Prostate cancer is the abnormal growth of cells in the prostate. Localized prostate cancer is cancer that hasn't spread outside the prostate.

Localized prostate cancer may be low-risk, medium-risk, or high-risk. Your test results will show your risk level and how likely it is that the cancer will grow. Men with low-risk localized prostate cancer and some men with medium-risk localized prostate cancer have the option of choosing active surveillance.

Unlike many other cancers, prostate cancer is usually slow-growing. For most men, this slow growth means they have time to learn all they can before they decide whether to have treatment or which treatment to have. The main treatment options for men who have localized prostate cancer are active surveillance, surgery, and radiation.

Most men who get prostate cancer don't die from it.

Active surveillance means that you will be watched closely by your doctor. You won't have further treatment unless the cancer starts to grow. If this happens, your doctor may recommend other treatment, such as surgery or radiation.

During active surveillance, your doctor will watch for any changes in the cancer. You will have frequent checkups and tests. These include PSA (prostate-specific antigen) tests, digital rectal exams, and prostate biopsies.

If you choose active surveillance, you can change your mind at any time and have surgery or radiation, even if tests show that your prostate cancer hasn't changed.

A 15-year study followed men on active surveillance. At 5 years, about 24 out of 100 men had other treatment, either because their prostate cancer had changed or because they didn't want to wait to see if their prostate cancer would change. At 10 years, about 36 out of 100 men had other treatment. And at 15 years, about 45 out of 100 men had other treatment.^{footnote 1}

For men with low-risk prostate cancer and for some men with medium-risk prostate cancer, active surveillance may be a better treatment option than surgery or radiation. Whether active surveillance is a good choice for you is something you will want to discuss with your doctor. You and your doctor will want to consider:

• Your age and how long you expect to live.
• Your PSA level.
• Your Gleason score.
• Your prostate biopsy results.
• The side effects you might have from other treatments.
• Your personal feelings and concerns.

If you choose active surveillance, having a doctor who supports your choice is important. So is the support of others who are close to you.

Watchful waiting means that you'll still be under the care of your doctor. But the goal of watchful waiting is to only treat symptoms that bother you. (For active surveillance, the goal is to cure the cancer if tests show that the cancer is growing.)

Men who are near the end of their lives and men who have other serious medical conditions and aren't well enough to have surgery or radiation often choose watchful waiting.

One of the benefits of active surveillance is that you may be able to avoid treating a cancer that may never be a problem. You also can delay or avoid surgery or radiation and their side effects. The short-term and long-term side effects from having surgery or radiation are serious. They include having trouble getting erections, having urinary problems like not being able to control your bladder, and having bowel problems such as diarrhea or rectal pain.

Another benefit is that you can keep your current quality of life and keep doing the activities you enjoy, at least for a time. Your overall well-being; your physical, mental, and sexual health; and your relationships are all part of your quality of life.

For men with low-risk localized prostate cancer who choose active surveillance, the chance of their cancer spreading is low. One study compared active monitoring (a watch-and-wait program like active surveillance), surgery, and radiation in men who had localized prostate cancer and found that the risk of dying was very low and about the same, no matter what option men chose.^{footnote 2}

There is a chance that your prostate cancer will grow during active surveillance. But if the cancer grows, it can still be successfully treated. Your doctor will recommend treatment, such as surgery or radiation.

If you choose active surveillance, it's very important to follow your doctor's schedule of tests and exams. Regular checkups will increase your chances of finding out right away if your prostate cancer is growing. That way your cancer still can be treated early, when treatments are more successful.

It can be hard to wait to see if your prostate cancer will need treatment. Or you may worry that the cancer might get worse between checkups. Not knowing what might happen may affect your quality of life. Several studies found that 3 to 9 out of 100 men on active surveillance changed their minds and had other treatment because of anxiety (and not due to changes in their prostate cancer).^{footnote 3}

Your doctor might recommend active surveillance if:

• Your cancer isn't likely to grow because your PSA is low, your Gleason score is low, and the cancer is so small it can only be seen through a microscope.
• Your age and current health make you a good candidate for active surveillance.
• You want to delay or avoid surgery or radiation and their side effects.