Understand prostate cancer

Prostate cancer is most common in older men. In the US, about 1 out of 5 men will be
diagnosed with prostate cancer.

The information on this page may help you gain a better understanding of a prostate cancer diagnosis and prepare you to make important decisions with your doctor.

What is prostate cancer?

Prostate Cancer Starts When Cells Begin to Grow Out of Control in the Prostate Gland

The prostate gland is found only in males. It’s found below the bladder and in front of the rectum. Prostate cancer starts when cells begin to grow out of control in the prostate gland. This cancer is one of the types of cancer that may spread slowly to other areas of the body. People with prostate cancer may not have symptoms or problems for years, or in their lifetime.

More than half of men diagnosed with prostate cancer are over 65 years old. African American men are significantly more likely to be diagnosed with prostate cancer than white men. However, nearly 90% of cases are found before the cancer spreads from the prostate to other organs.

Stages of prostate cancer

From the National Cancer Institute (NCI)

The information below is based on information originally published by the National Cancer Institute (NCI), the US government’s main agency for cancer research. Use this information to talk to your doctor about your specific stage of prostate cancer.

The stage of the cancer is based on the results of the staging and diagnostic tests, including the prostate-specific antigen (PSA) test and the Grade Group.

PSA levels and Grade groups of prostate cancer

The PSA test measures the level of PSA in the blood. PSA is a substance made by the prostate that may be found in an increased amount in the blood of men who have prostate cancer.

The Grade Group depends on the Gleason score:

  • Grade Group 1 is a Gleason score of 6 or less.
  • Grade Group 2 or 3 is a Gleason score of 7.
  • Grade Group 4 is a Gleason score 8.
  • Grade Group 5 is a Gleason score of 9 or 10.

Stage I (1) prostate cancer


In stage I, the cancer is found in the prostate only.

  • The cancer is not felt during a digital rectal exam and is found by needle biopsy (done for a high PSA level) or in a sample of tissue removed during surgery for other reasons (such as benign prostatic hyperplasia). The PSA level is lower than 10 and the Grade Group is 1.

Or stage I can be

  • The cancer is felt during a digital rectal exam and is found in one-half or less of one side of the prostate. The PSA level is lower than 10 and the Grade Group is 1.

Stage II (2) prostate cancer

In stage II, cancer is more advanced than in stage I, but has not spread outside the prostate. Stage II is divided into stages IIA, IIB, and IIC.

In stage IIA

  • The cancer is found in one-half of less of one side of the prostate. The PSA level is at least 10 but lower than 20 and the Grade Group is 1.

Or stage IIA can be

  • The cancer is found in more than one-half of one side of the prostate or in both sides of the prostate. The PSA level is lower than 20 and the Grade Group is 1.

In stage IIB

  • The cancer is found in one or both sides of the prostate. The PSA level is lower than 20 and the Grade Group is 2.

In stage IIC

  • The cancer is found in one or both sides of the prostate. The PSA level is lower than 20 and the Grade Group is 3 or 4.

Stage III (3) prostate cancer

Stage III is divided into stages IIIA, IIIB, and IIIC.

In stage IIIA

  • The cancer is found in one or both sides of the prostate. The PSA level is at least 20 and the Grade Group is 1, 2, 3, or 4.

In stage IIIB

  • The cancer has spread from the prostate to the seminal vesicles or to nearby tissue or organs, such as the rectum, bladder, or pelvic wall. The PSA can be any level and the Grade Group is 1, 2, 3, or 4.

In stage IIIC

  • The cancer is found in one or both sides of the prostate and may have spread to the seminal vesicles or to nearby tissue or organs, such as the rectum, bladder, or pelvic wall. The PSA can be any level and the Grade Group is 5.

Stage IV (4) prostate cancer

Stage IV is divided into stages IVA and IVB.

In stage IVA

  • The cancer is found in one or both sides of the prostate and may have spread to the seminal vesicles or to nearby tissue or organs, such as the rectum, bladder, or pelvic wall. Cancer has spread to nearby lymph nodes. The PSA can be any level and the Grade Group is 1, 2, 3, 4, or 5.

In stage IVB

  • The cancer has spread to other parts of the body, such as the bones or distant lymph nodes. Prostate cancer often spreads to the bones.