A Nomogram for Predicting Cancer‐Specific Survival in Young Patients With Advanced Lung Cancer Based on Competing Risk Model

ABSTRACT Background Young lung cancer is a rare subgroup accounting for 5% of lung cancer. The aim of this study was to compare the causes of death (COD) among lung cancer patients of different age groups and construct a nomogram to predict cancer‐specific survival (CSS) in young patients with advanced stage. Methods Lung cancer patients diagnosed between 2004 and 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database and stratified into the young (18–45 years) and old (> 45 years) groups to compare their COD. Young patients diagnosed with advanced stage (IVa and IVb) from 2010 to 2015 were reselected and divided into training and validation cohorts (7:3). Independent prognostic factors were identified through the Fine‐Gray's test and further integrated to the competing risk model. The area under the receiver operating characteristic curve (AUC), consistency index (C‐index), and calibration curve were applied for validation. Results The proportion of cancer‐specific death (CSD) in young patients was higher than that in old patients with early‐stage lung cancer (p