Surgery and adjuvant chemotherapy use among veterans with colon cancer: Insights from a California study

Purpose: US veterans have been shown to be a vulnerable population with high cancer rates, and cancer care quality in Veterans Affairs (VA) hospitals is the focus of a congressionally mandated review. We examined rates of surgery and chemotherapy use among veterans with colon cancer at VA and non-VA facilities in California to gain insight into factors associated with quality of cancer care. Methods: A retrospective cohort of incident colon cancer patients from the California Cancer Registry, who were ≥ 66 years old and eligible to use VA and Medicare between 1999 and 2001, were observed for 6 months after diagnosis. Results: Among 601 veterans with colon cancer, 72% were initially diagnosed and treated in non-VA facilities. Among veterans with stage I to III cancer, those diagnosed and initially treated in VA facilities experienced similar colectomy rates as those at non-VA facilities. Stage III patients diagnosed and initially treated in VA versus non-VA facilities had similar odds of receiving adjuvant chemotherapy. In both settings, older patients had lower odds of receiving chemotherapy than their younger counterparts even when race and comorbidity were considered (age 76 to 85 years: odds ratio [OR] = 0.18; 95% CI, 0.07 to 0.46; age ≥ 86 years: OR = 0.17; 95% CI, 0.04 to 0.73). Conclusion: In California, older veterans with colon cancer used both VA and non-VA facilities for cancer treatment, and odds of receiving cancer-directed surgery and chemotherapy were similar in both systems. Among stage III patients, older age lowered odds of receiving adjuvant chemotherapy in both systems. Further studies should continue to explore potential health system effects on quality of colon cancer care across the United States.