Fisher Barbara, Seiferheld Wendy, Schultz Christopher, DeAngelis Lisa, Nelson Diane, Schold S C, Curran W, Mehta M
Department of Radiation Oncology, London Regional Cancer Program and University of Western Ontario, 790 Commissioners Road East, London N6A 4L6, Ontario, Canada.
J Neurooncol. 2005 Sep;74(2):201-5. doi: 10.1007/s11060-004-6596-9.
To determine whether a lower dose of hyperfractionated whole brain radiation reduces central nervous system morbidity without compromising survival for primary CNS lymphoma (PCNSL) patients receiving combined modality treatment.
One hundred and two patients received a course of pre-radiation chemotherapy, followed by whole brain radiation, followed by cytosine-arabinoside. Initial radiation dose was 45 Gy/25 fractions (RT) then the study was amended to reduce this dose for complete responders to induction chemotherapy to 36 Gy/30 fractions/3 weeks (HFX). Eighty-two patients received radiotherapy and were evaluable for toxicity analysis (66 RT patients and 16 HFX patients). MMSE scores and survival for the 40 patients who received radiotherapy after complete response to chemotherapy (27 RT and 13 HFX) were compared. There were no notable differences in pre-treatment patient characteristics between the RT and HFX groups.
Neurotoxicity: By 4 years, there were 8/82 (10%) grade 5 neurotoxicities which included 2/16 (13%) grade 5 encephalopathies and 0/27 in the RT group of complete responders to chemotherapy. Survival: There was no statistically significant difference in overall or progression-free survival (PFS) between the chemotherapy-complete responders who received RT and HFX. Cognitive function testing: MMSE scores improved at 8 months across both treatment groups. Analysis of the area under the MMSE curve at 8 months showed no statistically significant difference between RT and HFX groups (P=0.81). Leukoencephalopathy occurred later in the HFX group than in the RT patients.
Although the HFX schedule represented a 25% reduction in biologically effective tumor dose in comparison, PFS and overall survival were not significantly affected. The HFX regimen delayed but did not eliminate severe neurotoxicity from chemoradiation in PCNSL patients.
确定对于接受综合治疗的原发性中枢神经系统淋巴瘤（PCNSL）患者，较低剂量的超分割全脑放疗在不影响生存的情况下是否能降低中枢神经系统的发病率。
102例患者接受了一个疗程的放疗前化疗，随后进行全脑放疗，再给予阿糖胞苷。初始放疗剂量为45 Gy/25次分割（RT），之后研究进行了修正，将诱导化疗完全缓解者的剂量降至36 Gy/30次分割/3周（HFX）。82例患者接受了放疗并可进行毒性分析（66例RT患者和16例HFX患者）。比较了40例化疗完全缓解后接受放疗的患者（27例RT和13例HFX）的简易精神状态检查表（MMSE）评分和生存率。RT组和HFX组治疗前患者特征无显著差异。
神经毒性：到4年时，有8/82（10%）例5级神经毒性反应，其中包括2/16（13%）例5级脑病，化疗完全缓解的RT组中为0/27例。生存率：接受RT和HFX的化疗完全缓解者的总生存期或无进展生存期（PFS）无统计学显著差异。认知功能测试：两个治疗组在8个月时MMSE评分均有所改善。8个月时MMSE曲线下面积分析显示RT组和HFX组之间无统计学显著差异（P = 0.81）。白质脑病在HFX组比RT患者出现得晚。
尽管与RT相比，HFX方案使生物等效肿瘤剂量降低了25%，但PFS和总生存期未受到显著影响。HFX方案延迟但未消除PCNSL患者放化疗所致的严重神经毒性。
