Prophylactic cranial irradiation confers favourable prognosis for patients with limited‐stage small cell lung cancer in the era of MRI: A propensity score‐matched analysis

Abstract

Introduction: Prophylactic cranial irradiation (PCI) is recommended for patients with limited-stage small cell lung cancer (LS-SCLC) who achieve good response after chemoradiotherapy. But PCI is neurotoxic. Magnetic resonance imaging (MRI) is the standard tool for evaluating brain metastasis (BM). This study was to retrospectively analyse the necessity of PCI in the era of MRI in LS-SCLC. Methods: From July 2013 to June 2017, 190 patients with LS-SCLC who were treated with definitive chemoradiotherapy were included and analysed in this study. They were divided into the PCI group and non-PCI group. Propensity score matching (PSM) analysis was used to balance the variable differences. The Kaplan-Meier method was applied to estimate survival with log-rank test to ascertain significance between different groups. Results: Seventy-seven patients (40.5%) received PCI after chemoradiotherapy. After adjustment for propensity scores, 69 pairs of patients were matched between two groups. After PSM, the 1-year and 3-year OS rates were 96.9% and 48.5% in PCI group versus 89.9% and 25.0% in non-PCI group (HR: 0.419, 95% CI: 0.251-0.701, P = 0.001). The 1-year and 3-year BMFS in PCI group were 96.8% and 67.5% versus 62.3% and 37.9% in non-PCI group (HR: 0.247, 95% CI: 0.132-0.460, P < 0.001). Conclusion:For patients showing no BM on MRI after definitive CRT, PCI confers less BM and better OS in LS-SCLC.

Prophylactic cranial irradiation effect on survival in patients with small cell lung cancer: a comprehensive systematic review and meta-analysis

“…Furthermore, in studies that used pre-PCI brain MRI in LS-SCLC patients, PCI improved both OS and PFS. These results are in line with some previous studies [34][35][36] suggesting that more accurate identification of patients who attained complete response and exclusion of patients with occult BMs leads to the selection of patients who are more responsive to PCI. Prospective clinical trials (including NCT04829708, NCT04790253, NCT05651802, and NCT04155034; ClinicalTrials.gov) could further elaborate on these findings.…”