Last reviewed: 7 Feb 2021
Last updated: 11 Mar 2020



History and exam

Key diagnostic factors

  • increasing age
  • rectal bleeding
  • change in bowel habit
  • rectal mass
  • positive family history
  • abdominal mass

Other diagnostic factors

  • anemia
  • male sex
  • abdominal pain
  • weight loss and anorexia
  • abdominal distension
  • palpable lymph nodes

Risk factors

  • increasing age
  • adenomatous polyposis coli mutation
  • Lynch syndrome (hereditary nonpolyposis colorectal cancer)
  • MYH-associated polyposis
  • hamartomatous polyposis syndromes
  • inflammatory bowel disease
  • obesity
  • acromegaly
  • limited physical activity
  • lack of dietary fiber

Diagnostic investigations

1st investigations to order

  • CBC
  • liver biochemistry
  • renal function
  • colonoscopy
  • double-contrast barium enema
  • CT colonography
  • CT scan of thorax, abdomen, and pelvis

Investigations to consider

  • pelvic MRI
  • transrectal endoscopic ultrasound (TRUS)
  • biopsy
  • carcinoembryonic antigen (CEA)
  • PET scan

Emerging tests

  • advanced optical imaging techniques

Treatment algorithm


Associate Dean Clinical Operations


Department of Surgery

Drexel University College of Medicine




DES declares that he has no competing interests.


Division of Colorectal Surgery

Department of Surgery

Drexel University




JLP declares that he has no competing interests.

Assistant Professor of Medicine

Department of Surgery

Drexel University




JR declares that he has no competing interests.

Dr David E. Stein, Dr Juan L. Poggio, and Dr Jascha Rubin would like to gratefully acknowledge Dr Najjia Mahmoud, Dr Emily Carter Paulson, Dr Gary Atkin, Dr Anne Ballinger, Dr Mark O'Hara, Dr Mark Harrison, and Dr Robert Glynne-Jones, previous contributors to this topic.


NM, ECP, MOH, GA, and AB declare that they have no competing interests. MH is the chair of the Mount Vernon Upper GI Tumour Site Specific Group and a member of the National Cancer Research Institute anal, rectal, and advanced colorectal groups. He has also received honoraria for speaking and has been supported to attend international meetings in GI cancer from Roche. He has also received research funding from Pfizer for a trial in rectal cancer. RGJ is the chief medical adviser to the charity Bowel Cancer UK. He has received honoraria for lectures from Roche, Sanofi, and Pfizer. He has received funding for the EXTRA study, involving capecitabine and radiotherapy in anal cancer, published in the International Journal of Radiation Biology Physics. RGJ has also received funding and free cetuximab for an ongoing phase I/II study integrating cetuximab into chemoradiation in rectal cancer, and has an agreement from Roche to supply bevacizumab for 3 months to 60 patients in one randomised phase II study as neoadjuvant chemotherapy in rectal cancer (BACCHUS). He has also been supported by Roche to attend international meetings in GI cancer.

Peer reviewersVIEW ALL

Consultant Colorectal Surgeon

St Mark's Hospital and Academic Institute

Northwick Park




SC declares that she has no competing interests.

Chief of Staff


Department of Colorectal Surgery

Cleveland Clinic




SW declares that he has no competing interests.

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