Sue Chang, MD, FCAP, is an Assistant Clinical Professor in the Department of Pathology at City of Hope National Medical Center in Duarte, CA.

Not sure what your cancer stage is or what it means? Now’s a great time to get informed, as even your health care team is learning new things about cancer staging. The American Joint Committee on Cancer (AJCC) recently released the latest edition of its cancer staging manual with new and updated staging for many types of cancer. Most cancer treatment centers started using the updated manual on January 1, 2018.

Staging is a key component in the development of your treatment plan. The extent of cancer at the time of diagnosis—where it’s located, if or where it has spread, and whether it’s affecting the other parts of the body—is commonly referred to as the "stage" of cancer.

The cancer staging process is multifaceted. Doctors work together to gather the many pieces of information that go into determining a cancer’s stage. Findings from procedures and tests such as physical examinations, imaging scans, biopsies, blood tests, and genetic testing are used to assign the stage. The stage is the most accurate snapshot of the cancer at that point in time.

Yet nearly half of patients treated for cancer in the past 2 years don’t know the stage of their cancer, according to a recent study done at a Pennsylvania cancer center. Here are 5 reasons why it's important for you and your support network of friends and family to ask about and understand your cancer stage.

1. Your cancer stage determines your treatment.

The treatment plan that is best for you depends on the type and stage of cancer. Many treatment guidelines and timelines are based on the specific cancer stage. The order in which treatments, such as chemotherapy, radiation therapy, or surgery, are given can also depend on the stage.

2. Your cancer stage helps predict your chance of recovery.

Even though each person is different and each cancer experience is unique, some generalizations can be made across cancer types and stages. Cancer staging is a way to group cases together and predict the likelihood of remission, which means no signs of cancer in the body, and survival. It can also help predict if the cancer will grow, spread, or come back after treatment, called a recurrence.

3. Your cancer stage sets expectations and starts discussions.

“Cancer” is a scary word, but not all cancers and cancer stages are the same. Knowing your cancer stage is a way to better predict and prepare for the challenges ahead. A cancer stage is like a roadmap based on the footsteps of previous patients with cancer at a similar stage.

4. Your cancer stage can help identify clinical trials that may be right for you.

There are “eligibility criteria” to meet before patients can join a clinical trial. That criteria often includes a particular cancer stage. Staging gives researchers a way to bring together many patients across many treatment centers in order to make reasonable conclusions based on the results of the study.

5. Cancer staging changes as we learn more.

Cancer staging isn't an exact science. Doctors are learning more about it all the time. The newest version of the AJCC Cancer Staging Manual is the 8th one since 1959. Staging advances are built on knowledge gained from prior experience. That means your cancer stage might not be the same as the cancer stage of someone diagnosed 10 years ago. Therefore, your treatment options and chance of recovery may be different.

Our understanding of cancer is always growing. Cancer staging is one more tool to help us treat patients effectively. It’s important for all people with cancer to understand their staging so that they can be informed, active participants in their cancer care.

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