Department of Radiation Oncology, Weill Cornell Medical College, New York, NY; Savera Liberty Medical, New York.
Faculty of Medicine, Bruce Rappaport Technion, Haifa, Israel.
Brachytherapy. 2020 Sep-Oct;19(5):705-712. doi: 10.1016/j.brachy.2020.06.013.
Re-irradiation of recurrent glioblastoma (GBM) may delay further recurrence but re-irradiation increases the risk of radionecrosis (RN). Salvage therapy should focus on balancing local control (LC) and toxicity. We report the results of using intraoperative Cesium-131 (Cs-131) brachytherapy for recurrent GBM in a population of patients who also received bevacizumab.
Twenty patients with recurrent GBM underwent maximally safe neurosurgical resection with Cs-131 brachytherapy between 2010 and 2015. Eighty Gy was prescribed to 0.5 cm from the surface of the resection cavity. All patients previously received adjuvant radiotherapy and temozolomide, and received bevacizumab before or after salvage brachytherapy. Seven of 20 (35%) tumors were multiply recurrent and had been previously salvaged with external beam radiotherapy. Patients received MRI scans every 2 months monitored for recurrence, progression, and RN.
Median tumor diameter was 4.65 cm (range, 1.2-6.3 cm). Median number of seeds pace was 41 (range, 20-74) with total seed activity 96.8U (range, 41.08-201.3U). At a median followup of 19 months, crude LC was 85% and median overall survival was 9 months (range, 5-26 months). There were two postoperative wound infections (10%), three seizures (15%), and 0% incidence of RN.
Our study demonstrates that while LC and survival are similar to other studies of postoperative external beam radiotherapy, no RN occurred in any of these patients, including 7 multiply re-irradiated patients. Of interest, there were patients with multiple recurrences whose survival extended beyond 20 months. These findings suggest that the use of highly conformal Cs-131 brachytherapy is a promising treatment for patients with recurrent GBM with minimal risk of development of RN.
复发性胶质母细胞瘤（GBM）的再放疗可能会延迟进一步复发，但会增加放射性坏死（RN）的风险。挽救性治疗应侧重于平衡局部控制（LC）和毒性。我们报告了在接受贝伐单抗治疗的患者人群中，使用术中铯-131（Cs-131）近距离放疗治疗复发性 GBM 的结果。
2010 年至 2015 年间，20 例复发性 GBM 患者接受了最大限度安全的神经外科切除和 Cs-131 近距离放疗。80Gy 被规定用于距切除腔表面 0.5cm 处。所有患者之前都接受了辅助放疗和替莫唑胺治疗，并在挽救性近距离放疗前或后接受了贝伐单抗治疗。20 例（35%）肿瘤中有 7 例为多发性复发性肿瘤，并已接受过外照射放疗挽救治疗。患者每 2 个月接受一次 MRI 扫描，以监测复发、进展和 RN。
肿瘤直径中位数为 4.65cm（范围，1.2-6.3cm）。种子中位数为 41 个（范围，20-74 个），总种子活度为 96.8U（范围，41.08-201.3U）。在中位随访 19 个月时，粗局部控制率为 85%，中位总生存期为 9 个月（范围，5-26 个月）。有 2 例术后伤口感染（10%）、3 例癫痫发作（15%）和 0%的放射性坏死发生率。
我们的研究表明，虽然 LC 和生存率与其他术后外照射放疗研究相似，但在这些患者中没有发生放射性坏死，包括 7 例多次再放疗的患者。有趣的是，有一些多次复发的患者，其生存时间超过了 20 个月。这些发现表明，使用高度适形的 Cs-131 近距离放疗是治疗复发性 GBM 的一种有前途的方法，其放射性坏死的风险最小。
