Presentation and outcomes of KRAS mutant non-small cell lung cancer patients with stage IV disease at diagnosis (de novo) versus at recurrence.

Close monitoring after diagnosis of patients with stage I-III non-small cell lung cancer (NSCLC) may result in fitter patients with lower disease burden at the time of metastatic recurrence or progression compared to patients diagnosed initially as stage IV (de novo). We compared the presentation, treatments, and outcomes of patients with KRAS-mutated NSCLC with de novo versus recurrent stage IV disease. Of 109 patients, 94% had a smoking history. When compared to patients with KRAS-mutated NSCLC who developed stage IV disease at recurrence (n = 38), de novo stage IV patients (n = 71) had worse ECOG performance status (p = 0.007), greater numbers of extra-thoracic metastatic sites (p = 0.001), and were less likely to receive 2nd/3rd line systemic therapy (p = 0.05, p = 0.002) or targeted therapy (p = 0.001). De novo metastatic patients had shorter overall survival than metastatic patients at recurrence (9.1 versus 24.2 months; adjusted-hazard-ratio=1.94 (95% CI: 1.14-3.28; p = 0.01)). There is a critical need for well-tolerated targeted therapies in the first-line setting for metastatic patients with de novo, high-burden, stage IV KRAS-mutated NSCLCs.