The Role of Prophylactic Cranial Irradiation in Patients With Extensive Stage Small Cell Lung Cancer: A Systematic Review and Meta-Analysis.

INTRODUCTION: The role of prophylactic cranial irradiation (PCI) is controversial in patients with extensive stage small cell lung cancer. The aim of this study was to determine the impact of PCI in these patients.

METHODS: We performed a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A systematic literature search was conducted in MEDLINE, EMBASE, and the Cochrane Central Register. The primary outcome was overall survival (OS).

RESULTS: We identified five studies comprising 984 patients, of whom 448 received PCI and 536 did not receive PCI. In pooled estimates, PCI did not statistically improve OS compared with controls (hazard ratio [HR] = 0.82; 95% confidence interval [CI]: 0.60-1.11; I2  = 77%; p = 0.19). However, the PCI group had a significant advantage in 1-year survival compared to the no-PCI group (37.1% versus 27.1%; risk ratio = 0.87; 95% CI: 0.80-0.95; I2  = 47%; p = 0.002), and the pooled estimates indicated that progression-free survival and the risk of brain metastasis were associated with significant benefit in the PCI group (HR = 0.83; 95% CI: 0.70-0.98; I2  = 22%; p = 0.03; and HR = 0.34; 95% CI: 0.23-0.50; I2  = 0%; p < 0.001, respectively).

CONCLUSIONS: Our findings suggest that PCI in patients with extensive stage small cell lung cancer may lead to a significant benefit in 1-year survival, progression-free survival, and the risk of brain metastasis, despite the lack of a significant advantage in OS.