Purpose: The National Comprehensive Cancer Network recommends chemotherapy for all stage III colon cancer patients. In fact, the American Society of Clinical Oncology quality program and the American College of Surgeons use administration of chemotherapy in stage III colon cancer as a quality measure. Though adjuvant chemotherapy improves overall survival in stage III colon cancer, prior studies have shown that it is underused. Its use was reported around 60%, with the use lower in females, the elderly, and African Americans. Our study uses a larger patient population from more recent years. We also analyzed different factors that may influence its use, including insurance type.
Methods: This is a retrospective study of stage 3 colon cancer patients diagnosed nationwide (n = 207,718) as well as at VA Nebraska-Western Iowa Health Care System (n = 10) in the National Cancer Data Base (NCDB). While the national data were available between 2000 and 2011, the data from the VAMC were available for 2010 and 2011. The NCDB contains about 70% of new cancer diagnosis in the U.S., deriving its data from > 1,500 American College of Surgeons-accredited cancer programs. Chi-square test was used to determine any difference in characteristics of patients who did or did not receive chemotherapy.
Results: One-fourth of all colon cancer patients at the VAMC were in stage III. Ninety percent of these patients received adjuvant chemotherapy. Nationwide, only 65% of such patients received adjuvant chemotherapy, with its use lower in elderly patients, whites, females, patients with one or more comorbidities, those with longer travel to treatment facility, and those with Medicare insurance, lower education, and lower income levels (all P < .05). Nonwhite and uninsured were more likely to be aged < 60 years.
Conclusions: This is the largest study to determine the use of chemotherapy in stage III colon cancer, both nationally and at local VAMC. Though its use nationwide has increased in recent years, the overall use is still low. Patient characteristics such as age, race, and gender, as well as socioeconomic factors influence its use. These findings have important implications for health care reform.
