Institute for Cancer Research in People's Liberation Army, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China.
Jpn J Clin Oncol. 2012 Sep;42(9):856-60. doi: 10.1093/jjco/hys091. Epub 2012 Jun 13.
The recurrence and progression of brain metastases after brain irradiation are a major cause of mortality and morbidity in patients with cancer. The risk of radiation-induced neurotoxicity and efficacy probably leads oncologists to not consider re-irradiation. We report the case of a 48-year-old Asian male diagnosed with squamous cell lung cancer and multiple brain metastases initially treated with 40 Gy whole-brain radiotherapy and 20 Gy partial brain boost. Fourteen gray stereotactic radiosurgery as salvage for brain metastases in the left occipital lobe was performed after initial irradiation. The recurrence of brain metastases in the left occipital lobe was demonstrated on magnetic resonance imaging at 9 months after initial radiotherapy. He received the second course of 28 Gy stereotactic radiosurgery for the recurrent brain metastases in the left occipital lobe. The third relapse of brain metastases was demonstrated by a magnetic resonance imaging scan at 7 months after the second radiotherapy. The third course of irradiation was performed because he refused to undergo surgical resection of the recurrent brain metastases. The third course of irradiation used a pulsed reduced dose-rate radiotherapy technique. It was delivered in a series of 0.2 Gy pulses separated by 3-min intervals. The recurrent brain metastases were treated with a dose of 60 Gy using 30 daily fractions of 2 Gy. Despite the brain metastases receiving 162 Gy irradiation, this patient had no apparent acute or late neurologic toxicities and showed clinical improvement. This is the first report of the pulsed reduced dose-rate radiotherapy technique being used as the third course of radiotherapy for recurrent brain metastases.
脑部放疗后脑转移的复发和进展是癌症患者死亡和发病的主要原因。放射性神经毒性和疗效的风险可能导致肿瘤学家不考虑再放疗。我们报告了一例 48 岁亚洲男性，诊断为鳞状细胞肺癌和多发脑转移，最初接受了 40 Gy 全脑放疗和 20 Gy 局部脑增强放疗。初次照射后，14 个格雷立体定向放射外科手术用于挽救左枕叶的脑转移。初次放疗后 9 个月，磁共振成像显示左枕叶脑转移复发。他接受了第二疗程 28 Gy 立体定向放射外科手术治疗左枕叶复发性脑转移。第二次放疗后 7 个月，磁共振成像显示第三次脑转移复发。由于他拒绝接受复发性脑转移的手术切除，因此进行了第三次放疗。第三次放疗采用脉冲降剂量率放疗技术。它以 0.2 Gy 的脉冲序列进行，间隔 3 分钟。采用 30 次 2 Gy 的每日分割，对复发性脑转移灶给予 60 Gy 的剂量。尽管脑转移灶接受了 162 Gy 的照射，但该患者没有明显的急性或迟发性神经毒性，并显示出临床改善。这是首例报告使用脉冲降剂量率放疗技术作为复发性脑转移的第三次放疗。
