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Prostate cancer: When is a biopsy necessary?

A biopsy is a direct examination of prostate tissue under a microscope to check for cancer cells.

When screening tests suggest that a man has prostate cancer, a biopsy may be suggested to find out for sure.

For example, a biopsy may be recommended if a man has increased PSA (prostate-specific antigen) levels in the blood or a suspicious lump felt during a digital rectal exam.

Before performing a biopsy, your doctor might choose to do further testing, such as ultrasound imaging or more PSA testing, to help determine if cancer or another prostate condition is the problem.

Before having a biopsy, you may want to talk with your doctor about your test results and other factors, such as your prostate cancer risk and your overall health status, according to the National Cancer Institute (NCI).

Remember, needing a biopsy does not mean that you have cancer. In fact, most men who have a prostate biopsy after a routine exam don't have cancer, the NCI reports.

How it's done

In a prostate biopsy, a small amount of prostate gland tissue is removed and sent to a lab, where it is checked for cancer cells. A biopsy is usually done in a doctor's office by a specialist called a urologist.

Most often, the urologist uses ultrasound imaging to help guide a special needle into the prostate via the rectum wall. In this technique, called transrectal ultrasound, a small probe inserted in the rectum sends out sound waves that are used to make pictures on a video screen. The needle can then be used to take several samples of the prostate tissue. A local anesthetic can help ease discomfort, and the entire procedure may take about 10 minutes, according to the American Cancer Society (ACS).

Side effects, such as bleeding and infection, are possible, though antibiotics are usually given ahead of time to help prevent infection.

After the test

The time it takes to get biopsy results can vary, but they may be ready as soon as a day or two after the lab gets the sample, according to the ACS.

If the biopsy uncovers cancer, doctors will examine the disease cells from the test sample and predict how fast the tumor is likely to grow—an important factor when making treatment decisions.

False negative results are unusual but possible. This means that there is a cancer in the prostate, but the biopsy did not detect it. This can happen if the biopsy needle misses the cancerous area of the prostate.

If a biopsy fails to find cancer but the disease is strongly suspected—due to very high PSA test results, for example—you may need to repeat the procedure, according to the ACS.

Learn more

For more information about prostate cancer, visit one of the following websites:

Reviewed 1/9/2022

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