Impact of comorbidities using Adult Comorbidity Evaluation-27 (ACE-27) score on survival in stage II colon cancer: Age, TNM staging, and pathological high risk-disease.

Abstract

659 Background: Impact of comorbidities is identified in stage III colon cancer patients (CCPs) receiving adjuvant chemotherapy (Wildes et al, PMID 21113435) but is not well defined in predicting overall survival (OS) in stage II CCPs undergoing either adjuvant treatment or observation depending upon high-risk disease. The goal of this study was to identify impact of comorbidities on OS in this potentially curable disease using ACE-27 score, which uses 27 different patient comorbid conditions has been developed and validated by Piccirrillo et al at Barnes Jewish Hospital (BJH) (PMID: 24933715). Methods: We identified stage II CCPs treated at BJH, Siteman cancer center from January 1, 1996 to October 31st, 2013 from BJH oncology data cancer registry. The primary outcome was OS, defined as the time from date of surgery to death from any cause, censored at the time of last follow-up. Patient comorbidities at diagnosis were recorded using ACE-27 score, assigning a comorbidity score of none, mild, moderate and severe to the patients. Survival analysis was done using Cox proportional hazard modelling using STATA/SE 11.2 software. Pathological high risk features such as T4 lesions, < 12 LN, perineural, lymphovascular invasion, positive margins & perforation/obstruction were identified. Results: Out of 579 stage II CCPs, 48% male and 51% were females. High risk features were identified in 45% of patients. ACE-27 comorbidity score of none (n = 146), mild (n = 229), moderate (n = 132) and severe (n = 72) was calculated. 497 patients had T3N0M0 and 82 had T4N0M0 staging. Cox regression hazard model using histological prognostic factors, age at surgery, sex, race, prior cancer history and TNM staging showed that ACE-27 score of moderate and severe were independent predictors of OS with a hazard ratio of 1.6 (95% CI 1.0-2.4), P = 0.036 and 2.5 (95% CI 1.5-4.0), P = 0.00 respectively. Conclusions: Highest commodity burden using ACE-27 comorbidity score was associated with poor OS in stage II CCPs and was independent of other prognostic risk factors including high-risk features. Treatment related mortality will be calculated in patients with high risk disease.