Post-treatment surveillance in a large cohort of patients with colon cancer.

OBJECTIVES: To determine how patients complied with different components of guideline-recommended post-treatment surveillance in a large nationwide population-based cohort of patients with colon cancer. STUDY
DESIGN: Retrospective cohort study.
METHODS: We used the linked Surveillance, Epidemiology, and End Results-Medicare database to identify patients 66 years or older diagnosed as having stage I to stage III colon adenocarcinoma between January 2000 and June 2002 with a follow-up duration of at least 3.5 years. After tumor resection, patients who completed at least 2 office visits per year for 3 years, at least 2 carcinoembryonic antigen tests per year (in the first and second years of follow-up), and at least 1 colonoscopy within 3 years were defined as meeting the recommended post-treatment care.
RESULTS: We identified 7348 patients, with a median follow-up duration of 59 months. Adherence to post-treatment surveillance was 83.9% for office visits, 29.4% for carcinoembryonic antigen tests, and 74.3% for colonoscopy. Younger age at diagnosis, white race/ethnicity, married status, advanced tumor stage, fewer comorbidities, and chemotherapy use were significantly associated with guideline adherence.
CONCLUSIONS: Adherence to colon cancer posttreatment surveillance was low, although proportions of patients complying with office visits and colonoscopy were reasonably high. Underlying reasons for noncompliance, which varied by type of service, may need further investigation.