Colon cancer stages
Medical review by Mayo Clinic Staff
Updated: September 10, 2026
If you’re diagnosed with colon cancer, you might need more tests to find out how far the cancer has spread. These test results tell you the stage of your cancer. When you know the stage of your cancer, it helps you and your healthcare team create the most effective treatment plan for you.
Advancements in treatment have significantly improved survival rates and quality of life for people with all stages of colon cancer. Each person’s experience with colon cancer is unique. A supportive healthcare team can help you have unique options every step of the way.
In some cases, imaging tests of the belly, pelvis and chest may help you understand your cancer stage. These tests create pictures that show the size and location of your cancer. Often, imaging isn’t enough. You may need surgery to find out the stage of your cancer.
Understanding colon cancer staging
Your colon cancer stage affects much of your treatment plan. But the words used to describe cancer and treatments can be very detailed and complicated. It’s important to ask questions and work with your healthcare team to understand your stage and what it means for your colon cancer diagnosis. That's why we offer comprehensive consultations with plenty of time for discussion.
There are five stages of colon cancer: 0, 1, 2, 3 and 4. There is no stage 5 colon cancer. The lower numbers refer to cancer that is in the colon only and has not spread. Higher numbers mean more-advanced cancer. Stage 4 colon cancer is considered the most advanced and has spread to distant areas of the body.
Healthcare professionals commonly use the TNM system to discuss staging. TNM stands for tumor, nodes and metastasis. The system looks at three key factors:
- T. How deeply the main tumor has penetrated into the wall of colon.
- N. Whether it has spread to nearby lymph nodes.
- M. Whether the cancer has spread to other parts of the body, called metastasis.
There are five stages of colon cancer, ranging from stage 0, where cancer cells are confined to the inner lining of the colon, to stage 4, where cancer has spread to distant organs.
Mayo Clinic teams are highly experienced in diagnosing and staging colon cancer.
We diagnose and stage colon cancer of all types and stages daily. This experience helps our teams accurately define each person’s cancer and identify appropriate treatment options at every stage. Understanding the stage is a critical step in planning care and setting expectations.
Stage 0 colon cancer
Stage 0 colon cancer is the earliest stage, where cancer cells are only in the innermost layer of the colon. At this stage, the cancer hasn't spread beyond this inner lining. You may hear it called carcinoma in situ.
In stage 0 colon cancer, the earliest stage, cancer cells are only present in the inner lining of the colon.
If you have stage 0 colon cancer, polyp removal may be the only treatment you need. The goal is to remove cancer cells completely. At this stage, cancerous polyps can be removed with a tool during your colonoscopy. This is known as a polypectomy. If your cancer is too big, you may need to have part of your colon removed in a procedure called a partial colectomy.
Stage 1 colon cancer
Stage 1 colon cancer has grown into the deeper layers of the colon. However, the cancer remains in the colon and has not spread to nearby lymph nodes or other parts of the body. If your cancer hasn't spread, it's considered localized.
In stage 1 colon cancer, the cancer has grown into the inner layers of the colon wall but has not spread to nearby lymph nodes or distant sites.
As in stage 0 colon cancer, removing cancerous polyps with a polypectomy may be the only treatment you need for stage 1 colon cancer. If the cancer cells are the type to grow and spread quickly, called high grade, more of the surrounding healthy tissue may be taken to ensure all the cancer cells are removed. If your cancer was not in a polyp, you may need a partial colectomy to remove the cancerous section of the colon. Nearby lymph nodes also may be removed to help control or prevent cancer spread.
Stage 2 colon cancer
Stage 2 colon cancer has spread into the outermost layers of the colon and possibly nearby tissues or organs. However, it has not spread to any lymph nodes. If your stage 2 cancer remains in the colon, it is considered localized. If it has spread to nearby organs, it’s considered regional.
- Stage 2A. Cancer has reached the outer layers of the colon but has not grown through them. It has not spread to nearby lymph nodes or distant sites.
- Stage 2B. Cancer has grown through the outer wall of the colon. It has not spread to nearby lymph nodes or distant sites.
- Stage 2C. Cancer has grown through the colon wall and has reached nearby organs or tissues. It has not spread to nearby lymph nodes or distant sites.
In stage 2 colon cancer, the cancer has grown through the wall of the colon and may invade nearby tissues, but it has not spread to the lymph nodes or distant organs.
Surgery to remove the affected section of the colon, called a partial colectomy, may be the only treatment needed. Nearby lymph nodes also may be removed during this procedure. Depending on the extent and type of cancer, chemotherapy may be recommended before or after surgery.
