Colon cancer almost always begins as an adenomatous polyp, which is a collection of noncancerous (benign) cells in the lining of the colon. With that said, the vast majority of polyps are harmless. Experts estimate that only 5-10% of colon polyps will eventually progress and become cancerous (malignant). This gradual process typically takes place over 10 to 15 years, often after age 50. Once colon cancer develops, it tends to grow slowly, although several factors can influence its rate of progression, such as the cellular makeup of the tumor and the age and overall health of the patient.

When detected early, colon cancer is highly treatable. However, early-stage colon cancer is usually “silent,” making early detection a challenge. Even so, many colon cancers can be prevented through routine screening. During a colonoscopy—the current gold standard in colon cancer screening—a physician can identify and remove precancerous polyps as well as early-stage cancerous polyps. For these reasons, most physicians encourage average-risk individuals to have a colonoscopy every 10 years beginning around age 45.

How are colon cancer stages determined?

Colon cancer stages are determined based on four specific factors:

The size of the tumor
Whether cancer is found in nearby lymph nodes
Whether the tumor has spread to surrounding tissues
The appearance of the cancer cells when viewed under a microscope

These factors are evaluated separately, and the individual assessments are combined into a single score. Colon cancer stages range from 0 to 4, with lower numbers indicating less invasive cancers.

stages of colon cancer

Stage 0 colon cancer

Also known as carcinoma in situ or intramucosal carcinoma, stage 0 colon cancer refers to cancerous cells that are confined to the innermost layer of the colon lining (mucosa) and have not invaded deeper layers of the colon wall, spread to nearby lymph nodes or metastasized to distant organs. At this early stage, the cancer is usually detected during a routine screening test, such as a colonoscopy or sigmoidoscopy, and it is considered highly treatable.

Treatment for stage 0 colon cancer often involves surgical removal of the cancerous tissue, which may be curative. Regular surveillance and follow-up care are typically recommended to monitor for any signs of recurrence.

Stage 1 colon cancer

Stage 1 colon cancer is characterized by the presence of cancerous cells that have invaded the inner layers of the colon wall but have not spread beyond the wall or into nearby lymph nodes or distant organs. At this early stage, the tumor is usually small, localized and highly treatable.

Treatment for stage 1 colon cancer usually involves surgical removal of the tumor and a slim margin of surrounding healthy tissue, which may be curative. Depending on the characteristics of the tumor and other factors, additional treatments such as chemotherapy or targeted therapy may be considered to reduce the risk of recurrence.

Stage 2 colon cancer

Stage 2 colon cancer is characterized by cancerous cells that have spread beyond the inner layers of the colon wall into the surrounding tissue but have not invaded nearby lymph nodes or distant organs. At this stage, the tumor is considered locally advanced, but it is still confined to the colon.

Treatment for stage 2 colon cancer typically involves surgical removal of the tumor and some surrounding healthy tissue, which may be curative. Depending on the type of tumor and other factors, additional treatments such as chemotherapy may be recommended to reduce the risk of recurrence. While the prognosis for stage 2 colon cancer is generally favorable, regular surveillance and follow-up care are important to monitor for any signs of recurrence.

Stage 3 colon cancer

Stage 3 colon cancer is characterized by cancerous cells that have spread beyond the colon wall and into nearby lymph nodes but have not metastasized to distant organs. At this stage, the cancer is considered locally advanced.

The precise treatment approach for stage 3 colon cancer can vary depending on the size of the tumor, the extent of lymph node involvement and other factors. Typically, it involves surgical removal of the tumor and some nearby lymph nodes followed by chemotherapy to target any remaining cancer cells and reduce the risk of recurrence. Regular surveillance and follow-up care are essential to monitor for signs of cancer progression or recurrence.

Stage 4 colon cancer

Also known as metastatic colon cancer, stage 4 colon cancer is characterized by cancerous cells that have metastasized from the colon to distant organs or tissues. At this advanced stage, treatment focuses on managing symptoms, controlling cancer spread and enhancing quality of life.

Depending on the extent and location of cancer metastases, treatment options for stage 4 colon cancer may include surgery, chemotherapy, targeted therapy, immunotherapy and/or radiation therapy. Supportive care is also an important aspect of managing stage 4 colon cancer.

What is metastatic colon cancer?

Both metastatic colon cancer and stage 4 colon cancer refer to an advanced-stage tumor that developed in the colon and metastasized to distant organs or tissues. After entering the bloodstream or lymphatic system, colon cancer cells can potentially spread to any area of the body. However, the most common metastasis sites are the lungs, liver, brain, abdominal cavity lining (peritoneum) and distant lymph nodes.

Although early-stage colon cancer does not usually cause noticeable symptoms, more advanced colon cancer may cause:

Changes in bowel habits
Overwhelming fatigue
Unexplained weight loss

Metastatic colon cancer can also cause symptoms in the affected area of the body, such as the:

Lungs – Chronic coughing, difficulty breathing, shortness of breath and chest pain
Liver – Jaundice, swelling in the arms and legs, abdominal bloating and nausea
Brain – Headaches, confusion, memory loss and blurred vision
Lymph nodes in the abdominal cavity – Loss of appetite and abdominal bloating
Peritoneum – Abdominal pain, bloating, a persistent feeling of fullness, unexpected weight gain and nausea

Benefit from world-class care at Moffitt Cancer Center

If you would like additional information about colon cancer stages, you can request an appointment with a specialist in Moffitt’s renowned Gastrointestinal Oncology Program by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.

Diagnosis