Age, gender, performance status and stage outperformed stage alone in predicting overall survival (OS) in patients with small cell lung cancer: A pooled analysis of 1,623 patients from the North Central Cancer Treatment Group

Abstract

7723 Background: It is critical that we understand the impact of patient, tumor, and treatment-related factors on patient prognosis for the proper design and analysis of Small Cell Lung Cancer (SCLC) trials. An analysis of 15 SCLC trials was performed to investigate and improve our understanding of several factors on OS. Methods: Data from 1623 patients (pts) were used. Age, gender, performance status (PS), tumor stage, body mass index (BMI), creatinine levels, hemoglobin levels, white blood cell counts (WBC), platelet counts, and bilirubin levels were tested for prognostic significance for OS both univariately and multivariately using a Cox Proportional Hazards Model. Models were stratified by protocol, and analyses carried out on the complete data available based on the selected covariates. Model discrimination (i.e., ability to discriminate patients with different survival times) was evaluated using the concordance index (COI). Results: Median follow-up was 63.1 months (range: 1.9 to 155.7). 58% and 42% of pts had extensive-stage or limited-stage SCLC, respectively. Patients with extensive-stage disease, PS>0, increased age, and male gender had significantly worse OS both univariately and multivariately. Patients with increased WBC had significantly worse OS univariately, however, WBC was not a significant predictor when adjusted for other factors. None of the other factors were prognostic for OS. Model discrimination improved by 6.3% when age, gender, PS, and stage were included in a model compared to a model with stage alone (COI improved from 0.63 to 0.67). Conclusions: Age, gender, PS and stage did better at predicting OS than stage alone. Further refinement of this model, including the addition of number of metastatic sites at baseline and treatment related factors, is currently underway. No significant financial relationships to disclose. [Table: see text]