Presentation: Patient with polyposis

A 38-year-old man with rectal bleeding, abdominal pain and a positive faecal immunochemical test (FIT) undergoes colonoscopy. Seven adenomatous polyps measuring 5mm–10mm are detected and completely excised. He has no family history of colorectal cancer.

• Polyps should be histologically confirmed prior to referral for genomic testing.
• Genomic testing for a patient with colorectal polyposis should be considered by a clinical geneticist, gastroenterologist or colorectal surgeon if any of the following National Genomic Test Directory eligibility criteria are met:
  • any colorectal, small bowel or endometrial cancer diagnosed under the age of 40;
  • ≥5 adenomatous polyps and colorectal cancer;
  • ≥5 adenomatous polyps (under 40 years old);
  • ≥10 adenomatous polyps (under 60 years old);
  • ≥20 adenomatous polyps (age ≥60 years old);
  • ≥5 adenomatous polyps (under 60 years old) and a first-degree relative with either ≥5 adenomatous polyps or colorectal cancer (under 60 years old); or
  • a clinical diagnosis of serrated polyposis syndrome if:
    • the patient is aged <50 years old; or
    • two or more first-degree relative(s) are/have been affected by serrated polyposis syndrome; or
    • there’s evidence of dysplasia within any polyp; or
  • hamartomatous polyposis syndromes:
    • ≥5 hamartomatous polyps of the colorectum; or
    • ≥2 hamartomatous polyps throughout the GI tract; or
    • ≥1 hamartomatous polyp(s) and a first- or second-degree relative has a hamartomatous polyp.
• Genomic testing may occasionally be warranted outside of these criteria, following discussion with your local Genomic Laboratory Hub.
• Where patients with polyposis do not meet eligibility criteria for genomic testing, they may still require increased endoscopic surveillance. Please refer to the post-polypectomy and post-colorectal cancer resection surveillance guidelines by Rutter and others for more information.
• For detailed guidance on other aspects of clinical management for patients with multiple colorectal adenomas (MCRAs) and serrated polyposis syndrome (SPS), please refer to the management of hereditary colorectal cancer guidelines by Monahan and others.

• Consult the National Genomic Test Directory. From here you can access the rare and inherited disease eligibility criteria for information about individual tests and their associated eligibility criteria. You can also access a spreadsheet containing details of all available tests.
  • For information about how to arrange testing in Wales, Scotland or Northern Ireland, see our dedicated Knowledge Hub resource.
• To find out which genes are included on different gene panels, see the NHS Genomic Medicine Service (GMS) Signed Off Panels Resource.
• For investigation of possible germline polyposis syndrome, the appropriate panel to choose is R211 Inherited polyposis and early onset colorectal cancer – germline test: This is a gene panel test that screens for a focused number of genes related to polyposis syndromes. These tests are performed on a singleton basis.
• For tests such as R211, which do not include whole genome sequencing, you can use your local Genomic Laboratory Hub test order and consent (record of discussion) forms.
• Patients with a genetic diagnosis of polyposis should be referred to a regional genetics service and to St Mark’s Hospital Polyposis Registry or another clinical service within the rare disease collaborative network for polyposis.
• Information about patient eligibility and test indications was correct at the time of writing. When requesting a test, please refer to the National Genomic Test Directory to confirm the right test for your patient.

For clinicians

• St Mark’s Hospital Polyposis Registry
• St Mark’s Hospital: The St Mark’s Centre for Familial Intestinal Cancer
• UK Cancer Genetics Group: Leaflets and guidelines
• UK Cancer Genetics Group: Rare Disease Collaborative Networks

References:

• Monahan KJ, Bradshaw N, Dolwani S and others. ‘Guidelines for the management of hereditary colorectal cancer from the British Society of Gastroenterology (BSG)/Association of Coloproctology of Great Britain and Ireland (ACPGBI)/United Kingdom Cancer Genetics Group (UKCGG)‘. Gut 2020: volume 69, issue 3, pages 411–444. DOI: 10.1136/gutjnl-2019-319915
• Rutter MD, East J, Rees CJ and others. ‘British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer resection surveillance guidelines‘. Gut 2020: volume 69, issue 2, pages 201–223. DOI: 10.1136/gutjnl-2019-319858

For patients

• GUTS UK: Polyps in the bowel