Abstract：
Tumor cyst aspiration followed by Gamma Knife radiosurgery (GKRS) for large cystic brain metastases is a reasonable and effective management strategy. However, even with aspiration, the target lesion tends to exceed the dimensions of an ideal target for stereotactic radiosurgery. In this case, the local tumor control rate and the risk of complication might be a critical challenge. This study is aimed to investigate whether fractionated GKRS (f-GKRS) could solve these problems. Between May 2018 and April 2021, eight consecutive patients with nine lesions were treated with f-GKRS in five or ten sessions after cyst aspiration. The aspiration was repeated as needed throughout the treatment course to maintain the cyst size and shape. The patient characteristics, radiologic tumor response, and clinical course were reviewed using medical records. The mean follow-up duration was 10.2 (2-28) months. The mean pre-GKRS volume and maximum diameter were 16.7 (5-55.8) mL and 39.0 (31-79) mm, respectively. The mean tumor volume reduction achieved by aspiration was 55.4%. The tumor volume decreased for all lesions, and symptoms were alleviated in all patients. The median overall survival was 10.0 months, and the estimated 1-year survival rate was 41.7% (95% CI: 10.9-70.8%). The local tumor control rate was 100%. No irradiation-related adverse events were observed. f-GKRS for aspirated cystic brain metastasis is a safe, effective, and less invasive management option for large cystic brain metastases.
摘要：
肿瘤囊肿抽吸后伽玛刀放射外科（GKRS）治疗大囊性脑转移瘤是一种合理有效的治疗策略。然而,即使有抱负，目标病变往往超过立体定向放射外科理想目标的尺寸。在这种情况下,局部肿瘤控制率和并发症的风险可能是一个关键的挑战。本研究旨在探讨分馏GKRS（f-GKRS）是否可以解决这些问题。在2018年5月至2021年4月之间，囊肿抽吸后，连续8例9个病变的患者在5或10个疗程中接受了f-GKRS治疗。在整个治疗过程中根据需要重复抽吸以保持囊肿的大小和形状。病人的特点,放射学肿瘤反应，和临床过程使用医疗记录进行审查。平均随访时间为10.2(2～28)个月。前GKRS的平均体积和最大直径分别为16.7（5-55.8）mL和39.0（31-79）mm，分别。通过抽吸实现的平均肿瘤体积减少为55.4%。所有病变的肿瘤体积都减少了，所有患者症状均缓解。中位总生存期为10.0个月,估计的1年生存率为41.7％（95％CI：10.9-70.8％）。局部肿瘤控制率为100%。未观察到与辐射相关的不良事件。f-GKRS用于吸入性囊性脑转移是安全的，有效,大囊性脑转移的侵入性较小的管理选择。
