Colon Cancer Staging

Staging Colon Cancer 

The growth and spread of malignant colon polyps is assessed through a process called staging. A tumor growing in the large intestines may produce changes in bowel habits or your overall sense of well being. (see Colon Cancer Symptoms).

However, symptoms do not tell us where the cancer is or to what extent it has spread. Tests like a colonoscopoy or a sigmoidoscopy may be used to look for tumors within the colon and a biopsy may be used to rate the tumor.

The staging process is a standardized method for describing the spread and growth of the cancer and provides a basis for determining viable treatment options. This also an opportunity for you and your doctors to discuss your personal preferences and needs.

Colon cancer staging begins by evaluating three key components of cancer: size, location and spread. In the earliest stages of colon cancer (stage 0), the cancer has not spread and tumors are localized to the inner layer (mucosa) of the colon. Later stages are characterized by the growth and spread of cancerous tissues into the layers of the colon wall. The cancer has typically grown through the colon wall and spread into nearby tissues in the most advanced stages (stage IV).

Understanding the TNM System

The American Joint Committee on Cancer's (AJCC) TNM system, now the most widely accepted method for evaluating colon cancer, uses a stage grouping of three key components; T, N and M:

• Tumor - The tumors are rated on a scale 0-4 where T0 indicates no evidence of the primary tumor expanding into local tissue, and the increasing numbers (T1-T4) describe the extent and spread of tumor into and through the colon wall. Carcinoma in situ, Tis, describes an early cancer that has not gone beyond to the inner muscle layer (the mucosa).
• Node - If cancer is found in the lymph nodes, the quantity of cancer cells found is rated using N1 or N2. Conditions where the cancer has not spread to the lymph nodes is indicated by N0.
• Metastasized - Cancer that has spread (metastasized) is indicated by M1. Otherwise, M0 is used if there are no signs of metastases.

Each category (T, N and M) is assessed and rated. An X is used to denote insufficient information (the condition of the particular factor cannot be adequately assessed).

Colon Cancer Stage Grouping

The TNM system assesses the size of the tumor and how far the cancer has spread from the point of origin:

• Stage 0 Colon Cancer:  The cancer has not grown beyond the mucosa (inner muscle). (Example: Tis, N0, M0)
• Stage I Colon Cancer:  The cancer has grown beyond the mucosa (inner muscle) but has not spread beyond the colon to other sites or lymph nodes. (Example: T1, N0, M0 or T2, N0, M0)
• Stage II Colon Cancer:  The cancer has grown into or through the colon wall. At this stage, it may or may not have reached nearby organs. There is no evidence of spread to lymph nodes or distant sites.  (Example: T3, N0, M0)
• Stage III Colon Cancer:  The cancer has metastasized and spread to nearby lymph nodes. The tumor may be any size (T1-T4). The cancer may or may not have reached nearby organs. Distant sites, like the lung or liver, remain unaffected. (Example: T1, N1, M0)
• Stage IV Colon Cancer:  The cancer may be any size and has spread throughout the body to distant sites like the liver, lung, or lining of the abdominal cavity. (Example: Any T, Any N, M1)

Understanding Colon Cancer Staging

The care team at Cancer Treatment Centers of America (CTCA) understands that this may be a very emotional time. The staging process provides a lot of valuable information for you and your doctors; and we are here every step of the way to answer your questions and support you through this process.

There may be a lot of new information to consider and the CTCA care team is dedicated to ensuring that you clearly understand the process and the variety of treatment options available to you. With knowledge, expertise and compassion, our cancer experts clearly communicate the information you need to know.

Taking the Next Steps

When you're ready to learn more, call 800-615-3055 or Chat Now to talk with a CTCA Oncology Information Specialists. Our representatives are available 24 hours a day, every day of the week. We're ready to help, at any stage.

Next Topic: Colon Cancer Treatments