Colorectal cancer is the second most common cancer in men and women in Ireland. Over 2,500 cases are diagnosed each year.¹ By 2045, the National Cancer Registry of Ireland (NCRI) projects this will increase to 3,464 in males and 2,329 in females.²

Currently in Ireland, the risk of developing colorectal cancer up to the age of 74 is 5% in males and 3% in females. The average five-year survival is 62.6%.¹ At present, just 44% of all cases are diagnosed at stage I or II but one of the aims of the National Cancer Strategy 2017-2026 is to increase the percentage of colorectal cancers diagnosed at stage I or II by 10% by the year 2020.³

Risk factors

Certain lifestyle factors increase the risk of developing colorectal cancer. These include smoking, alcohol consumption, a diet high in processed red meat and low in fibre, lack of exercise and greater body fatness.

Family history can also significantly increase the risk of colorectal cancer for some people. In the case of bowel cancer, family history means one first-degree relative (ie. sibling, parent or child) diagnosed with colorectal cancer before the age of 50 years, two or more relatives with colorectal or endometrial cancer (one of these should be a first-degree relative of the patient and they should be first-degree relatives of each other), or a family history of colorectal cancer syndrome such as Lynch Syndrome or familial adenomatous polyposis (FAP).

FAP accounts for about 1% of cases of bowel cancer.  Untreated, people with FAP are likely to develop bowel cancer by their early 40s while Lynch syndrome, a rare genetic condition that increases the risk of colon cancer, accounts for 2-4% of all cases of colorectal cancer.

Having an inflammatory bowel disease, ie Crohn’s or ulcerative colitis, also increases the risk of developing colon cancer. HPV is a known risk factor for anal cancer. 

Bowelscreen

Bowelscreen, the national bowel screening programme, was established in 2012 with the aim of reducing bowel cancer mortality in Ireland. This programme is open to all men and women aged 60-69 years in Ireland.

GP referral pathway

The National Cancer Control Programme (NCCP) and the HSE Endoscopy Programme have developed new guidelines for GPs to refer patients directly to endoscopy in cases where colorectal cancer is suspected.  The recently-published HSE guidelines⁴ – GP Referral Pathway for Suspected Colorectal Cancer – were finalised in early 2019 and have been disseminated throughout the year. Some hospitals are already accepting electronic referrals for this service, including St James’s Hospital Dublin, Beaumont Hospital, St Vincent’s University Hospital and Connolly Hospital, Blanchardstown. It is anticipated that electronic referral will be enabled for direct-access endoscopy countrywide.

Who to refer

The following criteria will help GPs identify which patients are appropriate for direct referral for endoscopy for suspected bowel cancer. Where a patient does not meet the criteria below but nonetheless has signs and symptoms that their GP feels are worrying for colorectal cancer, they may be referred to the local gastroenterology or colorectal out-patient clinic:

Patients aged 60 years or older

• Persistent rectal bleeding (ie. bleeding that has been present for > 6 weeks)
• Change in bowel habit lasting > 6 weeks
• Unexplained significant weight loss with other symptoms suggestive of colorectal cancer
• Patients aged between 40 and 60 years
• Rectal bleeding and a change in bowel habit for > 6 weeks
• Patients aged < 40 years
• Unexplained rectal bleeding and/or change in bowel habit
• A family history of colorectal cancer or inflammatory bowel disease.
• In this context, a family history means:
• One first-degree relative (ie. sibling, parent or child) diagnosed with colorectal cancer under the age of 50 years
• Two or more relatives with colorectal or endometrial cancer. One of these should be a first degree relative of the patient and they should be first degree relatives of each other
• A family history of colorectal cancer syndrome such as Lynch syndrome or FAP

Iron deficiency anaemia

Refer for direct access endoscopy in the case of iron-deficiency anaemia (ie. anaemia considered on the basis of history or clinical examination in primary care not to be related to other sources of blood loss). 

In this context, iron deficiency anaemia is considered to be a haemoglobin at the following level:

Male (any age) less than or equal to Hb 11g/dl

Female (non-menstruating) less than or equal to Hb 10g/dl.

Where iron deficiency anaemia is the sole reason for referral, a ferritin level must be included with the referral.

Direct referral for endoscopy is not appropriate for all patients with suspicious signs and symptoms. Patients who have a clearly palpable abdominal, rectal or anal mass, or who have visible anal ulceration, should be referred directly to colorectal or gastroenterology outpatients. 

Similarly, patients who are found incidentally to have suspected colorectal cancer on abdominal/pelvic imaging +/- metastatic disease should not be referred directly for endoscopy but be assessed in a colorectal clinic, followed by discussion at a colorectal MDT meeting.

Patients with suspected bowel obstruction or perforation should be referred urgently to an emergency department.

When is direct referral for colonoscopy not applicable?

If your patient has signs and/or symptoms that do not meet the above criteria but that you nevertheless feel are worrying about bowel cancer, they can be referred to the local gastroenterology or colorectal outpatient clinic.

Direct referral for colonoscopy is generally not applicable for patients who have the following: constipation as an isolated symptom; diarrhoea of < six weeks duration; abdominal pain in the absence of altered bowel habit; anal symptoms such as prolapsed piles, rectal prolapse, anal fissure; low ferritin in patients > 50 years of age but with a normal haemoglobin (in these patients, it is still advisable to consider the need for endoscopy, particularly in males); or a young person presenting with bloody diarrhoea. This usually requires urgent referral to gastroenterology services as they may be suffering from IBD.

Patients whose colonoscopy referrals are triaged as urgent will be offered an appointment within four weeks where possible. Routine referrals will be seen within about 13 weeks.

Conclusion

While many factors impact on survival such as age, cancer type and fitness level, it is known that survival for bowel cancer is strongly related to stage of disease at diagnosis. In men, five-year survival ranges from 95% at stage I, to 7% at stage IV,² while for women five-year survival ranges from 100% at stage I to 8% at stage IV.³

It is the aim of these guidelines to increase the number of cases of colorectal cancer diagnosed at an early stage and to ultimately prolong survival from this disease. A copy of the pathway can be found at www.hse.ie/cancer

1. National Cancer Registry Annual Report November 2018
2. Cancer Incidence Projections for Ireland 2020-2045. NCRI
3. National Cancer Strategy 2017-2026
4. NCCP GP Referral Pathway for Suspected Colorectal Cancer. HSE 2019. Available at www.hse.ie/cancer