Most Aggressive Form of Prostate Cancer on the Rise

Doctors treat a prostate cancer patient. A new study suggests the most aggressive form of the disease is on the rise. Baz Ratner/REUTERS

For decades, experts have said the diagnostic used to screen patients for prostate cancer is too unreliable to use routinely because it produces high rates of false positives and often results in additional unnecessary and invasive tests, as well as overtreatment. However, a new study suggests efforts to limit the use of the prostate-specific antigen (PSA) test may be partially responsible for a rise in incidences of the most aggressive form of the disease.

The study, published Tuesday in Prostate Cancer and Prostatic Diseases, suggests doctors may want to reconsider their approach to screening and monitoring the disease, since rates of metastatic prostate cancer have increased 72 percent in the past decade. The researchers also found rates of the this form the disease surged 92 percent in men 55 to 69 years old compared with men in other groups.

"These recent trends highlight the continued need for nationwide refinement in prostate cancer screening and treatment to prevent the morbidity and mortality associated with metastatic prostate cancer," the researchers write in the study.

For the study, the researchers looked at data from the National Cancer Database (a registry jointly sponsored by the American College of Surgeons and the American Cancer Society). The data accounted for more than 700,000 men who had received a diagnosis of prostate cancer between 2004 and 2013.

The researchers say addressing this trend should be a health care priority, since treating late-stage prostate cancer is far costlier than PSA testing and additional screenings measures, such as biopsy, that are used to confirm a prostate cancer diagnosis.

Some experts suggest this form of prostate cancer is also becoming more aggressive, which is contributing to the rising number of cases. Others say it could be a combination of both factors.

PSA testing provides a measure of proteins produced by cells of the prostate gland. An elevated level of these proteins is typically found in men with prostate cancer. However, the test can be misleading because the protein level often rises as men age.

In 2008 and 2012, the U.S. Preventive Services Task Force—an expert panel composed of independent physicians and supported by the U.S. Department of Health and Human Services—updated its PSA testing guidelines to promote a more judicious use of the test. Doctors have been quick to pick up on these recommendations.

The task force drew up these guidelines after reviewing current research that suggests only about one in every 1,000 men who opt for PSA testing averts death because of this screening. They also found that only one in about every 3,000 men tested dies from prostate cancer complications and many more are harmed due to subsequent tests performed as a result of PSA testing. Biopsy—used to confirm and stage a prostate cancer diagnosis—poses short- and long-term risk for urinary and sexual dysfunction and can cause infection.

Most men diagnosed with cases of prostate cancer don't require immediate treatment. Instead, physicians are likely to recommend "watchful waiting," meaning the cancer is monitored and only treated if it progresses significantly.

Early-stage prostate cancer has a survival rate of about 100 percent, but a late-stage metastatic form of the disease has only a five-year survival rate of about 28 percent, according to the American Cancer Society.

After skin cancer, prostate cancer is the most commonly diagnosed cancer among men in the U.S.