Acuity and Survival in Colon Cancer Surgery

Abstract

Reports indicate that up to 40% of patients with colon cancer require nonelective resection, which has been shown to portend worse long-term prognosis compared with elective resection. We used a national database to identify specific preoperative, perioperative, and postoperative factors mediating the acuity-survival relationship in an effort to identify areas of medical practice that can serve as targets for improvement in cancer care. We used the Surveillance, Epidemiology and End Results-Medicare-linked database to identify non-health maintenance organization-enrolled people aged 66 years and older who were diagnosed with stages I to III colon cancer between 1996 and 2003 (N = 30,685). Using stepwise, multivariate Cox regression, disease-specific survival was compared in patients undergoing elective vs nonelective resection. Adjustment for preoperative, perioperative, and postoperative variables was performed to identify factors contributing to the acuity-survival relationship. Five-year disease-specific survival was 86.3% after elective and 75.4% after nonelective colon resection (hazard ratio, 1.92; P < .001). A significant proportion of this disparity was the result of differences in stage and patient characteristics, particularly age and comorbidity burden, at the time of resection. Differences in adequacy of nodal assessment and the use of surveillance colonoscopy and adjuvant chemotherapy, however, also contributed to the disparity. After adjustment for these factors, the hazard ratio for nonelective resection was 1.30 (P < .001). Nonelective resection of colon cancer is associated with poor long-term prognosis compared with elective resection. Disease-specific survival among patients undergoing nonelective surgery may be improved by addressing insufficient nodal assessment, inadequate follow-up care, and underutilization of appropriate, adjuvant chemotherapy.