 1 month after standard surgery or radio-and chemo-therapy. The prescription dose was 95% PTV,25 Gy in 10 fractions. The adverse reactions and cognitive functions of patients were observed before,6 months and 1 year after treatment,and the dose distribution in the hippocampal gyrus,survival rate and brain metastasis rate were analyzed. Results The median follow-up time was 16 months. The average dose in the hippocampal gyrus was 7.23 Gy and 8.46 Gy in the reduction region,which was reduced by 71.88% and 66.16% compared with the prescription dose. The maximum dose in the hippocampal gyrus was 10.66 Gy and 15.43 Gy in the reduction region. Among 49 patients,8 died,the 1-year survival rate was 85.1% and the 2-year survival rate was 70.3%.Nine patients (18.3%) had brain metastases,and one of them with extensive multiple brain metastases (n=13) presented with metastasis adjacent to the hippocampal gyrus. The main adverse reactions included mild headache,dizziness and brain edema,whereas no ≥ grade 2 adverse reactions occurred. At 6 months after treatment,the HVLT-R score was significantly decreased,and declined by 6.78% at 12 months after treatment. The HVLT-R scores did not significantly differ in patients without brain metastasis before and 12 months after treatment (P>0.05). Conclusion Application of HS-PCI using helical tomotherapy meets the dose requirement,effectively protects the cognitive function and yields slight adverse reactions.
Dong Xin,Zhou Zongmei,Liu Xuan et al. Phase Ⅱ clinical trial of hippocampal-sparing prophylactic cranial irradiation in patients with small cell lung cancer[J]. Chinese Journal of Radiation Oncology, 2018, 27(7): 638-642.
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2018, Vol. 27 
