MKSAP quiz: Timing of surveillance colonoscopy

This month's quiz asks readers to determine when surveillance colonoscopy should take place in a 63-year-old woman who had right hemicolectomy for colon cancer one year prior.


A 63-year-old woman is evaluated at a follow-up appointment after undergoing right hemicolectomy for colon cancer 1 year earlier. Her paternal grandfather had colon cancer diagnosed at age 75 years. She reports that she has been feeling well and takes no medication.

All physical examination findings, including vital signs, are normal.

When should this patient's next surveillance colonoscopy take place?

A. Now
B. In 1 year
C. In 3 years
D. In 5 years


MKSAP Answer and Critique

The correct answer is A. Now. This content is available to MKSAP 18 subscribers as Question 34 in the Gastroenterology and Hepatology section. More information about MKSAP is available online.

This patient's next surveillance colonoscopy should take place now (1 year after diagnosis) according to the American Gastroenterological Association (AGA) and American Society of Clinical Oncology (ASCO) guidelines. Patients who undergo a complete perioperative colonoscopy with clearing of synchronous neoplasia and curative surgical resection for colon cancer should have a subsequent surveillance colonoscopy within 1 year. If the colonoscopy is normal, the AGA recommends repeat examination in 3 years; ASCO recommends repeat examination in 5 years. If normal, colonoscopy should be repeated every 5 years thereafter until the benefit of continued surveillance is outweighed by risks and diminished life expectancy. If neoplasms are detected during any follow-up examination, then the surveillance interval should be adjusted based on polyp size, number, and histology.

Colonoscopy is the preferred modality for surveillance in patients with a personal history of colon cancer. There is insufficient evidence to support CT colonography, fecal immunochemical testing, or fecal DNA testing for surveillance after colon cancer.

Surveillance colonoscopy every 1 to 2 years is recommended in individuals with Lynch syndrome, regardless of whether the patient has a personal history of colon cancer. Lynch syndrome is unlikely because the patient's family history does not meet the Amsterdam II criteria, which require that three family members are affected by a Lynch syndrome–associated cancer, at least two successive generations are affected, one of the affected family members is a first-degree relative of the other two affected family members, and at least one cancer was diagnosed in a family member younger than age 50 years, with familial adenomatous polyposis excluded and tumors verified histologically.

A 5-year or 10-year interval is not appropriate for this patient because the risk for metachronous cancer (multiple primary tumors developing at different time intervals) is increased for about 2 to 3 years after colon cancer resection.

According the American Cancer Society's Colorectal Cancer Survivorship Care Guidelines published in 2015, a history and physical examination should be performed every 3 to 6 months for the first 2 years, then every 6 months for 5 years. After treatment for stages 1, 2, or 3 colorectal cancer, patients at high risk for recurrence (for example, with poorly differentiated histology, lymphatic or vascular invasions, or positive resection margins) should receive annual abdominal-pelvic and chest CT scans for 5 years after resection. A history and physical examination should also be performed every 3 to 6 months for 5 years. Carcinoembryonic antigen measurement is recommended every 3 to 6 months for the first 2 years, then every 6 months to 5 years if the patient is a potential candidate for further intervention. Follow-up evaluation recommendations from other expert organizations vary.

Key Point

  • After treatment of colon cancer, patients should undergo surveillance colonoscopy 1 year after diagnosis.