Making sense of cancer staging

When you or a loved one are diagnosed with cancer, all the terminology you hear can be confusing and just plain scary. So, let’s make at least one part of it easier to understand — cancer staging.

First things first, let’s put a definition with “cancer staging.” Staging is the process of determining how much cancer is in a person’s body, along with where it’s located. Those two factors together combine to help a physician determine the stage of cancer.

Why is staging important?

Well, once a person’s cancer is staged, the doctor then uses that information to help determine a path forward treatment-wise. The stage of cancer can also be used to determine whether a patient is likely to survive, otherwise known as prognosis.

“Determining the stage of a patient’s cancer is the first step in the treatment process,” says Sumana Nagireddy, MD, medical oncologist with Erlanger Oncology and Hematology. “Once we know the stage, we’re able to determine what treatment methods might work best based on the cancer stage and the patient’s individual health and needs.”

Let’s dive a little deeper into the topic of cancer staging.

How is cancer staging determined?

Cancer staging is a part of the diagnosis process. To determine a diagnosis, a doctor will use a variety of tools, including imaging scans, lab tests and a physical exam.

To determine the extent of cancer, the doctor will look at the primary tumor to analyze its size, location and whether it has spread. He or she will also look more broadly at the body to determine whether there are other tumors. Lymph nodes are also often examined to see if cancer has spread to them.

Beyond the initial imaging scans and lab tests, biopsies are often used to confirm diagnosis and fully understand the scope of the cancer.

Are there different kinds of cancer staging?

Yes, actually. There are two main types of staging — clinical and pathologic.

Clinical staging is based on a physical exam, imaging tests and biopsies, the tools we’d described above. This type of staging provides the baseline used to see how a person’s cancer is responding to treatment.

Pathologic staging occurs when surgery is part of the treatment plan. This type of staging uses all the tools we’ve talked about previously, but combines those results with information learned during a surgical procedure.

There are a couple other types of cancer staging, which may be used depending on the type of cancer a person has and the treatment he or she undergoes. Post-therapy staging looks at how much cancer remains after a person is treated with chemotherapy, hormone therapy and/or radiation therapy, while restaging determines the extent of cancer if it returns after treatment.

How does cancer staging work?

There are different methods of staging, but cancer staging primarily looks at the location of the tumor, the size and extent of the tumor, whether there is lymph node involvement, and whether the cancer has metastasized, or spread from the original location.

The TNM Staging System is the most commonly used cancer staging system, established by the American Joint Committee on Cancer and the International Union for Cancer Control. It’s used to stage many cancers, though some, like certain cancers of the blood and Hodgkin lymphoma, do not use this system.

Under the TNM system, a doctor “grades” or “rates” a person’s cancer in three areas:

  • Tumor — evaluates the primary tumor
  • Nodes — determines whether the cancer has spread to nearby lymph nodes
  • Metastasis — determines whether the cancer has spread to other areas of the body

Once the T-N-M categories are evaluated, they’re put together into what’s known as “stage grouping.” These stages are likely what you’re familiar with, as they categorize cancer from 0 to IV.

  • Stage 0 means that abnormal cells are present but haven’t spread. This stage is also referenced as “carcinoma in situ,” which is not cancer but may become cancer.
  • Stage I–Stage III indicate that cancer is present. The higher the number, the larger the tumor and the more it has spread into nearby tissues.
  • Stage IV indicates that cancer has spread to other areas of the body.

What to make of cancer staging

Ultimately, cancer staging isn’t something to fear — it provides doctors with a way to categorize your cancer and determine the best path forward.

Knowing the full extent of the disease is the first step in working to overcome it. Use this information and other details provided by your doctor to help you stay in the know about your diagnosis and treatment options.

Dr. Nagireddy and a full team of clinicians offer exceptional oncology care through Erlanger Oncology and Hematology. If you or a loved one have been diagnosed with cancer, Erlanger provides the expertise of academic oncology services located right here in your hometown.