Colorectal Cancer

Colorectal cancer is common and one of the leading causes of cancer death.

66-year-old man presents to his general practitioner after noticing blood mixed in the stool and increased frequency of his bowel movement. He also complains of progressive fatigue and unintentional weight loss over the past several months. Initial laboratory findings suggest iron-deficiency anaemia and positive faecal occult blood test.

Key Points

• Colorectal cancer is common and one of the leading causes of cancer death.

• Common symptoms include change in bowel habit and rectal bleeding.

• Family history and familial cancer syndromes. Familial adenomatous polyposis and Lynch syndrome are key risk factors.

• Screening test is available for those aged above 60 and those at high risk.

• Colonoscopy is the standard investigation for those suspected of colorectal cancer.

• The main tumour marker is Carcino-embryonic Antigen (CEA).

• Surgical resection is the mainstay.

Introduction 

Epidemiology

Aetiology

Screening and Prevention

Diagnostic Approach : History

Diagnostic Approach : Physical Examination

Diagnostic Approach : Investigations

Differential Diagnosis

Management

Prognosis

Resources

[1] Bowel cancer statistics, Cancer Research UK, https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/bowel-cancer#heading-Three. Last accessed 8 Dec 2022.

[2] Mayer RJ, Lower Gastrointestinal Cancers, Harrison’s Principles of Internal Medicine 19th Edition, 2015, p. 537-544.

[3] GBD 2019 Colorectal Cancer Collaborators, Global, regional and national burden of colorectal cancer and its risk factors, 1990-2019: a systematic analysis for the Global Burden of Disease study 2019, Lancet Gastroenterol Hepatol, 2022, 7(7):627-647.

[4] American Cancer Society, Colorectal cancer facts and figures 2020-2022. 2020

[5] Stein DE, Lisle DM, Kumar PP, Nowak-Choi KA, BMJ Best Practice, 25 Nov 2022,

https://bestpractice.bmj.com/topics/en-gb/258?q=Colorectal%20cancer&c=suggested. Last accessed 8 Dec 2022.

[6] Public Health England, Bowel cancer screening: programme overview, 17 Mar 2021, https://www.gov.uk/guidance/bowel-cancer-screening-programme-overview. Last accessed 8 Dec 2022.

[7] Cairns SR, Scholefield JH, Steele RJ, et al, British Society of Gastroenterology and Association of Coloproctology for Great Britain and Ireland, Guidelines for colorectal cancer screening and surveillance in moderate and high risk groups (update from 2002), Gut, 2010, 59(5): 666-689

[8] Referral to a specialist, Cancer Research UK, 6 Dec 2021, https://www.cancerresearchuk.org/about-cancer/bowel-cancer/getting-diagnosed/referral-specialist. Last accessed 8 Dec 2022.

[9] National Institute for Health and Care Excellence, Molecular testing strategies for Lynch syndrome in people with colorectal cancer, 22 Feb 2017.

Authors: Ross Tulloch, Thitikorn Nuamek