Abstract：
BACKGROUND: The so-called radiation-induced glioma (RIG, a secondary glioma after cranial irradiation), is a serious late effect after cranial radiation therapy. The clinical characteristics of and ideal treatment for these tumors are unclear. We analyzed our case series and conducted a comprehensive literature review to reveal the precise characteristics of RIGs.
METHODS: We analyzed the cases of six patients with RIGs treated at our institution and 354 patients with RIGs from the literature. The latency period from irradiation to the development of each RIG and the median overall survival of the patients were subjected to Kaplan-Meier analyses. Spearman\'s correlation test was used to determine the relationship between age at irradiation and the latency period.
RESULTS: The mean age of the 360 patients at the development of RIG was 27.42 ± 17.87 years. The mean latency period was 11.35 ± 8.58 years. Multiple gliomas were observed in 28.4%. WHO grade 3 and 4 RIGs accounted for 93.3%. The latency periods were significant shorter in the higher WHO grade group (p = 0.0366) and the concomitant systemic chemotherapy group (p < 0.0001). Age at irradiation was negatively associated with the latency period (r =- 0.2287, p = 0.0219). The patients treated with radiotherapy achieved significantly longer survival compared to those treated without radiotherapy (p = 0.0011).
CONCLUSIONS: Development in younger age, multiplicity, and high incidence of grade 3 and 4 are the clinical characteristics of RIGs. Cranial irradiation at older ages and concomitant chemotherapy were associated with shorter latency for the development of RIG. Radiation therapy may be the feasible treatment option despite radiation-induced gliomas.
METHODS: We analyzed the cases of six patients with RIGs treated at our institution and 354 patients with RIGs from the literature. The latency period from irradiation to the development of each RIG and the median overall survival of the patients were subjected to Kaplan-Meier analyses. Spearman\'s correlation test was used to determine the relationship between age at irradiation and the latency period.
RESULTS: The mean age of the 360 patients at the development of RIG was 27.42 ± 17.87 years. The mean latency period was 11.35 ± 8.58 years. Multiple gliomas were observed in 28.4%. WHO grade 3 and 4 RIGs accounted for 93.3%. The latency periods were significant shorter in the higher WHO grade group (p = 0.0366) and the concomitant systemic chemotherapy group (p < 0.0001). Age at irradiation was negatively associated with the latency period (r =- 0.2287, p = 0.0219). The patients treated with radiotherapy achieved significantly longer survival compared to those treated without radiotherapy (p = 0.0011).
CONCLUSIONS: Development in younger age, multiplicity, and high incidence of grade 3 and 4 are the clinical characteristics of RIGs. Cranial irradiation at older ages and concomitant chemotherapy were associated with shorter latency for the development of RIG. Radiation therapy may be the feasible treatment option despite radiation-induced gliomas.
摘要：
背景：所谓的辐射诱导的神经胶质瘤（RIG，颅骨照射后的继发性神经胶质瘤)，是头颅放射治疗后的严重晚期效应。这些肿瘤的临床特征和理想的治疗方法尚不清楚。我们分析了我们的案例系列，并进行了全面的文献综述，以揭示RIGs的确切特征。
方法：我们分析了在我们机构治疗的6例RIG患者和文献中的354例RIG患者的病例。对从照射到每个RIG发展的潜伏期和患者的中位总生存期进行Kaplan-Meier分析。Spearman相关性检验用于确定照射年龄与潜伏期之间的关系。
结果：360名患者在RIG发展时的平均年龄为27.42±17.87岁。平均潜伏期为11.35±8.58年。28.4%的患者出现多发性胶质瘤。WHO3级和4级RIG占93.3%。WHO分级较高的组（p=0.0366）和伴随的全身化疗组（p<0.0001）的潜伏期明显较短。照射年龄与潜伏期呈负相关（r=-0.2287，p=0.0219）。与未接受放射治疗的患者相比，接受放射治疗的患者的生存期明显更长（p=0.0011）。
结论：年轻时的发育，多重性,3级和4级的高发病率是RIG的临床特征。年龄较大的颅内照射和伴随的化疗与RIG发展的潜伏期较短有关。尽管有辐射诱发的神经胶质瘤，但放射治疗可能是可行的治疗选择。
方法：我们分析了在我们机构治疗的6例RIG患者和文献中的354例RIG患者的病例。对从照射到每个RIG发展的潜伏期和患者的中位总生存期进行Kaplan-Meier分析。Spearman相关性检验用于确定照射年龄与潜伏期之间的关系。
结果：360名患者在RIG发展时的平均年龄为27.42±17.87岁。平均潜伏期为11.35±8.58年。28.4%的患者出现多发性胶质瘤。WHO3级和4级RIG占93.3%。WHO分级较高的组（p=0.0366）和伴随的全身化疗组（p<0.0001）的潜伏期明显较短。照射年龄与潜伏期呈负相关（r=-0.2287，p=0.0219）。与未接受放射治疗的患者相比，接受放射治疗的患者的生存期明显更长（p=0.0011）。
结论：年轻时的发育，多重性,3级和4级的高发病率是RIG的临床特征。年龄较大的颅内照射和伴随的化疗与RIG发展的潜伏期较短有关。尽管有辐射诱发的神经胶质瘤，但放射治疗可能是可行的治疗选择。
