This guideline provides follow-up recommendations for patients after curative resection of colorectal cancer (CRC) or polypectomy. These recommendations are intended to rationalize follow-up of the initial cancer and to prevent the development of additional colorectal cancer. They do not apply to patients with familial adenomatous polyposis (FAP), hereditary non-polyposis colon cancer (HNPCC) or inflammatory bowel disease. Recommendations for these patients and for the detection of colorectal neoplasms in asymptomatic patients are found in the guideline, BCGuidelines.ca -Colorectal Screening for Cancer Prevention in Asymptomatic Patients.#
- Removal of adenomas can prevent CRCs.
- Individuals with colorectal adenomas or carcinoma are at high risk for recurrence.
- Colonoscopy is the key follow-up test to detect new primary cancers or adenomas.
- Patients followed by colonoscopy do not require fecal occult blood testing (FOBT).
- Early detection and treatment of CRC metastases may prolong survival.
By definition all adenomatous polyps have dysplasia. Detection and removal of adenomas has been clearly demonstrated to reduce CRC mortality, and identification of cancer at an early stage markedly increases survival rates. Patients who have had CRC or advanced adenomas are at increased risk of recurrence and require close follow-up. The most important phase of follow-up is the first 2-3 years after the primary tumour resection as during this time the majority of recurrences will become apparent. 1 The risk of an adenoma becoming malignant is greatest for "advanced" adenomas.
- tubular adenomas > 1 cm,
- villous adenomas,
- adenomas with high grade dysplasia (HGD),
- sessile serrated polyps > 1 cm,
- sessile serrated polyps with dysplasia, or - traditional serrated adenoma.
Individuals with multiple (>3) adenomas of any size are also at increased risk. 2 It generally takes 5-10 years for a small adenoma to develop into a malignancy; cancer may be prevented by adenoma removal.
The majority of CRCs arise from adenomas, the 'adenoma-carcinoma sequence'. Two major types of polyps are found in the colon and rectum: adenomas and hyperplastic polyps. Hyperplastic polyps are considered to have no malignant potential. Patients with 1 or 2 small (< 1 cm) tubular adenomas with only low-grade dysplasia Follow-up colonoscopy in 5 to 10 years. Timing within this interval should be based on other clinical factors (e.g., previous colonoscopy findings, family history, patient preferences, judgment of the physician).
Patients with 1 or more sessile serrated polyps < 1 cm with no dysplasia Follow-up colonoscopy in 5 years.
Patients with 3 to 10 tubular adenomas or any advanced adenomas (tubular adenomas > 1 cm, villous adenomas, adenoma with HGD, sessile serrated polyps > 1 cm, sessile serrated polyps with dysplasia, or traditional serrated adenoma)
Follow-up colonoscopy in 3 years provided that adenomas are completely removed. If the follow-up colonoscopy is normal or shows only 1 or 2 small (< 1 cm) tubular adenomas with lowgrade dysplasia, the interval for the subsequent examination should be 5 years.
Patients with sessile adenomas where complete removal is uncertain Follow-up colonoscopy within 6 months to verify complete removal. Once complete removal has been established, subsequent surveillance should be as for advanced adenomas.
Risk Group Surveillance Recommendations Patients

# Post-Cancer Resection
The goal of follow-up after resection is to identify recurrent disease or metastases and to detect subsequent adenomas. These recommendations are generally expert consensus-based. Patients with significant co-morbidities, very advanced age or limited 5 year life expectancy are not routinely offered surveillance.

# Follow-up visits with Family Physician
Focused history and physical examination are recommended every 3 to 6 months for 2 years, and then every 6 months for a total of 5 years. 5,6 It is recommended that each follow-up visit include:
- History to elicit gastrointestinal and constitutional symptoms, including nutritional status.
- Physical examination with particular attention to the abdomen, liver and rectal evaluation (or perineal inspection and palpation in those patients who have had an abdominal perineal resection). - Routine laboratory investigations, such as liver chemistry, in the absence of symptoms are not useful.

# Controversies in Care
Aspirin (& other NSAIDS) has been shown to reduce the incidence of subsequent colorectal adenomas and cancer, but because of potential adverse effects it is currently not recommended. 7

# Tumour Markers
A carcinoembryonic antigen (CEA) test is recommended at diagnosis of CRC and repeated to monitor rising levels of CEA (at least doubling) which can indicate hepatic or pulmonary metastases. Eligible patients for surveillance with CEA are those with stage II or III tumors (i.e., tumour through the bowel wall or metastatic to locoregional lymph nodes). These patients are offered CEA every 3 months for the first 3 years and every 6 months during years 4 and 5. No CEA is required beyond 5 years.

# Imaging and X-rays
Liver imaging, by ultrasound or CT scan (CT preferable), 10,11 is recommended every 6 months for the first 3 years, then once per year for 2 more years. 12 For those with advanced stage cancers or undergoing chemotherapy, follow the recommendations of the oncologist. 5,13 Routine CT scanning is not recommended beyond 5 years.
There is little evidence to show a survival benefit for routine chest x-ray for post CRC resection patients. 14 A chest CT scan is recommended for every 12 months for the first 3 years in cases of advanced cancer or rectal cancer. 5,6 Colonoscopy Patients with CRC should undergo a complete cancer and polyp clearing colonoscopy prior to or within 12 months of surgical resection of the colorectal tumour. A colonoscopy should follow at one year after resection or clearing colonoscopy. 4,6 If the one year colonoscopy is normal, the next colonoscopy should be performed in 3 years; if those results are normal, the next colonoscopy should be performed in 5 years 4,6 to look for another primary colorectal malignancy or adenomatous polyps. After the one year colonoscopy, the intervals between subsequent colonoscopies may be shortened if there is evidence of HNPCC or if adenoma findings warrant earlier colonoscopy.
Performance of FOBT is unnecessary in patients undergoing colonoscopic surveillance. 9

# Surveillance After 5 Years
Continued surveillance is recommended with a colonoscopy conducted every 5 years. There is no place for FOBT in this population.
- BC Cancer Agency, Follow- This guideline was developed by the Guidelines and Protocols Advisory Committee, approved by the British Columbia Medical Association, and adopted by the Medical Services Commission.
BCGuidelines.ca: Follow-Up of Colorectal Polyps or Cancer (2013) 5
The principles of the Guidelines and Protocols Advisory Committee are to: