More Prostate Cancers Are Being Diagnosed at a Later Stage
While men can take solace in a new government report that shows prostate cancer cases have been declining overall in the past two decades, the same analysis finds that the opposite is true for advanced prostate cancer cases.
In fact, the number of cases of cancer that had already spread from the prostate to other parts of the body doubled between 2003 and 2017, going from 4% to 8%, according to researchers from the U.S. Centers for Disease Control and Prevention.
"Understanding who gets prostate cancer and what the survival numbers are like could be important for men making prostate cancer screening decisions, providers discussing these decisions with their patients, and for informing recommendations for prostate cancer screening," said lead researcher Dr. David Siegel, from CDC's Division of Cancer Prevention and Control.
Why the spike in advanced prostate cancers? Dr. Anthony D'Amico, a professor of radiation oncology at Harvard Medical School in Boston, said the increase was an inevitable consequence of a 2012 recommendation from the U.S. Preventive Services Task Force against the routine use of prostate cancer screening with the prostate-specific antigen (PSA) test.
"We realized in 2012, when the U.S. Preventive Services Task Force said to stop PSA screening, we would expect that somewhere around 2018 to 2019 that cancer death rates would start to go up, and that about two to three years prior to that, around 2015 to 2016, we would expect to see distant metastases [cancer that has spread] go up because they preceded death by a couple of years," he explained.
That's exactly what this report found, D'Amico noted.
"That trend will continue because the reversal of the recommendation against PSA screening didn't happen until , so it's going to be a couple of years from now before we start to see a plateauing and eventually a decrease in distant disease," he said. "We should have PSA brought back."
While D'Amico said he believes that men should have their PSA level tested, whether an elevated PSA leads to further diagnosis or treatment should be based on a conversation between a man and his urologist.
"We're diagnosing less low-risk cases now, but there's no problem from my perspective in bringing the PSA back, so that the patients with low-risk cancer can have the discussion whether they want treatment or not, knowing what the side effects are, and the patients who need to be cured can be cured," D'Amico said.
Men are getting more metastatic disease and dying, he said. "But because of the reversal of PSA screening, it should come back to where it was, and the only difference is now we're smarter about who to treat and who not to treat," D'Amico said.
The CDC study also delved into racial differences for prostate cancer survival. The researchers found that five-year survival was highest among Asian/Pacific Islanders (42%), followed by Hispanics (37%), American Indian/Alaska Natives (32%), Black men (32%), and white men (29%).
Understanding prostate cancer rates and survival can help guide treatment and survivor care planning, Siegel said.
This study did not look at PSA testing trends, but past studies have noted decreasing use of PSA testing, Siegel acknowledged. "There are a lot of factors, including decreases in PSA testing, that might contribute to the incidence trends we reported in this study."
The findings were published Oct. 16 in the CDC's Morbidity and Mortality Weekly Report.
For more on PSA tests, see the U.S. Centers for Disease Control and Prevention.
SOURCES: David Siegel, M.D., M.P.H., Division of Cancer Prevention and Control, U.S. Centers for Disease Control and Prevention; Anthony D'Amico, M.D., Ph.D., professor, radiation oncology, Harvard Medical School, Boston; Morbidity and Mortality Weekly Report, Oct. 16, 2020