What is the prostate, and how common is the cancer?
It's a walnut-size gland that lies at the base of the bladder and surrounds the urethra. In the United States prostate cancer is one of the two most frequently diagnosed cancers in men (the other is skin cancer). The American Cancer Society (ACS) estimates that one man in seven will be diagnosed with prostate cancer during his lifetime. However, only about one in 39 will die from the disease.
Risk increases with age. Men 65 or older account for most of the cases diagnosed. African American men appear to be at greater risk than white men, and an individual's odds may be higher than average if the disease runs in his family.
How can I prevent prostate cancer?
You may be able to reduce your risk of prostate cancer by improving your diet. Researchers at Harvard University found that men who ate cooked tomatoes or foods made with them (tomato sauce or ketchup, for instance) more than twice a week were less likely to develop prostate cancer. Tomatoes are particularly rich in the antioxidant lycopene. (An antioxidant is a substance that can neutralize unstable molecules which may trigger cancer.) Grapefruit and watermelon are also rich in lycopene.
Studies on lycopene are not conclusive, but it may have particular power to stop healthy prostate cells from turning malignant. (Since cooking tomatoes releases lycopene more thoroughly, tomato sauce offers better protection than fresh tomatoes.) Eat lots of other fruits and vegetables as well; they contain other natural antioxidants thought to guard against many forms of cancer.
Cutting back on saturated fat -- the kind found in meat, dairy products, and most pastries -- is a good idea, too. A study funded by the National Cancer Institute showed that prostate cancer was linked to diets high in this type of fat. Some studies also suggest that regular physical activity may lower the risks of all types of cancer, including the kind that develops in the prostate.
What are the symptoms?
In early stages, prostate cancer generally has no symptoms, so most cases are detected by screening tests. Some men do notice that they have to urinate more often or that their stream of urine is weaker. But those changes can also arise from a less serious condition like an enlarged prostate. Advanced prostate cancer may result in swollen lymph nodes in the groin, problems maintaining an erection, and pain in the groin area, spine, hips, or ribs. If you have any of these symptoms, see your doctor.
Can my doctor test for prostate cancer?
Yes. He or she will use two basic screening methods. Neither is perfect; both have high false-positive rates, meaning that they frequently indicate cancer when there is none. The tests may also detect slow-growing tumors that will never get large enough to harm you. One is known as a digital rectal examination (DRE), in which your doctor checks for lumps or other abnormalities by feeling your prostate with a gloved finger.
The other is a blood test called the prostate-specific antigen test (PSA) which measures a substance that typically increases in men when they have prostate cancer. If the PSA test is high (for a man over 50, a score of 4 or higher), or has risen compared with a previous test, your doctor may do a biopsy on your prostate tissue. The sample will then be examined for cancerous cells. Unfortunately, PSA levels can be misleading. According to a report in the New England Journal of Medicine, 15 percent of a group of 2,950 men with normal PSA levels were still found to have prostate cancer.
Because testing may uncover very slow-growing cancers that never would have affected a man's lifestyle, and because it may lead to unnecessary anxiety or treatments, the ACS does not recommend routine testing at this time. The ACS recommends that each man discuss the pros and cons of testing with his doctor so he can decide if testing is right for him. If he decides to be tested, the ACS recommends both the PSA and the DRE, since the DRE can uncover cancers in men with normal PSAs.
If the biopsy shows cancer, is there a way to find out if it's the dangerous, fast-growing kind?
Doctors use a method called the Gleason system to estimate how aggressive a prostate cancer may be. Malignant cells are examined under a microscope and graded on a scale of 1 to 10 according to how different they look from normal cells. The Gleason score is far from conclusive; still, the higher the score, the more likely the cancer will grow and spread rapidly. Doctors may also look at changes in your PSA level over time to gauge the cancer's aggressiveness.
What are my treatment options?
Treatment depends on many factors, including your age and life expectancy, the stage and grade of your cancer, your general health, and your feelings about treatment. If tumor cells are found only in the prostate itself, doctors may remove your prostate or use radiation therapy to kill the cells. A newer treatment involves embedding tiny radioactive seeds in the prostate. If the cancer has spilled out of the prostate gland into surrounding tissue, hormone therapy in the form of pills, shots, or both can slow the growth of malignant cells, sometimes dramatically so. Hormone therapy does not cure the cancer, but it can provide relief from symptoms.
Some patients choose to do nothing, an approach called "watchful waiting." This may sound alarming, but it may make sense, particularly for older men whose tumors are most likely to be slow growing. The majority of men who reach age 85, in fact, have cancerous prostate cells, but the disease is developing so gradually that it never threatens their quality of life.
What are the risks of aggressive treatment?
The biggest worries men face are losing their ability to get an erection or to control their bladder. Unfortunately, surgery and radiation entail some danger of both. Your own odds are difficult to calculate precisely, since the risk of these side effects depends on your age, the extent of the disease, and the type of surgery performed. However, a new experimental treatment for prostate cancer offers new hope for remission without these side effects.
This treatment -- a laser-activated drug treatment called VTP -- spares the prostate during treatment and so avoids the side effects of urinary incompetence and erectile dysfunction. A clinical trial in Europe found that half the patients were in remission after two years. Researchers cautioned, however, that it may be several years until it is available to the public.
In the meantime, a surgical nerve-sparing technique, introduced in the 1980s, has reduced the incidence of impotence, but it's not appropriate for all men. And the troubling fact remains that between 65 and 90 percent of patients whose prostates are removed suffer some inability to maintain an erection. A smaller percentage lose some degree of bladder control. Others may experience occasional urinary dribbling when they exert themselves or cough. Talk to your doctor about the best ways to deal with these problems.
What's being done to improve detection and treatment?
Plenty. The National Cancer Institute is funding studies on a wide variety of new treatments, including hormones that block the growth of tumor cells and substances that cut off a tumor's blood supply. Researchers are also looking for better ways to distinguish between slow-growing and fast-growing prostate cancers. And the laser therapy discussed above shows great promise, according to researchers. "This is truly a huge leap forward for prostate cancer treatment, which has previously lagged decades behind other solid cancers, such as breast cancer," said chief investigator and urologist Dr. Mark Emberton of the University College London Hospital in a public statement.
National Cancer Institute, www. nci.nih.gov
American Cancer Society, www.cancer.org
Laser-Activated Drug Offers New Hope for Prostate Cancer Treatment. CNN. December 20, 2016. www.cnn.com/2016/12/20/health/prostate-cancer-laser-drug-treatment/index.html
Giovannucci, Edward et al, "A Prospective Study of Tomato Products, Lycopene, and Prostate Cancer Risk", JNCI, Vol. 94, No. 5, 391-398.
California Department of Health Services. State health director warns consumers about prescription drugs in herbal products.
BotanicLab Pursues Investigation of "Compound" Found In PC SPES, Business Wire.
Thompson IM, et al. Prevalence of prostate cancer among men with a prostate-specific antigen level less than or equal to 4.0 ng per milliliter. N Engl J Med 350:2239-2246.
Prostate Cancer. Medline Plus. http://www.nlm.nih.gov/medlineplus/ency/article/000380.htm
American Cancer Society. What Are Key Statistics About Prostate Cancer? http://www.cancer.org
American Cancer Society. How Many Men Get Prostate Cancer? http://www.cancer.org
University of Pittsburgh Medical Center, Cancer Centers. Prostate Cancer: Erectile Dysfunction.
National Cancer Institute. Questions and Answers about PC-SPES.
American Cancer Society. How is prostate cancer found?