Prostate cancer - symptoms, risk factors, and treatment

Prostate cancer is the most common cancer among men after skin cancer, with approximately 1 in 8 men diagnosed in their lifetime.  

What is the prostate gland?

The prostate is a small, walnut-sized gland in males that makes some of the fluid in semen.  It is located below the bladder in front of the rectum.  The urethra, a tube that carries urine and semen out of the body through the penis, goes through the center of the prostate.

Prostate cancer risk factors 

Age and prostate cancer risk 

Age is a significant risk factor for prostate cancer, with the likelihood of developing the disease increasing as men grow older. According to the American Cancer Society, about 60% of all prostate cancer cases are diagnosed in men 65 or older with an average diagnosis age of 66. Prostate cancer is rare in men under the age of 40 but increases after age 50 and by age 80, the chance of developing prostate cancer is nearly 60%. 

Family history and genetics 

Family history and genetic factors play a significant role in prostate cancer risk. Men whose father, brother, or son were diagnosed with prostate cancer have a 2 to 3 times higher risk of developing the disease.

Doctors may recommend men who have a family history of prostate cancer start prostate cancer screening at an earlier age of 40–45.

Race and ethnicity

Race and ethnicity are important factors in determining prostate cancer risk.  African American men face a higher risk compared to other racial and ethnic groups and are 1.7 times more likely to be diagnosed with prostate cancer and 2.1 times more likely to die from the disease compared to non-Hispanic white men. Black men in the U.S. and Caribbean have the highest incidence of prostate cancer rates in the world.

Prostate cancer symptoms

Screenings can find most prostate cancers early but not everyone chooses to get screened for prostate cancer. Whether or not you are screened regularly, knowing the signs and symptoms of prostate cancer is important. 
 
Early prostate cancer usually causes no symptoms, but symptoms of early prostate cancer might include:

• Problems urinating, including a slow or weak urinary stream or the need to urinate more often, especially at night
• Blood in the urine or semen

Advanced prostate cancer means it has grown larger and has possibly spread to other areas. Advanced prostate cancer can cause problems with urination and blood in the urine or semen, as well as other symptoms, including:

• Trouble getting an erection (erectile dysfunction or ED).
• Pain in the hips, back (spine), chest (ribs), or other areas, from cancer that has spread to the bones.
• Weakness or numbness in the legs or feet, or even loss of bladder or bowel control, from cancer in the spine pressing on the spinal cord.
• Weight loss.
• Feeling very tired.

Any of these symptoms should be shared with your health care provider.

 How Prostate cancer is found

Most prostate cancers are first found through a Prostate-specific antigen (PSA) blood test. 

PSA is a protein made by cells in the prostate gland, both normal cells and cancer cells. While PSA is mostly in semen, a small amount is also found in the blood.

The PSA level in blood is measured in units called nanograms per milliliter (ng/mL). The chance of having prostate cancer goes up as the PSA level goes up, but there is no set cutoff point that can tell for sure if a man does or doesn’t have prostate cancer.

If prostate cancer is suspected based on results of screening tests or symptoms, further tests will be needed to be verified. The actual diagnosis of prostate cancer can only be made with a prostate biopsy, which involves removing tissue from the prostate and testing it in a lab.

The Gleason Score and prostate cancer grading

Prostate tissue samples are examined under a microscope by a pathologist who assigns a grade to the cancer. 

Traditionally, prostate cancer grades were described according to the Gleason Score, named for the pathologist Dr. Donald Gleason who developed it in the 1960s. Dr. Gleason realized that cancerous cells fall into 5 distinct patterns as they change from normal cells to tumor cells. The cells were graded on a scale of 1 to 5, with grade 1 cells resembling normal prostate tissue and cells that have mutated so much that they barely resemble normal cells being graded as grade 5.
 

Today, pathologists do not use the lowest Grades 1 and 2 and instead assign a grade based on how abnormal the biopsy tissue appears.  The pathologist examines the sample and assigns one Gleason grade to the most predominant pattern and a second Gleason grade to the second most predominant pattern. The two grades are then added together for a Gleason score ranging from 6 to 10, with 6 being the lowest grade of cancer.

What Does it Mean?

A Gleason score of 6 is low grade, 7 is intermediate grade, and a score of 8 to 10 is high grade cancer. Gleason 7 scores are further divided into 3+4, in which the less-aggressive Grade 3 cells predominate and 4+3, which contain more Grade 4 cells.

It’s also important to know whether any cells rated at Gleason grade 5 are present, even in just a small amount, and most pathologists will report this. Having any Gleason grade 5 in the biopsy sample or prostate tissue following surgery puts the patient at a higher risk of recurrence.

Prostate cancer stages 

Stage 1

Stage 1 prostate cancer is limited to the prostate gland, which means that it has not spread to nearby lymph nodes or other areas of the body. Additionally, patients with cancer at this stage have a Gleason score of six or lower, and their PSA level is nine or lower.

Stage 2

Prostate cancer that is designated as stage 2 is still limited to the prostate gland and has not spread elsewhere. However, at stage 2, the patient’s Gleason score is seven or higher and their PSA level is at least 10, but less than 20.

Stage 3

At stage 3, it’s possible that the cancer still hasn’t spread outside the prostate, but the PSA level is at least 20. Prostate cancer is also considered stage 3 when the cancer has spread beyond the outer layer of the prostate (for instance, it may have spread to the seminal vesicles or other tissues next to the prostate), but it has not spread to the lymph nodes. The patient’s PSA can be any level, and the Gleason score can be anywhere between two and 10.

Stage 4

Stage 4 prostate cancer has spread to nearby lymph nodes, tissues near the prostate, or even distant parts of the body, such as the bones or distant organs. Similar to stage 3, stage 4 prostate cancer can involve any PSA levels and Gleason scores that range between two and 10.

How Prostate cancer is treated

The stage of prostate cancer is the most important factor in determining a treatment plan, which can include surgery, radiation therapy, hormone therapy, chemotherapy, targeted therapy and immunotherapy. 
 
Doctors consider the size of the cancer, whether it has spread to other parts of the body, how fast it's growing and the patient’s overall health and treatment preference. 

Prostate cancer survival rates

The survival rate of prostate cancer is exceptionally high because it grows very slowly and responds well to treatment.  Because of this, the majority of men diagnosed with prostate cancer are able to lead long and healthy lives. 

According to the American Cancer Society, the five-year survival rate for both localized cancer,  has not spread beyond the prostate and regional, has not spread to nearby structures or lymph nodes, is nearly 100%. For advanced-stage diagnoses, that number drops to 32%.