Prostate Cancer

What is prostate cancer?

Prostate cancer is one of the most common cancers in men. It develops in the prostate, a small gland that forms part of the male reproductive system. The prostate sits between the penis and the bladder, and its role is to produce fluid that helps make up the semen that nourishes and carries sperm during ejaculation.

About one in every nine men will be diagnosed with prostate cancer at some point in his life. In the United States, the American Cancer Society estimated for 2020 about 191,930 new cases of prostate cancer and about 33,330 deaths from the disease.

Types of prostate cancer

Most prostate cancers fall into one of the following types, of which adenocarcinoma is by far the most common:

• adenocarcinomas (most common)
• small cell carcinomas
• neuroendocrine tumours
• transitional cell carcinomas
• sarcomas

Risk factors

The cause of prostate cancer is not fully understood, but it develops when cells in the prostate begin to grow abnormally. Several factors are known to increase the risk:

• Age: men aged 65 or older are more likely to develop prostate cancer.
• Race and ethnicity: African-American men are at higher risk, while Asian-American and Hispanic or Latino men are at lower risk.
• Geography: prostate cancer is most common in North America, north-western Europe, Australia and on the Caribbean islands.
• Family history and genetics: men with a father, brother or several relatives affected are more likely to develop the disease. So too are men who carry inherited mutations in the BRCA1 or BRCA2 genes, which are also linked to a higher risk of breast cancer.

Signs and symptoms

Prostate cancer often causes no symptoms in its early stages. As it becomes more advanced, signs may include:

• problems passing urine, such as a weaker stream or needing to urinate more often
• blood in the urine or semen
• bone pain, or discomfort in the pelvis or other areas where the cancer has spread
• erectile dysfunction
• weakness or numbness in the legs, or loss of bladder or bowel control

How it's diagnosed

Prostate cancer is more treatable when found early, and it may be detected through one or more of the following:

• PSA blood test: a raised level of prostate-specific antigen (PSA) increases the likelihood of prostate cancer, although it can also be raised by other conditions such as benign prostatic hyperplasia (BPH), or inflammation or infection of the prostate.
• Digital rectal examination (DRE): a physical examination to check the prostate for abnormalities.
• Prostate biopsy: usually a core needle biopsy, in which small samples of the prostate are removed to check for cancer. The Gleason system is used to grade and assess the cancer.
• Imaging tests: such as transrectal ultrasound (TRUS), MRI, CT or PET scans.

Treatment options

Once prostate cancer has been diagnosed, your doctor will establish its stage and then discuss the options best suited to your overall health, medical history and staging results. Regular follow-up appointments and periodic monitoring are strongly recommended. Treatment may include:

• Surgery: a common option while the cancer is still localised, though possible side effects include urinary incontinence and erectile dysfunction. The main surgical approaches are:
• radical prostatectomy — removing the entire prostate gland, the seminal vesicles and some surrounding tissue
• robotic or laparoscopic prostatectomy — a less invasive approach using smaller incisions, a camera and instruments, sometimes with a robotic system to assist the surgeon
• transurethral resection of the prostate (TURP) — not used to treat the cancer itself but to relieve symptoms such as urinary blockage, by removing the inner part of the prostate that surrounds the urethra
• Radiotherapy: high-powered energy beams, from sources such as X-rays and protons, used alone or with chemotherapy. Possible side effects include pain, urinary incontinence, rectal symptoms and erectile dysfunction.
• Cryotherapy: using very cold temperatures to freeze and destroy prostate cancer cells.
• Hormonal therapy: drugs, or removal of the testicles (orchiectomy), to stop the body producing testosterone — the male hormone that prostate cancer cells rely on to grow.
• Chemotherapy: drugs given intravenously or orally to kill cancer cells, given in cycles that are often two to three weeks long.
• Immunotherapy: immune cells, or drugs that prompt the immune system, used to kill cancer cells.
• Targeted drug therapy: drugs that act on specific abnormalities within cancer cells.
• Alternative treatments: other evidence-based approaches used to attack cancer cells.

Reducing your risk

There is no guaranteed way to prevent prostate cancer, but you can lower your risk by:

• eating a healthy diet
• exercising regularly
• maintaining a healthy weight, since some studies suggest that being overweight or obese is associated with a higher risk of prostate cancer