Prostate cancer death rates have stopped declining. What should men do?

After falling for two decades, the death rate for prostate cancer has stopped decreasing and the incidence of advanced disease is rising, researchers said Tuesday.

The unwelcome trends roughly coincide with a decline in screening for the disease, the study showed. But the authors say it isn't clear whether reduced screening is responsible.

"We can't say what triggered the change," said Serban Negoita, a data expert at the National Cancer Institute cancer surveillance program and lead author of the report. He added that the report did not try to determine cause and effect and that cancer incidence and death can be affected by many factors.

Alexander Kutikov, a urologic oncologist at Fox Chase Cancer Center, also urged caution.

"It's easy to get whiplash from these numbers and recommendation changes," he said. "We just have to be very clear with our patients that there are harms and benefits to screening. It's important that they get educated."

The new data immediately reignited long-running arguments over the use of screening through prostate-specific antigen (PSA) tests. In 2012, a federal advisory committee discouraged routine use of PSA tests for all men. The U.S. Preventive Services Task Force said too many men were being harmed by aggressive treatment for early stage malignancies that didn't pose a threat.

But this month, citing new data, the task force revised its stance to say that men ages 55 to 69 should make individual decisions on screening after talking to their doctors. The group continued to recommend against screening for men over 70.

On Tuesday, echoing earlier debates, critics of that 2012 recommendation blamed it for the rise in advanced prostate cancer cases. Others disagreed, saying there is no way to know at this point if the two are linked and noting that the new study didn't deal with the significant harms, including sexual dysfunction and incontinence, that can result from surgery and radiation.

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Kutikov is among those who noted that it is far too soon for the 2012 recommendation to be impacting death rates. He also called the recently revised recommendation, which leaves the screening decision up to patients and their doctors, "appropriate."

How to screen for and treat prostate cancer has been hotly debated as doctors and patients try to better balance the potential benefits and downsides of various approaches. While doctors once urged patients to undergo immediate aggressive treatment for early stage malignancies, many now recommend "active surveillance," or close monitoring, for indolent cancers.

Between the revised task force recommendation and the data published Tuesday, experts say that more men are now likely to get screened even if they don't then go on to immediately pursue aggressive treatment.

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Prostate cancer is the most common malignancy in men after skin cancer. An estimated 165,000 men in the United States will be diagnosed with prostate cancer this year and more than 29,000 will die of the disease, according to the American Cancer Society.

The prostate cancer data were released as a companion study to the latest Annual Report to the Nation on the Status of Cancer, a collaborative effort by the cancer institute, the Centers for Disease Control and Prevention, the American Cancer Society, and the North American Association of Central Cancer Registries. Both reports appeared Tuesday in the journal Cancer, which is published by the cancer society.

The annual report found that overall death rates from cancers continue to decline in men, women, and children and in all major racial and ethnic groups. But that overarching trend masks big variations. Five-year survival rates are high for early-stage prostate, breast and colorectal cancer, but much lower for all stages of lung cancer, the report said. And a rise in liver, pancreatic, and uterine cancer is stirring concern.

The prostate cancer report showed that the overall incidence of the disease — which includes all stages — decreased an average of 6.5 percent each year between 2007 and 2014. However, the incidence of disease that has spread from the original tumor to other parts of the body increased between 2010 and 2014. Death rates from prostate cancer, after a long drop, leveled off between 2013 and 2015.

The report said that declines in PSA screening began in 2010 for men 50 to 74 years old and in 2008 for men 75 and older.

Eleni Efstathiou, an oncologist at MD Anderson Cancer Center who disagreed with the original recommendation against PSA tests, said the new data were "no surprise."

"I believe the fact that we loosened up on screening led to more advanced disease upon diagnosis," she said, adding, "What the task force did in 2012, they decided that knowledge is bad, rather than saying knowledge should be met by more knowledge and education."

Stacy Loeb, a urologist at NYU Langone Health who also opposed the task force's 2012 recommendation, said the controversy over screening has created confusion among patients and primary care physicians.

"There is irrefutable evidence that PSA screening has benefits and does reduce advanced disease and death," she said. "But there is also irrefutable evidence that it can lead to downstream harm." Those harms can be mitigated, she said, by the use of active surveillance for early disease.

Otis Brawley, chief medical and scientific officer of the cancer society, said he doesn't believe the 2012 screening recommendation led to the changes in the trends for advanced prostate cancer and death rates.

"It's difficult to look at a population and say that one thing that you did is the cause of something," Brawley said. "A nonscreening recommendation in 2012 would not have affected the mortality rate so quickly."

He said men and their doctors now should focus on the fact that something close to a consensus has emerged among major physician groups and the preventive services task force: The question of PSA testing should be a shared decision by patients and their doctors.

Alexander Krist, a family medicine physician who is vice chairman of the preventive services task force, said it is difficult to link reduced screening to the advanced disease and death rates mentioned in the new report because so many things can affect such trends, including the availability or lack thereof of new treatments.

He also noted that decreases in screening had already begun before the panel's 2012 recommendation and that that report didn't look at the harms that resulted from screening.

Staff writer Marie McCullough contributed to this article.