Prostate cancer is cancer that occurs in the prostate, a small walnut-shaped gland in men that produces the seminal fluid that nourishes and transports sperm. Prostate cancer is one of the most common types of cancer in men, affecting 165,000 men in the United States annually. Usually prostate cancer grows slowly and is initially confined to the prostate gland, where it may not cause serious harm. However, while some types of prostate cancer grow slowly and may need minimal or even no treatment, other types are aggressive and can spread quickly. Prostate cancer that’s detected early, when it’s still confined to the prostate gland, has a better chance of successful treatment.
Prostate cancer may cause no signs or symptoms in its early stages, but in more advanced cases signs and symptoms can be trouble urinating; decreased force in the stream of urine; blood in semen; discomfort in the pelvic area; bone pain; and erectile dysfunction.
One in nine men will develop prostate cancer in their lifetime, and while a cause is still unknown, there are several factors that can increase a man’s risk.
- Age: Prostate cancer risk increases with age.
- Race: For reasons not yet determined, black men carry a greater risk of prostate cancer than do men of other races. In black men, prostate cancer is also more likely to be aggressive or advanced.
- Family history: If men in your family have had prostate cancer, your risk may be increased. Also, if you have a family history of genes that increase the risk of breast cancer (BRCA1 or BRCA2) or a very strong family history of breast cancer, your risk of prostate cancer may be higher.
- Obesity: Obese men diagnosed with prostate cancer may be more likely to have advanced disease that’s more difficult to treat.
Standard recommendations for prostate cancer screening are for men to begin these screenings at age 50, or sooner for those at a higher risk. Prostate screening tests might include:
- Digital rectal exam (DRE). During a DRE, your doctor inserts a gloved, lubricated finger into the rectum to examine the prostate, which is adjacent to the rectum. Further testing might be done if any abnormalities are found in the texture, shape or size of the gland.
- Prostate-specific antigen (PSA) test. A blood sample is drawn from a vein in the arm and analyzed for PSA, a substance that’s naturally produced by the prostate gland. It’s normal for a small amount of PSA to be in the bloodstream. However, if a higher than normal level is found, it may indicate prostate infection, inflammation, enlargement or cancer.
- If a patient has a high PSA level or has an abnormal DRE result, a transrectal ultrasound may be used for further testing, along with a prostate biopsy.
When a biopsy confirms the presence of cancer, the next step is to determine the level of aggressiveness (grade) of the cancer cells. A laboratory pathologist examines a sample of the cancer to determine how much cancer cells differ from the healthy cells. A higher grade indicates a more aggressive cancer that is more likely to spread quickly. The most common scale used to evaluate the grade of prostate cancer cells is called a Gleason Score – which combines two numbers and can range from 2 (nonaggressive cancer) to 10 (very aggressive cancer). To help determine if the cancer has spread beyond the prostate, bone scans, ultrasounds, CT scans, MRI’s and PET scans may be used.
For men diagnosed with low-risk prostate cancer, treatment may not be necessary right away. Some men may never need treatment, instead active surveillance may be recommended. In active surveillance, regular follow-up blood tests, rectal exams and possibly biopsies may be performed to monitor progression of the cancer. If tests show the cancer is progressing, surgery or radiation treatment may be suggested. Active surveillance may be an option for cancer that isn’t causing symptoms, is expected to grow very slowly and is confined to a small area of the prostate; but it also carries a risk that the cancer may grow and spread between checkups, making it less likely to be cured.
Surgery for prostate cancer involves removing the prostate gland (radical prostatectomy), some surrounding tissue and a few lymph nodes. Radical prostatectomy can be performed in several ways:
- Using a robot to assist with surgery. During robot-assisted surgery, the instruments are attached to a mechanical device (robot) and inserted into the abdomen through several small incisions. The surgeon sits at a console and uses hand controls to guide the robot to move the instruments. Robotic prostatectomy may allow the surgeon to make more-precise movements with surgical tools than is possible with traditional minimally invasive surgery.
- Making an incision in your abdomen. During retropubic surgery, the prostate gland is taken out through an incision in the lower abdomen.
Radiation therapy uses high-powered energy to kill cancer cells. Prostate cancer radiation therapy can be delivered in two ways:
- Radiation that comes from outside of your body (external beam radiation). During external beam radiation therapy, you lie on a table while a machine moves around your body, directing high-powered energy beams, such as X-rays or protons, to your prostate cancer. You typically undergo external beam radiation treatments five days a week for several weeks.
- Radiation placed inside your body (brachytherapy). Brachytherapy involves placing many rice-sized radioactive seeds in your prostate tissue. The radioactive seeds deliver a low dose of radiation over a long period of time. Your doctor implants the radioactive seeds in your prostate using a needle guided by ultrasound images. The implanted seeds eventually stop emitting radiation and don’t need to be removed.
Hormone therapy is treatment to stop the body from producing the male hormone testosterone. Prostate cancer cells rely on testosterone to help them grow. Cutting off the supply of testosterone may cause cancer cells to die or to grow more slowly. Hormone therapy options include medications that stop the body from producing testosterone; medications that block testosterone from reaching cancer cells; and surgery to remove the testicles (orchiectomy). Hormone therapy is used in men with advanced prostate cancer to shrink the cancer and slow the growth of tumors. In men with early-stage prostate cancer, hormone therapy may be used to shrink tumors before radiation therapy, which can increase the likelihood that radiation therapy will be successful.
Cryosurgery or cryoablation involves freezing tissue to kill cancer cells. During cryosurgery for prostate cancer, small needles are inserted in the prostate using ultrasound images as guidance. A very cold gas is placed in the needles, which causes the surrounding tissue to freeze. A second gas is then placed in the needles to reheat the tissue. The cycles of freezing and thawing kill the cancer cells and some surrounding healthy tissue. Cryosurgery is more frequently used as a salvage therapy for men who haven’t been helped by radiation therapy.
Chemotherapy uses drugs to kill rapidly growing cells, including cancer cells, and can be administered through a vein in the arm, in pill form or both. Chemotherapy may be a treatment option for men with prostate cancer that has spread to remote body locations, or for cancers that don’t respond to hormone therapy.
Immunotherapy (Biological Therapy) uses your body’s immune system to fight cancer cells. One type of biological therapy called sipuleucel-T (Provenge) has been developed to treat advanced, recurrent prostate cancer. This treatment takes some of your own immune cells, genetically engineers them in a laboratory to fight prostate cancer, then injects the cells back into your body through a vein. Some men do respond to this therapy with some improvement in their cancer, but the treatment is very expensive and requires multiple treatments.