Prostate cancer is the second most common form of cancer in men. Around one in seven men are diagnosed with prostate cancer throughout a lifetime, according to the American Cancer Society (ACS) and 1 man in 38 will die of prostate cancer. So, it is important to know a little more about this deadly disease. 

Causes

The prostate is a gland located beneath a man's bladder, toward the front of the rectum. About the size of a walnut, it surrounds the urethra, the tube that carries urine from the bladder. The prostate produces seminal fluid, which nourishes and transports sperm.

Prostate cancer is often caused by genetics. In fact, 5 percent to 10 percent of prostate cancer cases are believed to be caused by high-risk genetic factors, according to the National Cancer Institute (NCI). Other factors, such as testosterone levels, diet and certain vitamins are believed to contribute to the growth of cancer in the prostate, according to the NCI.

Risks and symptoms

There may be no warning signs of prostate cancer. In more advanced stages — when the prostate has enlarged — symptoms may include trouble urinating, blood in the urine or semen, erectile dysfunction or pain in the lower back, hips or thighs, according to the Mayo Clinic.

According to the ACS, the disease is more prevalent in men older than 40 years. The chances of being diagnosed with prostate cancer for men 49 years or younger is 1 in 304 for men. As men age, the chance of being diagnosed grows. One in 44 for men aged 50 through 59 years are diagnosed with prostate cancer while one in 16 for men aged 60 through 69 years and diagnosed, and one in nine for men aged 70 years and older are diagnosed with prostate cancer, according to the ACS.

For reasons that are not well understood, prostate cancer is more common among African-American men and Caribbean men of African ancestry, according to the ACS. It's less common, however, in Asia, Africa, Central and South America than it is in Europe, North America, Australia and other regions.

In 2015, about 27,540 men are expected to die of prostate cancer, though most men diagnosed with the condition do not die from it, according to the ACS. 

Screening and diagnosis

There is no universally agreed-upon schedule or timeframe for screening men who may be at risk for prostate cancer. Some medical organizations recommend screening all men over the age of 50, and earlier screening for men who may be at higher risk, such as African-Americans or men with a family history of prostate cancer. 

Men who have a weak urine stream, difficulty stopping a urine stream, a dribbling stream or blood in their urine or semen may wish to talk to their health care provider about those or any related symptoms, according to the Mayo Clinic.

It should be noted that some of the symptoms of prostate cancer — weak or dribbling urine stream — are similar to the symptoms of benign prostatic hyperplasia, or BPH, a common condition that's sometimes referred to as prostate gland enlargement.

The doctor or health care provider will probably request a urinalysis (urine test) to rule out an infection or other condition, according to the Mayo Clinic. A digital rectal exam (DRE), in which the doctor inserts a gloved finger into the rectum to check the prostate, is also commonly performed.  According to Dr. Mitchell Gaynor, an oncologist in New York City and author of "The Gene Therapy Plan" (Viking, 2015), a rectal exam isn't typically uncomfortable as long as plenty of lubricant is used. "If there is a significant amount of discomfort, that is an indication of an underlying infection, either acute or chronic prostatitis, and many men are walking around with this inflammation unknowingly," said Gaynor.  

The doctor may also order a prostate-specific antigen (PSA) test, according to the ACS. A PSA is a blood test that determines the amount of PSA in the bloodstream. PSA is a substance produced by the prostate; elevated PSA levels may be an indication of infection, inflammation, enlargement or cancer. 

"A huge misconception about prostate cancer is that the PSA test is the be-all and end-all in detecting the presence of prostate cancer — it measures a variety of conditions but does not tell if the patient actually has cancer," Gaynor told Live Science. "The better test is the PCA3, which is a urine test that will pick up prostate cancer specifically. The PSA is not the panacea of prostate cancer detection that was previously thought. The PSA is a 'prostate test' not a 'prostate cancer test.'" 

If any of these procedures detects an abnormality, the doctor may recommend additional tests, such as an ultrasound of the prostate or a biopsy of tissue collected from your prostate. 

Treatment

Treatment of prostate cancer depends in part on your age, general health and the degree to which the cancer has spread, or its stage. Stage I prostate cancer is described as a very early cancer and confined to a small area of the prostate, according to the NCI.

Stage II prostate cancer is more aggressive and may have spread to both sides of the prostate gland. Stages III and IV describe cancer that has spread beyond the prostate gland to other tissues or organs, according to the NCI.

Many doctors recommend active surveillance or "watchful waiting" — including blood tests, rectal exams, biopsies and other procedures — to see if more aggressive treatment is necessary. Surveillance may be an option when prostate cancer is very slow growing or limited in scope.

There are two types of radiation therapy used to treat prostate cancer, according to the Mayo Clinic. External beam radiation uses a large machine to direct radiation to the prostate and other affected tissue. Brachytherapy, in which numerous small implants (about the size of a grain of rice) are placed inside the body, delivers a low dose of radiation over a long period of time.

Prostate cancer cells rely on the male hormone testosterone to grow, according to the Mayo Clinic. Hormone therapy can reduce the amount of testosterone in your body, thereby limiting the growth of cancer cells. Some doctors recommend drugs that stop the body from producing testosterone; other drugs may be used to block the hormone from reaching cancer cells.

Some doctors may also recommend surgery to remove the testicles (which produce testosterone) in a procedure known as an orchiectomy.

Surgery to remove the prostate gland (prostatectomy) is an option at all stages of prostate cancer. In most cases, the surgery will involve the removal of the entire prostate gland and nearby lymph nodes. A prostatectomy can result in urinary incontinence and erectile dysfunction, according to the Mayo Clinic.

For advanced cases of prostate cancer, some doctors recommend chemotherapy to kill cancer cells, or immunotherapy, which stimulates the immune system to destroy cancer cells. 

Life after prostate cancer treatment

Prostate cancer can recur following treatment. A health care provider will address any changes and suggest additional treatments as appropriate. The survival rates of those after prostate cancer diagnosis are quite good. The relative five-year survival rate is almost 100 percent, the 10-year survival rate is 99 percent and the 15-year relative survival rate is 94 percent, according to the American Cancer Society.

Regular checkups and other procedures are usually scheduled for people who have been treated for prostate cancer. These may include a DRE, a PSA test or other procedures. Your doctor will also be able to offer help in coping with the side effects of prostate cancer treatment.

Men who have had prostate cancer may benefit from cancer support groups, nutrition, interacting with family and loved ones and exercise, according to the Mayo Clinic.