Department of Neurosurgery, Kyung Hee University College of Medicine, Seoul, Korea.
Department of Neurosurgery, Ulsan University Hospital, University of Ulsan, College of Medicine, Ulsan, Korea.
World Neurosurg. 2019 Dec;132:e399-e402. doi: 10.1016/j.wneu.2019.08.136. Epub 2019 Aug 30.
The effectiveness of tumor control after Gamma Knife radiosurgery (GKS) for intracranial meningioma is well established. Moreover, GKS is an alternative to reduce surgical-remnant meningioma recurrence. Nevertheless, the tumor can recur even after GKS and is associated with its histologic malignancy. We here investigated the risk factors associated with recurrence from remnant lesions after GKS, assessing recurrence patterns according to histological grades.
From January 2007 to January 2017, 218 patients underwent GKS for surgical-remnant lesions. To evaluate post-GKS lesion recurrence, pre-GKS magnetic resonance images were compared with those at follow-up. We retrospectively analyzed the histologic classification of meningioma and patients' clinical characteristics (sex, age, tumor location, target volume, and prescription dose).
Of the 218 patients, 13 (5.9%) developed post-GKS recurrence within a mean follow-up period of 37.4 months. The recurrence patterns were as follows: adjacent to the 50% marginal-dose field (9 patients); within the 50% marginal-dose field (2 patients); and outside the field (2 patients). Six of 196 World Health Organization grade I meningioma cases, 6 of 20 grade II cases, and 1 of 2 grade III cases developed recurrence. Thus 32% of high-grade meningioma cases (grades II and III) developed recurrence during the follow-up period. Histologic grade was significantly associated (P < 0.001) with recurrence.
The study findings indicate that the post-GKS meningioma recurrence likelihood is high when the meningioma has malignant histologic features. In addition, considering the recurrence patterns, it is important to define a precise target for GKS.
伽玛刀放射外科（GKS）治疗颅内脑膜瘤的肿瘤控制效果已得到充分证实。此外，GKS 是降低手术残留脑膜瘤复发的一种选择。然而，即使在 GKS 后肿瘤仍可能复发，并与组织学恶性程度相关。我们在此研究了与 GKS 后残留病变复发相关的危险因素，并根据组织学分级评估了复发模式。
2007 年 1 月至 2017 年 1 月，218 例患者因手术残留病灶接受 GKS 治疗。为了评估 GKS 后病变的复发情况，将术前磁共振图像与随访时的图像进行比较。我们回顾性分析了脑膜瘤的组织学分类和患者的临床特征（性别、年龄、肿瘤位置、靶体积和处方剂量）。
在 218 例患者中，13 例（5.9%）在平均 37.4 个月的随访期间发生 GKS 后复发。复发模式如下：毗邻 50%边缘剂量场（9 例）；位于 50%边缘剂量场（2 例）；和场外（2 例）。196 例世界卫生组织 I 级脑膜瘤中有 6 例、20 例 II 级中有 6 例、2 例 III 级中有 1 例发生复发。因此，在随访期间，32%的高级别脑膜瘤（II 级和 III 级）发生了复发。组织学分级与复发显著相关（P<0.001）。
研究结果表明，当脑膜瘤具有恶性组织学特征时，GKS 后脑膜瘤复发的可能性较高。此外，考虑到复发模式，为 GKS 精确定义靶区很重要。
