The effect of comorbidity on stage-specific survival in resected non-small cell lung cancer patients

Abstract

Aim: To quantify the effect of comorbidity on stage-specific survival in resected non-small cell lung cancer (NSCLC) patients.

Methods: From the Danish Lung Cancer Registry, 20,461 patients diagnosed with lung cancer between 1st January 2005 and 31st December 2010 were identified. Among 3152 NSCLC patients who underwent surgical resection, mortality hazard ratios were calculated during three consecutive time periods following surgery (0-1 month, 1 month-1 year and >1 year) according to Charlson comorbidity score (CCS 0, 1, 2, 3+), Eastern Cooperative Oncology Group (ECOG) performance status, lung function, age, sex, pathological T (pT) and N (pN) stage using Cox proportional hazard modelling. The Kaplan Meier method was used to describe stage-specific survival according to the CCS.

Results: Severe comorbidity (CCS 3+) was independently associated with significantly higher death rates throughout the three periods of follow-up [Hazard ratio (HR) 2.06 (1.13-3.75) for CCS 3+ in 0-1 month, 1.57 (1.17-2.12) 3+ during1 month-1 year and 1.84 (1.42-2.37) after 1 year]. Stage-specific 5-year survival in patients with severe comorbidity was significantly lower than in patients without comorbid disease [e.g. 38% (95% confidence interval (CI) 23-53%) for pT1 and CCS 3+ versus 69% (62-75%) for pT1 and CCS 0].

Conclusion: Severe comorbidity affects survival of NSCLC patients who undergo surgical resection by as much as a single stage increment and this effect persists throughout follow-up. Further research may be necessary to help identify which patients are most likely to benefit from surgery.