More than 180,000 North American men will be diagnosed with prostate cancer this year, and more than 26,000 of those men will eventually die from the disease. Prostate cancer, unlike most other cancers, tends to grow very slowly and does not kill the majority of men who have it. In the United States, the average age for men when first diagnosed is 66. Because most men with prostate cancer do not die from it and often have no symptoms, the United States Preventive Services Task Force, an independent panel of experts picked by the government, has recommended against routine screening for prostate cancer with the PSA test since 2012.
The Latest Information
A new study followed more than 1500 men with prostate cancer for ten years (New England Journal of Medicine, September 14, 2016). This is the first study to compare treatment with surgery or radiation to no treatment at all ("watchful waiting"). At the end of ten years, the researchers reported:
• Survival Rates: Men newly diagnosed with prostate cancer had a 99 percent survival rate whether they were treated with surgery, radiation, or being followed and not treated unless their cancer progressed. They all had a 99 percent 10-year survival rate regardless of treatment group.
• Spread of the Cancer: The cancer progressed in a little over 20 percent of the watchful-waiting group and in 10 percent of the surgery and radiation groups. No enlargement of the cancer in the prostate and no spread of the cancer to other parts of the body was found in more than 75 percent of the men who received no treatment. Those who showed signs of their cancer spreading were then treated.
• Disadvantages of Treatments (Surgery or Radiation): Both the surgery and the radiation treatment groups had increased risk for urinary incontinence, loss of sexual function and heart attacks. Men who were treated with surgery were most likely to suffer lingering impotence and urinary incontinence. Those given radiation had higher risk of suffering leakage of stool for about six months after treatment and temporary reduced sexual function, but had far less urinary incontinence. Radiation treatment has a higher association with heart attacks later on.
• Disadvantages of Watchful-Waiting: The watchful-waiting participants had to have yearly prostate biopsies to see if the cancer was growing.
Study Details and Conclusions
More than 82,000 men ages 50 to 69 were given a PSA blood test between 1999 and 2009. Of 2,664 men who received a diagnosis of prostate cancer, more than half decided to get surgery or radiation and thus could not be considered for an active monitoring research study. However, 1,643 men agreed to be randomized to one of three groups to receive the most common prostate cancer treatments:
Group 1) surgery – radical prostatectomy (553 men)
Group 2) radiation (545 men)
Group 3) active monitoring but no treatment (545 men)
The researchers note that today, 40 to 50 percent of North American men choose watchful waiting after being first diagnosed with prostate cancer. They recommend that active monitoring with no initial treatment appears to be the best choice for most men over 60, particularly those who already have another life-shortening disease that is likely to kill them within the next ten years. They note that further studies are needed. Follow-up for five to ten more years is needed to see if the untreated group still has the same death rate as the treated groups, since most cases of prostate cancer grow very slowly and most patients die of something else before the prostate cancer can kill them. Other studies show that prostate cancer is more likely to spread in younger men who are diagnosed before their 60th birthday and in those whose cells look more malignant under a microscope (Gleason score greater than 7).
Summary of Current Recommendations
Most men who have prostate cancer will not die from it. Each case must be treated individually, but men newly diagnosed with prostate cancer who have less than 10 years of life expectancy because of other conditions (such as heart disease or diabetes), and have low Gleason scores and no evidence of cancer spread, are often advised to follow a program of watchful waiting. Surgical and radiation treatments can have serious side effects, so for some men the treatment can cause more problems than the disease. Once prostate cancer has spread to other parts of the body, a combination of surgery and radiation significantly increases survival and reduces side effects.