Systematic review and meta-analysis of prophylactic cranial irradiation in small cell lung cancer

Patients with small cell lung cancer (SCLC) are at high risk for brain metastases. Prophylactic cranial irradiation (PCI) is recommended in this population to reduce the incidence of brain metastases and prolong survival. Systematic review and meta-analysis of studies reporting on the use of PCI in SCLC patients found that PCI was associated with longer survival in all patients (HR 0.59; p<0.001; n=56.770), in patients with limited stage disease (HR 0.60; p<0.001; 78 studies with 27.137 patients), and in patients with extensive stage disease (HR 0.59; p<0.001; 28 studies with 26.467 patients). In a subgroup analysis on studies that used MRI to exclude presence of brain metastases before PCI, overall survival did not differ significantly between patients who did or did not receive PCI (HR.074; p=0.08; 9 studies with 1384 patients). The authors conclude that administration of PCI was associated with a survival benefit, but not when considering studies that radiographically confirmed absence of brain metastases, suggesting that the survival benefit conferred by PCI might be therapeutic rather than prophylactic.