Pretreatment Anemia Portends Poor Survival and Nonlocal Disease Progression in Patients with Stage I Non-Small Cell Lung Cancer Treated with Stereotactic Body Radiation Therapy

IntroductionWe determined whether pretreatment anemia predicted for poor outcomes in the setting of early-stage NSCLC treated with stereotactic body radiation therapy (SBRT).MethodsPretreatment hemoglobin levels were evaluated to determine the association with local, regional, and distant control; disease-free survival; and overall survival. Survival rates were estimated with Kaplan-Meier analysis, and multivariate analysis was completed with adjustment for age, T stage, and radiation dose using the Cox proportional hazards model. Receiver operating characteristic curve analysis was used to determine the optimal pretreatment hemoglobin level that would predict for poor outcomes.ResultsA total of 147 cases of cases of early-stage NSCLC treated with SBRT were evaluated with a median follow-up of 28.9 months. The 3-year local, regional and distant control rates were 95%, 87%, and 89%, respectively. The 3-year overall survival and disease-free survival rates were 75% and 83%, respectively. On multivariate analysis, a lower pretreatment hemoglobin level predicted for poor regional control, poor disease-free survival, and overall survival (p = 0.02, p = 0.03, p = 0.05, respectively). Pretreatment hemoglobin levels did not predict poor local control. Receiver operating characteristic (ROC) analysis found that pretreatment hemoglobin values less than 12.2 g/dL optimally predicted for poor disease-free survival and regional control. The 3-year disease-free survival for patients with a hemoglobin level of at least 12.2 g/dL was 94% versus 70% in patients with a hemoglobin level less than 12.2 g/dL (p = 0.008).ConclusionsIn the setting of SBRT for early-stage NSCLC, we found pretreatment anemia to be predictive of aggressive disease with poor overall survival and nonlocal disease progression.