From Stage 0 to Stage 4: Understanding The Stages of Colorectal Cancer

Staging Colorectal Cancer: Learning About The Spread - DoctorOnCall

Colorectal cancer staging is a way to classify the extent of colorectal cancer based on the size and location of the tumour, as well as whether it has spread to other organs or tissues. Staging helps doctors determine how best to treat each patient’s cancer.

Defining Colon and Rectal Cancers

Colon and rectal cancers are a part of colorectal cancer that affects the large intestine, which is located at the end of the digestive system. Colon cancer usually begins as polyps, which are growths on the inner lining of the colon or rectum that can become cancerous and even spread to nearby lymph nodes or other organs.

Stages of Colorectal Cancer

The TNM system, which assesses tumour growth and spread, is frequently used by doctors to describe the stage of colorectal cancer.

  • Tumour (T): Describes how deeply the primary tumour has grown into the bowel lining, with T1-T4a indicating increasing depth.

  • Node (N): Indicates if cancer has spread to lymph nodes, with N0-N2b indicating increasing spread.

  • Metastasis (M): Describes if cancer has spread to other parts of the body, with M0-M1c indicating increasing spread.

This system assigns a number to each stage based on how large the tumour is and how far the cancer has spread. There are five stages, from the earliest stage to stage IV:

  • Stage 0: Cancer cells are restricted to the inner lining of the colon or rectum.

  • Stage I: The cancer has penetrated the muscle layer but has not yet spread to the lymph nodes or nearby tissue.

  • Stage II: The cancer has spread through the wall but not to nearby tissue or lymph nodes.

  • Stage III: The cancer has not spread to other organs but has reached nearby tissues or one to three lymph nodes.

  • Stage IV: The cancer has spread to more than one part of the body.

  • Recurrent cancer: Cancer that has come back after treatment and can be found in the colon, rectum, or other parts of the body.

How Do I Diagnose Colon Cancer?

Medical practitioners can perform a wide range of diagnostic tests for colon cancer. This test includes:

  • CT scans or MRIs: Create detailed images of the body that can show if the colon cancer cells have spread to other organs.

  • Colonoscopy: Views the inside of the colon and rectum to look for polyps or tumours.

  • Faecal Immunochemical Test (FIT): Tests for traces of blood in your stool, which may be an indication of cancer.

  • Tumour marker tests: Measures levels of certain proteins in the blood, which may indicate colorectal cancer activity.

  • Biopsy: Removes a small sample of tissue from the colon or rectum to examine it for signs of cancer.

Colon Cancer Treatment

Treatment options for colon cancer vary depending on the stage of the cancer and whether it has spread to other parts of the body.

Stage 0 colon cancer, for example, may be treated with localised surgery, whereas more advanced stages, such as stage III colon cancer, may require chemotherapy or radiation therapy in addition to surgery.

Doctors will consider a variety of factors for the patient when developing colon cancer, such as age and overall health, to determine the best treatment method for each individual case.

Conclusion

Colon cancer is one of the most common types of cancer, but it can be successfully managed with early detection and proper treatment. Colorectal cancer is staged to determine its severity based on the size, location, and presence of metastases to other organs or tissues. 


Those diagnosed with colon cancer have access to a variety of diagnostic tests and treatment options, allowing for individualised care. You can reduce your risk of complications and ensure a successful treatment outcome if you detect the disease early.

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