Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
Cancer. 2011 Nov 1;117(21):4977-82. doi: 10.1002/cncr.26148. Epub 2011 Apr 14.
Previously irradiated recurrent medulloblastoma (MB) is a highly lethal disease. Reirradiation is often not considered secondary to its potential toxicity and uncertain efficacy. Analysis of retreatment could help identify the feasibility and role of reirradiation for recurrent MB.
Thirteen patients who underwent at least 1 course of reirradiation at the authors' institution as a component of management after recurrence were identified, and their medical records were analyzed.
At first diagnosis, all patients underwent surgical resection and radiation, with 69% of patients receiving chemotherapy. Median time to initial failure was 50 months (range, 14-103 months). Reirradiation subsite breakdown was as follows: posterior fossa, 46%; supratentorial/whole brain, 31%; spine, 23%; craniospinal, 8%. Median cumulative dose was 84 grays (range, 65-98.4 grays). Of 11 patients completing a full course of reirradiation, there were 6 failures, with 3 in the reirradiation field. Kaplan-Meier estimates of progression-free and overall survival since time of first recurrence were 48% and 65%, respectively at 5 years. Of patients without gross disease at reirradiation, 83% were without evidence of disease at last follow-up. With a median follow-up of 30 months, reirradiation was well tolerated, with only 1 case of asymptomatic, in-field radiation necrosis.
The results in this series are promising, but must be interpreted with caution given the limitations. Reirradiation provided most benefit to patients with no evidence of disease after surgical re-resection, and least to patients with gross disease. Important considerations for reirradiation toxicity development include duration between radiation courses and patient age. Further study of reirradiation as part of trimodality therapy is warranted.
先前接受过放疗的复发性髓母细胞瘤（MB）是一种高度致命的疾病。由于其潜在的毒性和不确定的疗效，再放疗通常不被考虑。对再治疗的分析可以帮助确定复发性 MB 再放疗的可行性和作用。
作者机构对至少接受过 1 次再放疗作为复发后治疗的 13 例患者进行了识别，并对其病历进行了分析。
在首次诊断时，所有患者均接受了手术切除和放疗，其中 69%的患者接受了化疗。首次失败的中位时间为 50 个月（范围，14-103 个月）。再放疗亚部位的分布如下：后颅窝，46%；幕上/全脑，31%；脊柱，23%；颅脊髓，8%。中位累积剂量为 84 戈瑞（范围，65-98.4 戈瑞）。在完成全疗程再放疗的 11 例患者中，有 6 例复发，其中 3 例在再放疗野内。首次复发后无进展生存和总生存的 Kaplan-Meier 估计分别为 5 年时的 48%和 65%。在再放疗时无大体疾病的患者中，83%的患者在最后一次随访时无疾病证据。在中位随访 30 个月时，再放疗耐受性良好，仅有 1 例无症状、局部放射性坏死。
尽管存在局限性，但本系列结果令人鼓舞。再放疗对手术后无疾病证据的患者最有益，对大体疾病患者益处最小。再放疗毒性发展的重要考虑因素包括放疗次数之间的时间间隔和患者年龄。需要进一步研究再放疗作为三联疗法的一部分。
