The rates of PSA screening and early-stage prostate cancer incidence declined through 2013 following a U.S. Preventive Services Task Force (USPSTF) recommendation against routine PSA (prostate specific antigen) screening in primary care.

The study, “Prostate Cancer Incidence Rates 2 Years After the US Preventive Services Task Force Recommendations Against Screening,“ was published in Jama Oncology.

In 2011, recommendations against the routine use of PSA testing in all men were established by the task force. A notable decline in the incidence of early-stage prostate cancer was reported from 2011 to 2012. Now, researchers found that the number of detected cases declined even further through 2013.

“Whether this pattern will lead to a future increase in the diagnosis of distant-stage disease and prostate cancer mortality requires long-term monitoring because of the slow-growing nature of this malignant neoplasm,” study author Ahmedin Jemal, DVM, PhD, vice president of surveillance and health services research at the American Cancer Society, and his colleagues wrote in the report.

The team used SEER (Surveillance, Epidemiology, and End Results) registries of the National Cancer Institute – representing around 28 percent of the U.S population – to evaluate the incidence of early-stage prostate cancer. The results showed a continued decline from 2012 to 2013 in men 50 years or older, although not to the same extent as the year before.

According to USPSTF, the lifetime risk of being affected with prostate cancer is currently estimated at 16 percent, with the malignancy accounting for the most commonly diagnosed non-skin cancer in men in the U.S. Although most of the cases have a good prognosis even without treatment, some are very aggressive.

There is convincing evidence that a substantial percentage of men are “overdiagnosed” with PSA screening and have a tumor that either will not progress or will grow so slowly that it would have remained asymptomatic for the rest of the patient’s life.

Nearly 90 percent of men with PSA-detected prostate cancer in the U.S. require early treatment with surgery, radiation, or androgen deprivation therapy. Of these men, 0.5 percent will die within one month of prostate cancer surgery, and between 1 to 7 percent will have serious complications but will survive. Also, 20 to 30 percent of these men will suffer from urinary incontinence and erectile dysfunction as a consequence of the treatment.

Estimates from the two largest trials suggest overdiagnosis rates of 17 percent to 50 percent for prostate cancer screening. At the same time, there is adequate evidence that there is about one death avoided per 1,000 men screened.

“Hopefully some doctors and patients are starting to realize the true fact, that the benefits of prostate cancer screening are still an uncertainty, while the harms are well proven,” said Dr. Otis Brawley, MD, FACP, chief medical officer of the American Cancer Society. “I hope these data indicate that men are making an informed choice as to whether to be screened and that doctors are respecting that choice.”