The effect of prophylactic cranial irradiation (PCI) for young stage III NSCLC patients: Subgroup analyses of the NVALT-11/DLCRG-02 study

Background: The NVALT-11/DLCRG-02 phase III study compared PCI to observation after chemo-radiotherapy (RT) for stage III NSCLC and showed a significant decrease in the cumulative incidence of symptomatic brain metastases (BM) in the PCI arm at two years (7% vs 27% [HR 0.23]). We here performed exploratory subgroup analyses. Methods: Two year cumulative incidence rates were calculated and competing risk regression, with death of any cause as competing risk, was used to examine the time to symptomatic BM in the following subgr