Lower gastrointestinal cancers

Urgent suspicion of cancer (USC) referral

Refer a person with any of the following to the Colorectal Service as a USC:

qFIT test result of 20 or more micrograms of haemoglobin per gram of faeces (≥20µgHb/g faeces) in the presence of colorectal symptoms or iron deficiency anaemia
Symptoms that qualify for a qFIT test and either:
- the local pathway is secondary care qFIT testing or assessment
- the person is unable or unwilling to complete a test
Unexplained abdominal mass
Palpable anorectal mass
Unexplained anal ulceration

Assessment for suspected lower GI cancers

Clinical features of colorectal cancer include:

Rectal bleeding
Change in bowel habit
Weight loss
Abdominal pain
Rectal or abdominal mass
Iron deficiency anaemia

Many of these are common presentations in primary care. The published data on positive predictive value (PPV) for symptoms of suspected colorectal cancer are included in the reference section.^15,16,50,51

If lower GI cancer is suspected:

Perform an abdominal and rectal examination
Arrange blood tests for renal function, liver function and full blood count plus ferritin/iron studies if anaemic⁹

Quantitative faecal immunochemical test (qFIT)

The qFIT detects human haemoglobin breakdown products in the stool. It should be used in people with clinical features of suspected colorectal cancer to identify those who are more likely to have cancer and therefore need investigation as a USC.

A qFIT should be arranged for a person with any of the following, using the local pathway:

Repeated anorectal bleeding without an obvious anal cause
Blood mixed through the stool
Change in bowel habit for four weeks or more, particularly looser or more frequent stool
Iron deficiency anaemia (haemoglobin below reference range and ferritin <30mg/l or confirmed on iron studies)
Persistent abdominal pain (four weeks or more) and weight loss (5% or more of body weight or strong clinical suspicion)

A qFIT is not indicated for a rectal or abdominal mass or unexplained anal ulceration.

In the context of other symptoms, a qFIT should only be arranged in line with national guidelines: Quantitative Faecal Immunohistochemical Testing (qFIT) 2024.

Good practice points

qFIT testing:

Quantitative Faecal Immunohistochemical Testing (qFIT) 2024 provides advice on qFIT testing for new colorectal symptoms, iron deficiency anaemia, thresholds for referral and when repeat testing is recommended. It also defines the clinical scenarios in which a qFIT is not indicated.

Where possible, the referrer should provide the numerical value of the qFIT when referring to secondary care to allow effective triage.

If a qFIT cannot be arranged but the patient is being referred as a USC to secondary care, the reason for the absence of a qFIT result should be included in the referral. It should be made clear on referral if the person is unable or unwilling to comply. There should be safety netting processes for those who do not return their qFIT as there is a similar colorectal cancer prevalence in this group compared with those who return their qFIT⁵².

A person with iron deficiency anaemia and a normal qFIT may still require investigation. Refer according to local pathways.

Hereditary colon cancer:

See Regional Genetics Centres for advice on referral for people with hereditary colorectal cancer, Lynch Syndrome or polyposis.

Overlap with other pathways:

People with intra-abdominal cancer can present with symptoms that overlap. Please see Upper gastrointestinal cancer guideline (including hepatopancreatobiliary cancer), Ovarian cancer guideline and Kidney cancer guideline. This is particularly important if a person presents with abdominal pain, bloating and/or weight loss but has a negative qFIT. In this case consider alternative pathways (e.g. upper GI, ovarian or kidney cancer) or arrange imaging studies.

Thrombocytosis is a risk factor for cancer. If present, there should be clinical assessment for causes¹⁷. See the section on thrombocytosis in Referral process/Further considerations for assessment and referral.

Anaemia that is not iron deficient should prompt assessment for alternative diagnoses and monitoring if required.

Calprotectin is a biomarker for inflammation and is used to differentiate between inflammatory bowel disease (IBD) and functional gastrointestinal disorders (e.g. irritable bowel syndrome). A calprotectin test should be considered for people with persistent loose stools. Please see the national guidelines: Inflammatory bowel disease (IBD) pathway for further investigations and/or referral to secondary care.

Background

Lower Gastrointestinal (GI) cancer includes cancers of the colon, rectum and anus.

Colorectal cancer is the fourth most common cancer in Scotland, accounting for 12% of all new cancer cases across 2021 and 2022, (when excluding non-melanoma skin cancer)¹. Later stage at diagnosis is associated with more limited treatment options and therefore worse survival.

The main pathway to diagnosis for colorectal cancer is following a symptomatic presentation in primary care. In addition, bowel screening is offered every 2 years to people aged 50 to 74. A negative bowel screening test should not prevent a USC referral for a person with symptoms outlined below.

There are inequalities in the diagnosis of colorectal cancer. Men, those aged 65 years or under, those from areas of greater deprivation and those from Asian, Black, or mixed ethnic groups are less likely to complete or return a qFIT⁴⁷. Being diagnosed via the emergency route is associated with later stage at diagnosis and worse outcomes. Evidence has also found that those who are older⁴⁸, or from areas of greater deprivation are more likely to present as an emergency⁴⁹.