The American Society of Clinical Oncology (ASCO) sets guidelines for follow-up testing to detect recurring cancer after the completion of treatment. The following guidelines are based on ASCO’s 2005 updated recommendations.
Most colorectal cancer recurrences happen within 3 years after surgery. ASCO recommends that patients see their doctor for a physical examination every 3 – 6 months for the first 3 years, every 6 months for the fourth and fifth years, and at the doctors’ and patients’ discretion during subsequent years.
Patients should have a colonoscopy 3 years after surgery. If the findings are normal, patients should then receive a colonoscopy every 5 years. Some patients with hereditary types of colorectal cancer may require more frequent screenings.
A flexible sigmoidoscopy is recommended every 6 months for 5 years for patients with Stage II or III rectal cancer who did not receive radiation therapy.
Carcinoembryonic antigen (CEA) levels should be measured every 3 months after surgery for 3 years in patients with Stage II or III cancer. High CEA levels in the blood may indicate that the cancer has spread to other parts of the body.
Patients at high risk for cancer recurrence should receive an annual computerized tomography (CT) scan for the first 3 years after treatment. The CT scan can help determine if cancer has spread to the lungs or liver. Patients who have had rectal cancer, and did not have radiation therapy, should receive a pelvic CT scan. The scan is not recommended for most lower-risk patients with Stage I or II colorectal cancer.
ASCO does not recommend other follow-up blood tests such as complete blood count (CBC), liver function tests, fecal occult blood tests (FOBT). There appears to be no additional benefit for these tests.
Review Date: 03/06/2007
Reviewed By: A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously reviewed by Harvey Simon, M.D., Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital (9/1/2006).