Purpose: Appropriate use of adjuvant chemotherapy is a widely recognized quality measure of colorectal cancer care. The objective of this study was to test the hypothesis that surgical complications are associated with omission of chemotherapy for colorectal cancer.
Methods: We used the 1998 to 2005 Surveillance, Epidemiology and End Results-Medicare database to study adjuvant chemotherapy use among patients with stage III colorectal cancer who underwent surgical resection. Chemotherapy use was compared between patients with and without complications. Univariate analyses and multiple logistic regression were used to test the association between complications and chemotherapy omission, while adjusting for demographics, comorbidity, and other factors. Associations between complications and time to chemotherapy were also studied.
Results: We identified 17,108 eligible patients with stage III colorectal cancer (median age, 75 y; 24% rectal/rectosigmoid). Using a parsimonious list of complication codes, 18% of patients had ≥ 1 complication. Thirteen percent of patients had medical complications and 3.8% of patients had complications requiring reoperation or another procedure. Adjuvant chemotherapy was omitted among 46% of patients with complications, compared with 31% of patients with no complications (P < .0001). Having a complication was independently associated with omission of chemotherapy in multivariable analysis (adjusted OR, 1.76; 95% CI 1.59-1.95). Other factors significantly associated with chemotherapy omission were age, race, marital status, urgent/emergent admission, and type of operation. Risk ratios increase with multiple complications (P < .0001). Complications were also associated with an increased risk of chemotherapy delay (P < .0001).
Conclusions: Surgical complications are independently associated with omission of chemotherapy for stage III colorectal cancer and with a delay in adjuvant chemotherapy. These data suggest that complications of colorectal surgery may affect both short- and long-term cancer outcomes. Thus, the implementation of quality improvement measures that effectively reduce perioperative complications may also provide a long-term cancer survival benefit.