Charlson Comorbidity Index as a Predictor of Long-Term Survival after Surgery for Breast Cancer: A Nationwide Retrospective Cohort Study in South Korea / 한국유방암학회지

ABSTRACT

PURPOSE: The aim of this article was to evaluate the impact of the Charlson Comorbidity Index (CCI) on long-term survival after surgery for breast cancer in South Korea. METHODS: The study subjects were 29,562 women patients aged 20 years and older that underwent surgery for breast cancer between 2002 and 2005. The data were obtained from claims submitted to the National Health Insurance. All patients were censored at the follow-up cutoff date of June 30, 2006. Survival curves were estimated by the Kaplan-Meier method. Cox proportional hazards models were used to explore the impact of CCI on all-cause mortality. RESULTS: After a follow-up time of 47 months, higher all-cause mortality was associated with an increasing CCI. In terms of the 4-year survival rate, among patients with CCI=1, it was 91.1%, among patients with CCI=2 it was 87.8%, and those patients with CCI> or =3 it was 80.2%. Multivariate Cox proportional hazard analysis showed that CCI=1 (hazard ratios [HR], 1.10; 95% confidence interval [CI], 0.97-1.25), CCI=2 (HR, 1.61; 95% CI, 1.31-1.97) and CCI> or =3 (HR, 2.27; 95% CI, 1.59-3.24), were associated with long-term survival. CONCLUSION: CCI is a strong predictor of long-term survival after surgery for breast cancer. We recommend the use of a validated comorbidity index in the selection of patients for breast surgery.