我们研究了剂量节约和回避技术的调强放射治疗对局部颅内生殖细胞瘤的儿科患者的影响。我们还回顾了有关与晚期神经认知后遗症有关的现代辐照技术的文献。在松果体前部的第三脑室有局部颅内生殖细胞瘤的患者接受了剂量节省的强度调制放射治疗。将该计划与放射肿瘤学家关于危险器官和剂量限制的指南进行比较,以进行剂量测定分析。患者单独接受放射治疗。使用剂量雕刻计划,总剂量以2.0Gy部分输送到原发性肿瘤,以1.4Gy部分输送到整个脑室,以37Gy部分输送到整个脑室。剂量学分析表明,剂量节约的调强放射治疗对整个大脑的剂量减少,颞叶,海马,耳蜗,和视神经.经过22个月的随访,患者的无失败生存率为100%,放射治疗过程中无不良事件.采用剂量节约和回避技术的调强放射治疗可以省去边缘电路,中枢神经系统,松果体生殖细胞肿瘤的海马体。该技术减少了输送到未受累的正常脑组织的积分剂量,并可能减少由头颅放疗引起的晚期神经认知后遗症。
We examined the effects of intensity-modulated radiation therapy with dose-sparing and avoidance technique on a pediatric patient with localized intracranial germinoma. We also reviewed the literature regarding modern irradiation techniques in relation to late neurocognitive sequelae. A patient with a localized intracranial germinoma in the third ventricle anterior to the pineal gland received a dose-sparing intensity-modulated radiation therapy. The planning was compared to the radiation oncologist\'s guide of organs at risk and dose constraints for dosimetric analyses. The patient received radiation therapy alone. The total dose was 54Gy delivered in 2.0Gy fractions to the primary tumour and 37Gy in 1.4Gy fractions to whole ventricles using a dose-sculpting plan. Dosimetry analyses showed that dose-sparing intensity-modulated radiation therapy delivered reduced doses to the whole brain, temporal lobes, hippocampi, cochleae, and optic nerves. With a follow-up of 22 months, failure-free survival was 100% for the patient and no adverse events during radiation treatment process. Intensity-modulated radiation therapy with dose sparing and avoidance technique can spare the limbic circuit, central nervous system, and hippocampus for pineal germ cell tumours. This technique reduces the integral dose delivered to the uninvolved normal brain tissues and may reduce late neurocognitive sequelae caused by cranial radiotherapy.