Stage 3 prostate cancer is an advanced but still treatable form of the disease. Like other types of cancer, prostate cancer is classified in stages based on how far the disease has progressed.

Stage 1 prostate cancer means the cancer is still confined to the prostate gland, while stage 4 — the most advanced form of the disease — means the cancer has spread to other parts of the body. About 80 to 85 percent of all prostate cancers are diagnosed in stages 1, 2, or 3.

At stage 3, cancer cells have penetrated the thin capsule that surrounds the prostate gland. The malignant cells may have spread to tissue beyond the prostate, or the cancer may still affect the prostate only.

With proper treatment, about 95 percent of individuals with stage 3 prostate cancer will survive for at least 5 years.

Early on, you may notice few if any prostate cancer symptoms. Most patients with localized prostate cancer will not have symptoms. By stage 3, some of the first signs of trouble may be certain urinary concerns, including:

  • a weak stream
  • more frequent urination
  • incontinence
  • nocturia, or having to get up and pee in the middle of the night
  • blood in your urine or semen
  • feeling like you have to pee, but not passing anything

During stage 3, you may also experience pain or discomfort in the pelvic area. Erectile dysfunction may occur by stage 3.

If the doctor conducting a digital rectal exam feels any bumps or hard areas on the prostate, you may be advised to have a biopsy. Likewise, if a PSA test shows elevated PSA levels, your doctor may suggest a biopsy. An MRI may also be used to help determine whether prostate cancer is present.

Prostate cancer requires a biopsy to confirm a diagnosis. A needle biopsy, in which a thin needle is inserted quickly into the prostate to obtain a small piece of tissue, is usually ordered if there are other indications of prostate cancer.

If cancer cells are found, they may be given a Gleason score and your doctor may assign a stage to your cancer.

From there, the decision about how to proceed should be made after a thorough review of the risks and benefits of all treatment options.

Describing a cancer in stages helps doctors and their patients identify the seriousness of the disease and how best to treat it.

Staging system

The system most commonly used was devised by the American Joint Committee on Cancer. It’s known as the TNM system, and it’s based on how much the cancer has spread.

TNM system

  • T to describe the extent of the primary tumor
  • N to state whether the cancer has spread to the lymph nodes
  • M to state whether the cancer has metastasized (or spread) to other tissue in the body

PSA levels

Doctors also rely on your PSA levels to help stage prostate cancer. PSA stands for prostate-specific antigen, a protein produced by the prostate.

High PSA levels are often, though not always, indicative of prostate cancer. PSA levels are measured in nanograms of PSA per milliliter of blood (ng/mL).

PSA results

Lower PSA values are generally considered safe. Most laboratories use a PSA of 4.0 ng/mL as the cutoff for “normal,” but each value must be considered in the appropriate clinical context.

Gleason score

Prostate cancer staging may also include a Gleason score, which is a way of estimating the aggressiveness of the cancer. A Gleason score is actually made up of two scores arrived at by examining a small sample of prostate tissue.

A Gleason score is commonly understood as a series of patterns. The first number is the most common pattern seen and must be more than 50 percent of the tissue. The second number is the second most common pattern and must be less than 50 percent, but more than 5 percent, of the tissue.

How the score looks

Each grade is a number between 1 and 5. You may have a Gleason score of 7, or a 3+4. The higher the score, the more aggressive the cancer is likely to behave.

Though there are variations within each stage, the following is a basic outline of the four stages of prostate cancer.

Stage 1

  • This is the least advanced cancer, where it hasn’t moved out of the prostate gland.
  • The 5-year survival rate is nearly 100 percent.
  • The PSA level is usually under 10 ng/mL, and the Gleason score is typically a 6 or lower.

Stage 2

  • The cancer is still contained in the prostate.
  • The doctor, however, may be able to feel abnormal changes to the prostate during a digital rectal examination.
  • At stage 2, the PSA score is usually less than 20 ng/mL, and the Gleason score can be 6, 7, or 8 (grade group 2, 3, 4).
  • The 5-year survival rate is also nearly 100 percent.

Stage 3

The cancer is growing outside of the prostate gland, but may not have reached the rectum, bladder, or other organs. Stage 3 cancer is also divided into letter subgroups:

  • Stage 3a. The tumor has pushed through the outer capsule on one side of the gland. The PSA level is often 20 ng/mL or higher, and the Gleason score is usually 8 or less.
  • Stage 3b. The tumor has pushed through the capsule with seminal vesicle, rectal, or urethral sphincter invasion. There is no lymph node involvement. The PSA may be any level, and the Gleason score is likely to be 8 or less.
  • Stage 3c. The tumor can be contained or is growing outside the prostate. There is no lymph node involvement. The PSA can be at any level and the Gleason score is 8 or less.
  • If the cancer hasn’t spread far, the 5-year survival rate at stage 3 is still almost 100 percent.

Stage 4

  • Stage 4 cancer is divided into letter subgroups depending on whether it has invaded the nearby lymph nodes (stage 4a) or whether it has reached distant lymph nodes or other organs, tissue, or even the bones (stage 4b).
  • This is the most advanced form of prostate cancer.
  • Any PSA level and Gleason score are possible.
  • The 5-year survival rate is about 30 percent.

What 5-year survival rates mean

It’s important to understand what survival rates mean. In this case, the number refers to the percentage of people who are still living five years after initial diagnosis. This means those people have lived at least five years after diagnosis. Many survival rates do not look beyond that timeframe.

Prostate cancer treatments range from active surveillance, which is a watch and wait approach to the slow-growing cancer, to invasive procedures. Procedures include surgery to remove the prostate and brachytherapy, which is the injection of radioactive “seeds” into the prostate to kill cancer cells.

Treatment options for stage 3 prostate cancer include:

  • external beam radiation and hormone therapy
  • external beam radiation and brachytherapy, along with hormone therapy
  • radical prostatectomy, which is the surgical removal of the entire prostate and some surrounding tissue, including the seminal vesicles
  • a pelvic lymph node dissection, which involves removing lymph node tissue

These approaches are known as “local” treatments because they treat the cancer in or close by the prostate gland.

A note about hope

Prostate cancer is usually a slow-growing cancer, so even if it is diagnosed at stage 3, there are very effective treatments available. And new developments in prostate cancer treatment are being made every year.

Prostate cancer is the most common type of cancer among men in the United States and should therefore be a subject that men learn about and address with their doctors once they reach adulthood.

Because prostate cancer is slow growing, regular prostate screenings can often catch the disease in its early stages. The American Cancer Society recommends the following timeframe for initial prostate screenings:

  • age 40 for men with more than one first-degree relative (brother or father) who had prostate cancer at an early age
  • age 45 for men at high risk of developing prostate cancer, including African Americans and anyone with a first-degree relative who was diagnosed with cancer younger than 65 years of age
  • age 55 to 69 for men who are of average risk of prostate cancer

The issue of prostate cancer screenings is a somewhat controversial one, so talk with a primary care physician or urologist about the pros and cons of getting a screening at your age.

Stage 3 prostate cancer, while an advanced form of the disease, can often be successfully treated. It may involve surgery or other procedures that can affect an individual’s urinary and sexual function.

However, stopping prostate cancer from potentially spreading throughout the body could be worth the costs of aggressive cancer treatment. Your age, health, and how prostate cancer and its treatment may affect your quality of life should be part of a thorough conversation with your doctor.