Surveillance strategies following curative resection and non-operative approach of rectal cancer: How and how long? Review of current recommendations

Table 3 Summary of current surveillance guidelines from specialty societies

Guideline	MH & PE	CEA	Abdomen imaging	Chest imaging	Colonoscopy
ASCO[13]	Every 3-6 mo for 5 yr	Every 3-6 mo for 5 yr	CT of abdomen and pelvis annually for 3 yr, for high-risk patients every 6-12 mo for 3 years and then annually for 2 yr	CT of chest annually for 3 yr, for high-risk patients every 6-12 mo for 3 yr	Colonoscopy at 1 yr, subsequently according findings and every 5 yr if normal. Rectosigmoidoscopy every 6 mo for 5 yr in rectal cancer not irradiated
ASCR[4]	Every 3-6 mo for 2 yr, then every 6 mo for 3 yr	Every 3-6 mo for 2 yr, then every 6 mo for 3 yr	CT of abdomen and pelvis 2 times in 5 yr, for high-risk patients annually for 5 yr	CT of chest 2 times in 5 yr, for high-risk patients annually for 5 yr	Colonoscopy at 1 yr, subsequently according findings and every 5 yr if normal. Rectosigmoidoscopy (+/- ERUS) every 6-12 mo for 3 to 5 yr for patients treated with TME; every 6 mo in patients treated with local excision
ESMO[12]	Every 6 mo for 2 yr	Every 6 mo for 3 yr	CT of abdomen and pelvis 2 times within 3 yr	CT of chest 2 times within 3 yr	Colonoscopy every 5 yr up to age 75
ACPGI[11]	No recommendation for frequency	Every 6 mo for 3 yr	CT of abdomen and pelvis 2 times within 3 yr	CT of chest 2 times within 3 yr	Colonoscopy at 1 yr subsequently according findings and every 5 yr if normal
NCCN[14]	Every 3-6 mo for 2 yr, then every 6 mo for 3 yr for stage II or greater	Every 3-6 mo for 2 yr, then every 6 mo for 3 yr for stage II or greater	CT of abdomen and pelvis every 3-6 mo for 2 yr, then every 6-12 mo for 3 yr	CT of chest every 3-6 mo for 2 yr, then every 6-12 mo for 3 yr	Colonoscopy at 1 yr, repeat in 3 yr then every 5 yr, Proctoscopy (with ERUS or MRI) every 3-6 mo for 2 yr, then every 6 mo for 3 yr for patients treated with transanal excision
ESCP[15]	No recommendation for frequency. Until 5 yr after surgery with a more frequent regimen in the first 2 yr to 3 yr	Every 3–6 mo for 2–3 yr, then every 6-12 mo until 5 yr after surgery	CT abdomen alternating with US for at least 5 yr with a more frequent regimen in the first 2-3 yr	CT of chest alternating with CXR every 3-12 mo for at least 5 yr after surgery	No recommendation for colonoscopy and proctoscopy

ACPGI: The association of Coloproctology of Great Britain and Ireland; ASCO: American Society of Oncology; ASCRS: American Society of Colon Rectal Surgeon; CEA: Carcinoembryonic antigen; CT: Computed tomography; CXR: Conventional chest radiography; ERUS: Endorectal ultrasound; ESMO: European Society for Medical Oncology; ESCP: European Society of Coloproctology; mo: months; MH & PE: Medical history and physical examination; MRI: Magnetic resonance imaging; NCCN: National Comprehensive Cancer Network; TME: Total mesorectal excision; US: Ultrasonography; yr: years.