Prognosis and risk factors of brain metastases from limited-stage small cell lung cancer after complete resection / 中华放射肿瘤学杂志

ABSTRACT

Objective:To analyze the prognosis and risk factors for brain metastases (BM) in patients with limited-stage small cell lung cancer (LS-SCLC) after complete resection, aiming to identify those most likely to benefit from prophylactic cranial irradiation (PCI).Methods:Clinical data of 94 patients with LS-SCLC treated in Cangzhou Integrated Traditional Chinese and Western Medicine Hospital from January 2005 to December 2018 who underwent complete resection were retrospectively analyzed, including 31 cases treated with PCI and 63 without PCI. Prognostic factors and risk factors of BM were analyzed by Kaplan-Meier method. The differences between two groups were analyzed by log-rank test. Independent risk factors of overall survival (OS) and BM were assessed by multivariate Cox regression model.Results:The 2-year and 5-year OS rates were 80.6% and 61.3% in the PCI group, and 61.9% and 46.0% in the non-PCI group, respectively ( P=0.001). The 2-year and 5-year brain metastasis-free survival (BMFS) rates were 80.6% and 54.8% in the PCI group, and 57.1% and 42.9% in the non-PCI group, respectively ( P=0.045). The 2-year and 5-year progression-free survival (PFS) rates were 71.0% and 48.4% in the PCI group, and 49.2% and 34.9% in the non-PCI group, respectively ( P=0.016). PCI could improve OS in patients with pII/III stage LS-SCLC ( P=0.039, P=0.013), but the OS benefit in patients with pI stage LS-SCLC was not significant ( P=0.167). BM occurred in 3 patients (9.7%) in the PCI group, which was significantly lower than that in the non-PCI group ( n=17, 27.0%; P=0.044); there was no significant difference in the BM rate of patients with pI and pII stage LS-SCLC between PCI and non-PCI groups ( P=0.285, P=0.468); and the BM rate of patients with pIII stage LS-SCLC in the PCI group was significantly lower than that in the non-PCI group ( P=0.041). Multivariate analysis showed age ≥60 ( HR=2.803, P=0.001), BM ( HR=2.239, P=0.022), no PCI ( HR=0.341, P=0.004) and pathological stage pII/III ( HR=4.963, P=0.002) were the independent high-risk factors affecting OS; and pathological stage pII/III ( HR=11.665, P=0.007) was an independent high-risk factor affecting BM. Conclusions:LS-SCLC patients with pII-III stage have a higher risk of developing BM and poor prognosis after complete resection, and should receive PCI treatment. However, LS-SCLC patients with pI stage may not benefit significantly.