Prophylactic cranial irradiation in resected small cell lung cancer: A systematic review with meta-analysis

Background: The use of PCI in early operable patients with small cell lung cancer (SCLC) is still controversial. Therefore, we conducted a systematic review with meta-analysis to investigate the effects of PCI in resected SCLC patients. Methods: Relevant studies were identified from PubMed and EMBASE databases, the pooled hazard risks were obtained by the random-effects model. We also analyzed the brain metastasis (BM) risk in p-stage I patients without PCI. Results: Five retrospective studies were identified and a total of 1691 patients were included in our analysis, 315 of them received PCI. For all the resected patients, PCI was associated with improved overall survival (HR: 0.52, 95% CI: 0.33-0.82), and reduced brain metastasis risk (RR: 0.50, 95%CI: 0.32-0.78). However, with regard to p-stage I patients, no survival benefit was brought by PCI (HR: 0.87, 95% CI: 0.34-2.24). Moreover, the pooled analysis of 7 studies found that the 5-year brain metastasis risk was relatively low (12%, 95% CI: 8%-17%) for p-stage I patients without PCI. Conclusions: PCI might be associated with a favorable survival advantage and reduced BM risk in complete resected SCLC patients, except for p-stage I patients.