Conditional Survival of Surgically Treated Patients with Lung Cancer: A Comprehensive Analyses of Overall, Recurrence-Free, and Relative Survival

PURPOSE: Survival probability changes over time in cancer survivors. This study examined conditional survival in patients undergoing curative resection for non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Five-year conditional recurrence-free survival (CRFS), conditional overall survival (COS), and conditional relative survival (CRS) up to 10 years after surgery were calculated in patients who underwent NSCLC resection from 1994 to 2016. These rates were stratified according to age, sex, year of diagnosis, pathological stage, tumor histology, smoking status, comorbidity, and lung function. RESULTS: Five-year CRFS increased from 65.6% at baseline to 90.9% at 10 years after surgery. Early differences in 5-year CRFS according to stratified patient characteristics disappeared, except for age: older patients exhibited persistently lower 5-year CRFS. Five-year COS increased from 72.7% to 78.3% at 8 years and then decreased to 75.4% at 10 years. Five-year CRS increased from 79.0% at baseline to 86.8% at 10 years. Older age and higher pathologic stage were associated with lower 5-year COS and CRS up to 10 years after surgery. Female patients, those with adenocarcinoma histology, non-smokers, patient without comorbidities and had good lung function showed higher COS and CRS. CONCLUSION: CRFS improved over time, but significant risk remained after 5 years. CRS slightly improved over time but did not reach 90%, suggesting significant excess mortality compared to the general population. Age and stage remained significant predictors of conditional survival several years after surgery. Our conditional survival estimates should help clinicians and patients make informed treatment and personal life decisions based on survivorship status.