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Colorectal cancer

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Last reviewed: 14 Apr 2025
Last updated: 24 Jan 2025

Summary

Definition

History and exam

Key diagnostic factors

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

Other diagnostic factors

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

Risk factors

  • increasing age
  • family history
  • adenomatous polyposis coli (APC) gene mutation
  • Lynch syndrome (hereditary nonpolyposis colorectal cancer)
  • MUTYH/MYH-associated polyposis
  • hamartomatous polyposis syndromes
  • inflammatory bowel disease
  • obesity
  • acromegaly
  • limited physical activity
  • lack of dietary fiber
  • smoking
  • moderate to heavy alcohol consumption
  • low vitamin D
  • consumption of red and processed meats
Full details

Diagnostic tests

1st tests to order

  • complete blood count
  • liver biochemistry
  • renal function
  • colonoscopy
  • CT colonography
  • CT scan of chest, abdomen, and pelvis
  • genetic testing
Full details

Tests to consider

  • MRI pelvis: rectal cancer protocol
  • transrectal endoscopic ultrasound
  • biopsy
  • carcinoembryonic antigen
  • PET scan
Full details

Emerging tests

  • advanced optical imaging techniques
  • blood-based tests
  • circulating tumor DNA

Treatment algorithm

ACUTE

rectal cancer, suitable for surgery

rectal cancer, not suitable for surgery

colon cancer, suitable for surgery

colon cancer, not suitable for surgery

Contributors

Authors

David E. Stein, MD, MHCM, FACS, FASCRS

Professor of Surgery

Georgetown University School of Medicine

Georgetown

DC

Regional Chief of Surgery

MedStar Health

Baltimore

MD

Disclosures

DES declares that he has no competing interests.

Kamila A. Nowak-Choi, MD

Assistant Professor

Department of Radiation Oncology

University of Maryland Upper Chesapeake Medical Center KCC Radiation Oncology

Bel Air

MD

Disclosures

KANC declares that she has no competing interests.

Acknowledgements

Dr David E. Stein and Dr Kamila A. Nowak-Choi would like to gratefully acknowledge Dr Pallavi P. Kumar, Dr David M. Lisle, Dr Juan L. Poggio, Dr Jascha Rubin, 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.

Disclosures

PPK, DML, JLP, JR, NM, ECP, MOH, GA, and AB declare that they have no competing interests. MH is the chair of the Mount Vernon Upper GI Tumor 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 on gastrointestinal 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 1/2 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 randomized phase 2 study as neoadjuvant chemotherapy in rectal cancer (BACCHUS). He has also been supported by Roche to attend international meetings in gastrointestinal cancer.

Peer reviewers

Susan Clark, BChir, MB

Consultant Colorectal Surgeon

St Mark's Hospital and Academic Institute

Northwick Park

Middlesex

UK

Disclosures

SC declares that she has no competing interests.

Steven Wexner, MD, FACS, FRCS, FRCS Ed, FASCRS, FAC

Chief of Staff

Chairman

Department of Colorectal Surgery

Cleveland Clinic

Weston

FL

Disclosures

SW declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: colorectal cancer screening [internet publication].Full text

National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: rectal cancer [internet publication].Full text

National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: colon cancer [internet publication].Full text

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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