Q: My friend was just diagnosed with colon cancer, and they said it’s stage IIIB. What does that mean? How do doctors figure out the stage?
A: When someone is diagnosed with colon cancer, one of the first things we do is figure out the stage. That just means we’re trying to understand how far the cancer has grown and whether it has spread. Staging helps guide treatment and gives us an idea of what to expect moving forward.
Doctors use something called the TNM system, which looks at three main things: how deep the tumor goes into the colon wall (T), whether any nearby lymph nodes are involved (N) and whether the cancer has spread to other parts of the body or metastasis (M). From that, we group the cancer into stages from 0 to IV, with some stages having subcategories for more detail.
To simplify what each stage means for treatment:
— Stage 1: removal with colonoscopy or surgery
— Stage 2: surgery
— Stage 3: surgery and chemotherapy
–Stage 4: chemotherapy and surgery
This is for colon cancer. Other types of cancer have different TNM staging because they have different treatments. The stage is set when the patient is first diagnosed, not after receiving any treatment. So even if the tumor shrinks or disappears, the original stage never changes.
Hearing those numbers and letters can feel overwhelming, but they help us make the best plan. And remember, colon cancer is often very treatable, especially when it’s caught early. If you or someone you care about is facing a diagnosis, don’t be afraid to ask questions. Your care team is there to help you understand every step of the way.
Dr. Shauna Lorenzo-Rivero is the founder of the Greater Chattanooga Colon Cancer Foundation and is a member of the Chattanooga-Hamilton County Medical Society.