Gamma Knife House, Chiba Cerebral and Cardiovascular Center, 575 Tsurumai, Ichihara, Chiba, 2900512, Japan.
Tokyo Gamma Unit Center, Tsukiji Neurological Clinic, Tokyo, Japan.
J Neurooncol. 2020 Mar;147(1):237-246. doi: 10.1007/s11060-020-03421-y. Epub 2020 Feb 5.
Stereotactic radiosurgery (SRS) is typically considered for patients who cannot undergo surgical resection for large (> 10 cm) brain metastases (BMs). Staged SRS requires adaptive planning during each stage of the irradiation period for improved tumor control and reduced radiation damage. However, there has been no study on the tumor reduction rates of this method. We evaluated the outcomes of two-stage SRS across multiple primary cancer types.
We analyzed 178 patients with 182 large BMs initially treated with two-stage SRS. The primary cancers included breast (BC), non-small cell lung (NSCLC), and gastrointestinal tract cancers (GIC). We analyzed the overall survival (OS), neurological death, systemic death (SD), tumor progression (TP), tumor recurrence (TR), radiation necrosis (RN), and the tumor reduction rate during both stages.
The median survival time after the first Gamma Knife surgery (GKS) procedure was 6.6 months. Compared with patients with BC and NSCLC, patients with GIC had shorter OS and a higher incidence of SD. Compared with patients with NSCLC and GIC, patients with BC had significantly higher tumor reduction rates in both sessions. TP rates were similar among primary cancer types. There was no association of the tumor reduction rate with tumor control. The overall cumulative incidence of RN was 4.2%; further, the RN rates were similar among primary cancer types.
Two-stage SRS should be considered for BC and NSCLC if surgical resection is not indicated. For BMs from GIC, staged SRS should be carefully considered and adapted to each unique case given its lower tumor reduction rate and shorter OS.
立体定向放射外科（SRS）通常适用于因肿瘤过大（>10cm）而无法进行手术切除的脑转移瘤（BM）患者。分阶段 SRS 需要在放射治疗期间的每个阶段进行适应性计划，以提高肿瘤控制率并降低放射损伤。然而，目前还没有关于这种方法的肿瘤缩小率的研究。我们评估了多原发癌型分两阶段 SRS 的治疗效果。
我们分析了 178 例 182 例初始接受两阶段 SRS 治疗的大 BM 患者。主要癌症包括乳腺癌（BC）、非小细胞肺癌（NSCLC）和胃肠道癌（GIC）。我们分析了总生存期（OS）、神经死亡、全身死亡（SD）、肿瘤进展（TP）、肿瘤复发（TR）、放射性坏死（RN）以及两个阶段的肿瘤缩小率。
第一次伽玛刀手术后的中位生存时间为 6.6 个月。与 BC 和 NSCLC 患者相比，GIC 患者的 OS 更短，SD 发生率更高。与 NSCLC 和 GIC 患者相比，BC 患者在两个阶段的肿瘤缩小率均显著更高。不同原发癌型的 TP 率相似。肿瘤缩小率与肿瘤控制无相关性。总的累积 RN 发生率为 4.2%；此外，不同原发癌型的 RN 率相似。
如果不能进行手术切除，应考虑对 BC 和 NSCLC 患者采用两阶段 SRS。对于 GIC 引起的 BM，应根据每个病例的特点仔细考虑并调整分阶段 SRS，因为其肿瘤缩小率较低，OS 较短。
