Radiation Oncology Department, Gustave-Roussy Institute, Villejuif, France.
Cancer Treat Rev. 2011 Jun;37(4):261-5. doi: 10.1016/j.ctrv.2010.08.009. Epub 2010 Oct 8.
As multi-modality treatments are now able to ensure better local control and a lower rate of extra cranial metastases, brain relapse has become a major concern in lung cancer. As survival is poor after development of brain metastases in spite of specific treatment, prophylactic cranial irradiation (PCI) has been introduced in the 70's. PCI has been evaluated in randomized trials in both small-cell (SCLC) and non-small-cell (NSCLC) lung cancers to reduce the incidence of brain metastases and possibly increase survival. PCI reduces significantly the BM rate in both limited disease (LD) and extensive disease (ED) SCLC and in non-metastatic NSCLC. Considering SCLC, PCI significantly improves overall survival in LD (from 15% to 20% at 3 years) and ED (from 13% to 27% at 1 year) in patients who respond to first-line treatment; it should thus be part of the standard treatment in all responders in ED and in good responders in LD. No dose-effect relationship for PCI was demonstrated in LD SCLC patients so that the recommended dose is 25Gy in 10 fractions. In NSCLC, even if the risk of brain dissemination is lower than in SCLC, it has become a challenging issue. Studies have identified subgroups at higher risk of brain failure. There are more local treatment possibilities for NSCLC patients with BM, but most of them will eventually recur so that PCI should be reconsidered. Few randomized trials have been performed and they were not able to show an effect on survival as they were underpowered. New trials are needed.
随着多模式治疗现在能够确保更好的局部控制和更低的颅外转移率，脑转移已成为肺癌的主要关注点。尽管有特定的治疗方法，但脑转移后的生存仍然很差，因此预防性颅脑照射（PCI）在 70 年代被引入。PCI 已在小细胞肺癌（SCLC）和非小细胞肺癌（NSCLC）的随机试验中进行了评估，以降低脑转移的发生率并可能提高生存率。PCI 显著降低了局限性疾病（LD）和广泛性疾病（ED）SCLC 以及非转移性 NSCLC 患者的 BM 发生率。考虑到 SCLC，PCI 显著改善了对一线治疗有反应的 LD（3 年时从 15%增加到 20%）和 ED（1 年时从 13%增加到 27%）患者的总生存率；因此，它应该成为 ED 中所有有反应者和 LD 中反应良好者的标准治疗的一部分。在 LD SCLC 患者中未证明 PCI 存在剂量效应关系，因此推荐剂量为 25Gy，分 10 次。在 NSCLC 中，尽管脑播散的风险低于 SCLC，但它已成为一个具有挑战性的问题。研究已经确定了具有更高脑失败风险的亚组。对于有 BM 的 NSCLC 患者有更多的局部治疗选择，但他们中的大多数最终会复发，因此应重新考虑 PCI。已经进行了一些随机试验，但由于效力不足，未能显示对生存的影响。需要新的试验。
