Farooqi Ahsan S, Holliday Emma B, Allen Pamela K, Wei Xiong, Cox James D, Komaki Ritsuko
Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States.
Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States.
Radiother Oncol. 2017 Feb;122(2):307-312. doi: 10.1016/j.radonc.2016.11.012. Epub 2017 Jan 7.
Prophylactic cranial irradiation (PCI) can improve overall survival (OS) and suppress brain metastases (BM) in patients with limited-stage small cell lung cancer (LS-SCLC) after complete response to primary therapy. However, PCI can be toxic. We sought to identify characteristics of patients who may not benefit from PCI.
We identified 658 patients who received chemoradiotherapy at MD Anderson in 1986-2012; 364 received PCI and 294 did not. Median follow-up time was 21.2months (range 1.2-240.8months). Cox proportional hazards regression, competing-risk regression, and Kaplan-Meier analyses were used to identify factors influencing OS and BM.
PCI reduced risks of death [HR 0.73, 95% CI 0.61-0.88, P=0.001] and BM [HR 0.54, 95% CI 0.39-0.76, P<0.001]. Having tumors ⩾5cm increased the risk of BM [HR 1.77, 95% CI 1.22-2.55, P=0.002] but not death [HR 1.16, 95% CI 0.96-1.40, P=0.114]. Among patients ⩾70years with ⩾5-cm tumors, PCI did not improve OS [2-year rates 39.4% vs 40.9%, P=0.739].
PCI remains standard therapy after complete response to chemoradiotherapy for LS-SCLC. However, older patients may be at risk from comorbidity or extracranial disease. Further work is warranted to identify patients who may not benefit from PCI.
预防性颅脑照射（PCI）可提高局限期小细胞肺癌（LS-SCLC）患者在对初始治疗完全缓解后的总生存期（OS）并抑制脑转移（BM）。然而，PCI可能具有毒性。我们试图确定可能无法从PCI中获益的患者特征。
我们确定了1986年至2012年在MD安德森癌症中心接受放化疗的658例患者；364例接受了PCI，294例未接受。中位随访时间为21.2个月（范围1.2至240.8个月）。采用Cox比例风险回归、竞争风险回归和Kaplan-Meier分析来确定影响OS和BM的因素。
PCI降低了死亡风险[风险比（HR）0.73，95%置信区间（CI）0.61 - 0.88，P = 0.001]和BM风险[HR 0.54，95% CI 0.39 - 0.76，P < 0.001]。肿瘤≥5 cm会增加BM风险[HR 1.77，95% CI 1.22 - 2.55，P = 0.002]，但不会增加死亡风险[HR 1.16，95% CI 0.96 - 1.40，P = 0.114]。在年龄≥70岁且肿瘤≥5 cm的患者中，PCI并未改善OS[2年生存率分别为39.4%和40.9%，P = 0.739]。
对于LS-SCLC患者，在放化疗完全缓解后，PCI仍然是标准治疗。然而，老年患者可能因合并症或颅外疾病而面临风险。有必要进一步开展工作以确定可能无法从PCI中获益的患者。
