Urgent referral Expect a consultation within 2 weeks and a definitive diagnostic workup to be completed within 4 weeks of referral if a patient has at least 1 of the following: Palpable rectal mass suspicious for CRC Abnormal abdominal imaging result causing suspicion of CRC Semiurgent referral Expect a consultation within 4 weeks and a definitive diagnostic workup to be completed within 8 weeks of referral if a patient has at least 1 of the following: Unexplained rectal bleeding with at least 1 of -dark rectal bleeding, -rectal bleeding mixed with stool, -rectal bleeding in the absence of perianal symptoms, -rectal bleeding and a change in bowel habits, or -rectal bleeding and weight loss Unexplained IDA (hemoglobin of ≤ 110 g/L for men or ≤ 100 g/L for nonmenstruating women and iron level below the normal range) A high level of suspicion of CRC because of an unexplained sign or symptom but not meeting the above criteria Referring physicians should include in the consultation request information about anything that can increase the likelihood of CRC: All presenting signs and symptoms Patient age ≥ 60 years Male sex Personal history of colorectal polyps or IBD, or family history of CRC in a first-degree relative Patients not meeting referral criteria If the unexplained signs or symptoms of patients do not meet the criteria for referral but, based on clinical judgment, there remains a low level of suspicion of CRC, then the following are appropriate: Treat the sign or symptom, if applicable Review and ensure resolution of symptoms within 4 to 6 weeks If signs or symptoms have not resolved in 4 to 6 weeks, then confer with a specialist or refer semiurgently A 3-stool sample FOBT can be ordered in the absence of recent CRC screening and in the absence of current active rectal bleeding. If the result is positive, refer semiurgently. A negative result does not rule out CRC Excessive wait times In situations where wait times for specialists to perform colonoscopy are considered excessive, referring physicians can order the following (depending on locally available resources): CT colonography DCBE This is best done in coordination with the specialist, if possible. Normal or negative results should not lead to a cancellation of the consultation. Positive results might facilitate more timely investigation of a patient

CRC—colorectal cancer, CT—computed tomography, DCBE—double-contrast barium enema, FOBT—fecal occult blood test, IBD—inflammatory bowel disease, IDA—iron deficiency anemia.