The increasing prevalence of brain metastases in cancer patients due to longer life expectancy and improvements in neuroimaging highlights the need for effective local treatments. Despite advancements in systemic targeted therapies, their low blood–brain barrier (BBB) penetrance limits their intracranial efficacy. Stereotactic radiosurgery (SRS) has largely supplanted whole-brain radiation therapy (WBRT) for patients with up to 10 brain lesions due to superior neurocognitive outcomes and high local control. While single-fraction SRS provides low radiation toxicity with smaller lesions, high-volume metastases necessitate doses above tolerance limits to achieve comparable local control. As tumor volume increases, the number of tumor cells also increases, requiring higher doses of radiation than the maximum tolerated doses reported in the RTOG 9005 study to achieve tumor control. Hypo-fractionated SRS (HySRS) permits the delivery of high radiation doses over 2–5 fractions, thus mitigating the risk of radiation toxicity while maintaining high local control. This review presents the available evidence and ongoing clinical trials on HySRS for the management of brain metastases.
随着癌症患者预期寿命延长及神经影像学技术的进步，脑转移瘤发病率日益增高，凸显出对有效局部治疗手段的需求。尽管全身靶向治疗取得进展，但其较低的血脑屏障穿透率限制了颅内疗效。对于病灶数量不超过10个的患者，立体定向放射外科因其更优的神经认知结局和较高的局部控制率，已基本取代全脑放疗。单次分割立体定向放射外科对小病灶放射毒性较低，但大体积转移瘤需要超过耐受极限的剂量才能达到相当的局部控制效果。随着肿瘤体积增大，肿瘤细胞数量相应增加，为实现肿瘤控制所需辐射剂量已超过RTOG 9005研究报告的最大耐受剂量。大分割立体定向放射外科通过2-5次分割实现高剂量照射，在维持高局部控制率的同时有效降低放射毒性风险。本综述系统阐述了大分割立体定向放射外科治疗脑转移瘤的现有证据及正在进行中的临床试验。
Hypo-Fractionated Stereotactic Radiosurgery for the Management of Brain Metastases
肿瘤(癌症)患者之家