Chemotherapy given after surgery is called adjuvant chemotherapy. It can help reduce your risk of recurrence.
At Mayo Clinic, early research helped establish adjuvant chemotherapy as part of colon cancer care.
Mayo Clinic was among the first medical centers to use adjuvant chemotherapy for colon cancer — treatment given after surgery to lower the risk that cancer returns. Early research from our teams helped shape how this approach is used today, supporting decisions about when chemotherapy may benefit people with stage 2 disease.
Stage 3 colon cancer
Stage 3 colon cancer has spread into nearby lymph nodes but not to distant sites in the body. Stage 3 colon cancer is known as regional cancer.
- Stage 3A. Cancer has grown through the innermost layers of the colon and possibly the muscle layer. It also has affected a few nearby lymph nodes but not distant sites.
- Stage 3B. The cancer has reached the outermost muscle layer of the colon and possibly the colon wall. It may have reached tissues lining nearby organs or structures. It also has affected a few nearby lymph nodes but not distant sites.
- Stage 3C. The cancer has spread through the outermost layer of the colon and possibly the colon wall. It may have reached the lining of the abdominal cavity. This lining is called the peritoneum. It also has affected a few nearby lymph nodes but not distant sites.
In stage 3 colon cancer, the cancer has spread to nearby lymph nodes but not to distant organs.
If you have stage 3 colon cancer, you likely will need surgery to remove the affected section of the colon, called a partial colectomy. Affected lymph nodes also may be removed. If your cancer cannot be completely removed with surgery, you also may need chemotherapy.
If you have advanced cancer that can’t be removed completely with surgery, you may need chemotherapy or immunotherapy to shrink the cancer first. This way, the cancer can be more easily removed later with surgery. Radiation also may be recommended if your cancer has grown into a nearby organ or if cancer cells are still present after surgery.
Mayo Clinic’s multidisciplinary approach reduces barriers and improves coordination.
Our colon cancer teams include surgeons, medical oncologists, gastroenterologists, and other specialists as needed. These experts work together to coordinate care and align treatment decisions when surgery, chemotherapy, or other therapies are part of the plan. This team‑based approach helps people move through complex treatment with greater clarity and continuity.
Stage 4 colon cancer
Stage 4 colon cancer has spread to distant parts of the body, or parts of the body not close to the colon. If you have stage 4 colon cancer, it is called metastatic or distant colon cancer.
- Stage 4A. Cancer has spread to one distant organ or distant set of lymph nodes.
- Stage 4B. Cancer has spread to more than one distant organ or distant set of lymph nodes.
- Stage 4C. Cancer has spread to distant parts of the peritoneum.
In stage 4 colon cancer, cancer has spread beyond the colon and nearby lymph nodes to distant organs, most commonly the liver.
If you have stage 4 colon cancer, you may need surgery to remove the cancer from affected organs. Chemotherapy or targeted therapy may be used to control your cancer, and it can be used to reduce the cancer enough to make surgery an option. Immunotherapy may be recommended if your cancer cells have specific genetic changes. Radiation also can relieve symptoms or temporarily shrink your cancer.
Depending on your situation, you may be eligible to take part in a clinical trial. Ask your healthcare team if there are available options for your type of cancer. Clinical trials are available at different points on the cancer journey and don’t have to be a last resort.
How fast does cancer spread?
When you’re diagnosed with colon cancer, it may feel like you need to have your cancer removed as soon as possible. And while cancer removal is typically the first step in your treatment plan, you need to understand the details of your diagnosis so you can make decisions with confidence.
Colon polyps can take a long time to grow before becoming cancerous, often 10 to 15 years. Though not all polyps turn into cancer, certain types, such as adenomas, have a higher risk of becoming cancer.
Once they become cancerous, their growth will vary depending on many factors, including the type of cancer cells, your age and your overall health. Be sure to ask your healthcare team about the factors that affect your cancer’s growth.
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Mayo Clinic’s approach to colon cancer staging
Colon cancer treatment can be different based on the stage and location of your cancer. It's important to have a clear and detailed diagnosis so you can feel confident in your treatment plan. Here at Mayo Clinic, our colon cancer team aims for personalized treatment plans — or plans that are based on your cancer, your health, and your goals for treatment and recovery.
And it all starts with a strong foundation of the right diagnosis. With advanced testing and a deep understanding of colon cancer, the expert team at Mayo Clinic is here to help you understand your cancer and its stage. This can help you make decisions with confidence.
You can also contact our helpful scheduling teams by calling:
