Survival Implications of De Novo Versus Recurrent Metastatic Non-Small Cell Lung Cancer.

Objectives: Metastatic non-small cell lung cancer (NSCLC) has a poor prognosis. Most patients present with stage IV, and many patients treated curatively with stage I to III develop recurrent metastatic disease. It is unknown whether the natural history differs between patients with recurrent versus de novo metastatic NSCLC. We hypothesized that de novo metastatic status is associated with decreased overall survival compared with recurrent metastatic disease.

Materials and methods: A retrospective review was completed of all patients with NSCLC referred to BC Cancer from 2005 to 2012. Two cohorts were created; de novo metastatic disease and patients treated with curative intent (surgery or radiotherapy) that developed recurrent, metastatic disease. Information was collected on known prognostic and predictive factors. Overall survival was calculated from the date of diagnosis of metastatic disease.

Results: A total of 9651 patients were evaluated, 5782 (60%) with de novo stage IV disease, and 3869 (40%) with stage I to III disease. Of the 1658 patients who received curative therapy for stage I to III disease, 757 (46%) developed metastases. Patients in the de novo cohort versus recurrent cohort were more likely male (52% vs. 48%), have poorer performance status (Eastern Cooperative Oncology Group≥2 50% vs. 44%), and receive no palliative systemic therapy (67% vs. 61%). The median overall survival in the de novo cohort was 4.7 versus 6.9 m in the recurrent cohort (P<0.001). De novo status was associated with shorter overall survival and this remained significant in a multivariate model that incorporated known prognostic factors.

Conclusions: In a large population-based study of NSCLC, de novo metastatic status was independently associated with decreased overall survival from the time of metastatic disease diagnosis.