Understanding Cancer Prognosis

Dr. Anthony Back talking with one of his patients

Oncologist Anthony L. Back, M.D., a national expert on doctor-patient communications, talks with one of his patients about what she'd like to know of her prognosis.

Credit: National Cancer Institute

If you have cancer, you may have questions about how serious your cancer is and your chances of survival. The estimate of how the disease will go for you is called prognosis. It can be hard to understand what prognosis means and also hard to talk about, even for doctors.

Factors That Can Affect Your Prognosis

Some of the factors that affect prognosis include:

  • the type of cancer and where it is in your body
  • the stage of the cancer, which refers to the size of the cancer and if it has spread to other parts of your body
  • the cancer’s grade, which refers to how abnormal the cancer cells look under a microscope and provides clues about how quickly the cancer is likely to grow and spread
  • certain traits of the cancer cells, such as certain genetic changes or hormone receptor status
  • your age and how healthy you were before cancer
  • how you respond to treatment

Learn more about Cancer Staging and Tumor Grade.

Seeking Information About Your Prognosis Is a Personal Decision

When you have cancer, you and your loved ones face many unknowns. Understanding your cancer and knowing what to expect can help you and your loved ones make decisions. Some of the decisions you may face include:

  • Which treatment is best for you?
  • If you want treatment?
  • How to best take care of yourself and manage treatment side effects?
  • How to deal with financial and legal matters?

Many people want to know their prognosis. They find it easier to cope when they know more about their cancer. You may ask your doctor about survival statistics or search for this information on your own. Or you may find statistics confusing and frightening, and think they are too impersonal to be of value to you. It is up to you to decide how much information you want.

If you do decide you want to know more, the doctor who knows the most about your situation is in the best position to discuss your prognosis and explain what the statistics may mean.

If you need help coping with your prognosis, you may find our information on Coping With Cancer helpful.

Understanding Statistics About Survival

Doctors estimate prognosis by using statistics that researchers have collected over many years about people with the same type of cancer. Several types of statistics may be used to estimate prognosis. The most commonly used statistics include:

  • Cancer-specific survival
    This is the percentage of people with a specific type and stage of cancer who have not died from their cancer during a certain period of time after diagnosis. The period of time may be 1 year, 2 years, 5 years, etc., with 5 years being the time period most often used. Cancer-specific survival is also called disease-specific survival. In most cases, cancer-specific survival is based on causes of death listed in medical records.
  • Relative survival
    This statistic is another method used to estimate cancer-specific survival that does not use information about the cause of death. It is the percentage of people with cancer who have survived for a certain period of time after diagnosis compared to people who do not have cancer.
  • Overall survival
    This is the percentage of people with a specific type and stage of cancer who have not died from any cause during a certain period of time after diagnosis.
  • Disease-free survival
    This statistic is the percentage of patients who have no signs of cancer during a certain period of time after treatment. Other names for this statistic are recurrence-free or progression-free survival.

Because statistics are based on large groups of people, they cannot be used to predict exactly what will happen to you. Everyone is different. Treatments and how people respond to treatment can differ greatly. Also, it takes years to see the benefit of new treatments and ways of finding cancer. So, the statistics your doctor uses to make a prognosis may not be based on treatments being used today.

Still, your doctor may tell you that you have a good prognosis if statistics suggest that your cancer is likely to respond well to treatment. Or they may tell you that you have a poor prognosis if the cancer is harder to control. Whatever your doctor tells you, keep in mind that a prognosis is an educated guess. Your doctor cannot be certain how it will go for you.

Where to Find Cancer Statistics

NCI collects and reports on cancer statistics through its SEER Program, which stands for Surveillance, Epidemiology, and End Results. From the Cancer Stat Facts page on the SEER web site, you can find answers to the most commonly asked questions about cancer statistics for many cancer types. You can also browse the latest SEER Cancer Statistics Review.

If You Decide Not to Have Treatment

If you decide not to have treatment, the doctor who knows your situation best is in the best position to discuss your prognosis.

Survival statistics most often come from studies that compare treatments with each other, rather than treatment with no treatment. So, it may not be easy for your doctor to give you an accurate prognosis.

Understanding the Difference Between Cure and Remission

Cure means that there are no traces of your cancer after treatment and the cancer will never come back.

Remission means that the signs and symptoms of your cancer are reduced. Remission can be partial or complete. In a complete remission, all signs and symptoms of cancer have disappeared.

If you remain in complete remission for 5 years or more, some doctors may say that you are cured. Still, some cancer cells can remain in your body for many years after treatment. These cells may cause the cancer to come back one day. For cancers that return, most do so within the first 5 years after treatment. But there is a chance that cancer will come back later. For this reason, doctors cannot say for sure that you are cured. The most they can say is that there are no signs of cancer at this time.

Because of the chance that cancer can come back, your doctor will monitor you for many years and do tests to look for signs of cancer’s return. They will also look for signs of late effects from the cancer treatments you received.

Cancer Prognosis Video Series

This video series explores three people with cancer and their doctor’s thoughts and feelings about prognosis. The videos explain key points about prognosis and how doctors and patients can talk about it in a clear and supportive way. Two viewer guides are also available: for patients (PDF-210KB) and for provider care teams (PDF-210KB).