Abstract：
OBJECTIVE: Two-staged gamma knife surgery (GKS) is a method that may extend the upper tumor volume limit for using GKS in the management of brain metastases. However, the safety of treating very large posterior fossa lesions with this technique has not been well demonstrated. Therefore, we analyzed our experience in treating cerebellar metastases larger than 12 cm3 with two-staged GKS.
METHODS: Four consecutive patients harboring 12 to 30 cm3 cerebellar metastases scheduled two-staged GKS were included in the study, and all but one patient completed the treatment. The treatment doses were 10-13 Gy. All patients were followed with regular MR imaging and clinical assessments, and the tumor volumes were measured on all treatment and follow-up images.
RESULTS: Tumor progression was not demonstrated in any of the patients. Tumor volumes decreased by, on average, more than half between the two stages. The median survival was 22 months, and no patient died due to intracranial tumor progression. Peritumoral edema at the first GKS resolved in all patients, replaced by asymptomatic mild T2 changes in two of them not requiring any treatment. No radiation-induced complication has developed thus far.
CONCLUSIONS: Staged GKS seems to be a feasible management option for very large cerebellar metastases.
METHODS: Four consecutive patients harboring 12 to 30 cm3 cerebellar metastases scheduled two-staged GKS were included in the study, and all but one patient completed the treatment. The treatment doses were 10-13 Gy. All patients were followed with regular MR imaging and clinical assessments, and the tumor volumes were measured on all treatment and follow-up images.
RESULTS: Tumor progression was not demonstrated in any of the patients. Tumor volumes decreased by, on average, more than half between the two stages. The median survival was 22 months, and no patient died due to intracranial tumor progression. Peritumoral edema at the first GKS resolved in all patients, replaced by asymptomatic mild T2 changes in two of them not requiring any treatment. No radiation-induced complication has developed thus far.
CONCLUSIONS: Staged GKS seems to be a feasible management option for very large cerebellar metastases.
摘要：
目的：两阶段伽玛刀手术（GKS）是一种可能延长使用GKS治疗脑转移瘤的肿瘤体积上限的方法。然而,使用这种技术治疗非常大的后颅窝病变的安全性尚未得到很好的证明。因此,我们分析了我们使用两阶段GKS治疗大于12cm3的小脑转移的经验。
方法：本研究纳入了4例连续有12至30cm3小脑转移的患者，除一名患者外，所有患者都完成了治疗。治疗剂量为10-13Gy。所有患者均接受常规MR成像和临床评估，在所有治疗和随访图像上测量肿瘤体积。
结果：所有患者均未出现肿瘤进展。肿瘤体积减少，平均而言,两个阶段之间的一半以上。中位生存期为22个月,无患者因颅内肿瘤进展而死亡。所有患者首次GKS时肿瘤周围水肿消退，取而代之的是无症状的轻度T2变化，其中两个不需要任何治疗。到目前为止，尚未出现辐射引起的并发症。
结论：分期GKS似乎是非常大的小脑转移的可行管理选择。
方法：本研究纳入了4例连续有12至30cm3小脑转移的患者，除一名患者外，所有患者都完成了治疗。治疗剂量为10-13Gy。所有患者均接受常规MR成像和临床评估，在所有治疗和随访图像上测量肿瘤体积。
结果：所有患者均未出现肿瘤进展。肿瘤体积减少，平均而言,两个阶段之间的一半以上。中位生存期为22个月,无患者因颅内肿瘤进展而死亡。所有患者首次GKS时肿瘤周围水肿消退，取而代之的是无症状的轻度T2变化，其中两个不需要任何治疗。到目前为止，尚未出现辐射引起的并发症。
结论：分期GKS似乎是非常大的小脑转移的可行管理选择。
