Find out what a survival rate can tell you and what it can't. This can help you put survival statistics in perspective.

By Mayo Clinic Staff

When first diagnosed with cancer, many people ask about their prognosis. You might want to know whether your cancer is relatively easy or more difficult to cure. Your doctor can't predict the future, but can make an estimate based on other people's experiences with the same cancer.

It's up to you whether you want to know the survival rates related to your cancer. The numbers can be confusing and frightening.

Cancer survival rates or survival statistics tell you the percentage of people who survive a certain type of cancer for a specific amount of time. Cancer statistics often use an overall five-year survival rate.

For instance, the overall five-year survival rate for bladder cancer is 78 percent. That means that of all people who have bladder cancer, 78 of every 100 are living five years after diagnosis. Conversely, 22 out of every 100 are dead within five years of a bladder cancer diagnosis.

Cancer survival rates are based on research from information gathered on hundreds or thousands of people with a specific cancer. An overall survival rate includes people of all ages and health conditions who have been diagnosed with your cancer, including those diagnosed very early and those diagnosed very late.

Your doctor may be able to give you more specific statistics based on your stage of cancer. For instance, 52 percent, or about half, of people diagnosed with early-stage lung cancer live for at least five years after diagnosis. The five-year survival rate for people diagnosed with late-stage lung cancer that has spread (metastasized) to other areas of the body is 4 percent.

Overall survival rates don't specify whether cancer survivors are still undergoing treatment at five years or if they've become cancer-free (achieved remission). Other types of survival rates that give more specific information include:

  • Disease-free survival rate. This is the number of people with cancer who achieve remission. That means they no longer have signs of cancer in their bodies.
  • Progression-free survival rate. This is the number of people who still have cancer, but their disease isn't progressing. This includes people who may have had some success with treatment, but the cancer hasn't disappeared completely.

Cancer survival rates often use a five-year survival rate. That doesn't mean cancer can't recur beyond five years. Certain cancers can recur many years after first being found and treated. For some cancers, if it has not recurred by five years after initial diagnosis, the chance of a later recurrence is very small. Discuss your risk of a cancer recurrence with your doctor.

You and your doctor might use survival statistics to:

  • Understand your prognosis. The experience of other people in your same situation can give you and your doctor an idea of your prognosis — the chance your cancer will be cured. Other factors include age and general health. Your doctor uses these factors to help you understand the seriousness of your condition.
  • Develop a treatment plan. Statistics can also show how people with your same cancer type and stage respond to treatment. You can use this information, along with your goals for treatment, to weigh the pros and cons of each treatment option.

    For instance, if two treatments give you similar chances for remission, but one has more side effects, you might choose the option with fewer side effects.

    In another example, a treatment may offer a chance for a cure, but only for 1or 2 people out of every 100. For some, these chances are promising enough to put up with side effects. For others, the chance for a cure isn't worth the treatment's side effects.

    Your doctor can help you understand the benefits and risks of each treatment.

Cancer survival statistics can be frustrating. The survival rate for people with your particular cancer might be based on thousands of people. So while cancer survival rates can give a general idea about most people in your situation, they can't give your individual chances for cure or remission. For that reason, some people ignore cancer survival rate statistics.

Survival statistics don't take into account other medical conditions you have. If your health is otherwise perfect, you're likely to have a greater chance of survival than the statistics suggest.

If you have other very significant medical conditions, you may not have the chance of survival suggested by the statistics. Your doctor may be able to help adjust the statistics for your specific situation.

Survival rates have other limitations. For instance, they can't:

  • Give you information about the latest treatments. People included in the latest cancer statistics were diagnosed more than five years ago. The effects of any recent treatment discoveries won't affect survival statistics for at least five years.
  • Tell you what treatments to choose. That's up to you and your doctor. For some people, the treatment with the greatest chance for remission is the one they'll choose. But many people take other factors, such as side effects, cost and the treatment schedule, into their decision.

Survival rates are usually given in percentages. For example, the five-year survival rate for non-Hodgkin's lymphoma is 68 percent.

You might find that it's easier to understand the numbers in terms of people. For the non-Hodgkin’s lymphoma example, the survival rate can be stated like this: For every 100 people diagnosed with non-Hodgkin's lymphoma, 68 survive for at least five years after diagnosis. Conversely, 32 people die within five years of a non-Hodgkin's lymphoma diagnosis.

If your doctor talks about statistics and you don't understand, ask for an explanation that makes sense. Ask questions if you need more information.

It's up to you and your doctor to interpret the numbers. You might think a 68 percent survival rate is positive, or it may frighten you as you think about your future. Your doctor can help you put the statistics in perspective and understand your individual situation.

It's up to you whether you want to know the survival rates associated with your type and stage of cancer. Because survival rates can't tell you about your situation, you might find the statistics impersonal and not helpful. But some people want to know everything they can about their cancer. For that reason, you might choose to know all the pertinent statistics.

The more you know about your type, grade and stage of cancer, the more closely you can predict your risk. If you have a localized cancer and you are using statistics that include many people with a more widespread cancer, that data may not apply to you.

Knowing more about your cancer can reduce your anxiety as you analyze your options and begin your treatment, but survival statistics can be confusing and frightening. Tell your doctor if you'd prefer not to pay attention to the numbers. Some people prefer to know the "big picture," rather than detailed statistics. Let your doctor know how you prefer to receive the information. And if you have any questions or concerns about the statistics associated with your cancer, talk to your doctor.

April 15, 2014