Preoperative Splenic area as a Prognostic Biomarker of Early-stage Non- small Cell Lung Cancer

Background: The correlation between the preoperative splenic area measured on CT scans and the overall survival (OS) of early-stage non-small cell lung cancer (NSCLC) patients is remains unclear. Methods A retrospective discovery cohort and validation cohort were created, consisting of consecutive NSCLC patients who underwent resection and preoperative CT scans. The patients were divided into two groups based on the measurement of their preoperative splenic area : normal and abnormal. The Cox proportional hazard model was used to analyze the correlation between splenic area and OS. Results The discovery and validation cohorts included 2532 patients (1374 (54.27%) males; the median (IQR) age was 59 (52–66) years), and 608 patients (403 (66.28%) males; age was 69 (62–76) years), respectively. Patients with the normal splenic area had 6% higher 5-year OS (n = 727 (80%)) than that patients with the abnormal splenic area (n = 1805 (74%)) (p = 0.007) in the discovery cohort. A similar result was obtained in the validation cohort. In univariable analysis, the OS hazard ratio (HR) for the patients with abnormal splenic area were 1.32 (95% confidence interval (CI): 1.08, 1.61) in the discovery cohort, and 1.59 (95% CI: 1.01, 2.50) in the validation cohort, respectively. Multivariable analysis demonstrated that abnormal splenic area was independent of shorter OS in the discovery (HR: 1.32, 95%CI: 1.08, 1.63) and validation cohorts (HR: 1.84, 95%CI: 1.12, 3.02). Conclusion Preoperative measurement of splenic area on CT scans can indicate poor prognosis in early-stage NSCLC patients.