Le Péchoux Cécile, Al Mohkles Hweej, Dhermain Frédéric
Institut Gustave-Roussy, département de radiothérapie, 114, rue Édouard-Vaillant, 94805 Villejuif, France.
Bull Cancer. 2013 Jan 1;100(1):35-43. doi: 10.1684/bdc.2012.1678.
Prophylactic cranial irradiation (PCI) plays a role in the management of lung cancer patients, especially small cell lung cancer (SCLC) patients. As multimodality treatments are now able to ensure better local control and a lower rate of extracranial metastases, brain relapse has become a major concern in lung cancer. As survival is poor after development of brain metastases (BM) in spite of specific treatment, PCI has been introduced in the 1970's. PCI has been evaluated in randomized trials in both SCLC and non-small cell lung cancer (NSCLC) to reduce the incidence of BM 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 25 Gy 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 BM related to NSCLC, but most BM will eventually recur so that PCI should be reconsidered. Few randomized trials have been performed. Most of them could demonstrate a decreased incidence of BM in patients with PCI, but they were not able to show an effect on survival as they were underpowered. New trials are needed. Among long-term survivors, neuro-cognitive toxicity may be observed. Several approaches are being evaluated to reduce this possible toxicity. PCI has no place for other solid tumours at risk such as HER2+ breast cancer patients.
预防性颅脑照射（PCI）在肺癌患者，尤其是小细胞肺癌（SCLC）患者的治疗中发挥着作用。由于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一个主要问题。尽管有针对性的治疗，但脑转移（BM）发生后的生存率仍然很低，因此PCI在20世纪70年代被引入。PCI已在SCLC和非小细胞肺癌（NSCLC）的随机试验中进行评估，以降低BM的发生率并可能提高生存率。PCI可显著降低局限期（LD）和广泛期（ED）SCLC以及非转移性NSCLC的BM发生率。对于SCLC，PCI可显著提高对一线治疗有反应的患者的LD（3年时从15%提高到20%）和ED（1年时从13%提高到27%）的总生存率；因此，它应成为所有ED反应者和LD良好反应者标准治疗的一部分。在LD SCLC患者中未证明PCI的剂量效应关系，因此推荐剂量为25 Gy，分10次给予。在NSCLC中，即使脑转移的风险低于SCLC，但它已成为一个具有挑战性的问题。研究已经确定了脑功能衰竭风险较高的亚组。与NSCLC相关的BM有更多的局部治疗可能性，但大多数BM最终仍会复发，因此应重新考虑PCI。很少有随机试验。其中大多数试验可以证明PCI患者的BM发生率降低，但由于样本量不足，它们无法显示对生存率的影响。需要进行新的试验。在长期幸存者中，可能会观察到神经认知毒性。正在评估几种方法来降低这种可能的毒性。PCI不适用于其他有风险的实体瘤，如HER2+乳腺癌患者。
