Men who undergo prostate cancer treatment face a greatly increased risk of life-altering, long-term complications, a new study finds.

Surgery for prostate cancers increases a man’s risk of urinary or sexual complications more than sevenfold, researchers reported Nov. 7 in the journal JAMA Oncology.

Meanwhile, radiation therapy, the other major treatment option, causes a threefold increase in a man’s risk of similar complications or bladder cancer, researchers discovered.

Many men might opt out of prostate cancer screening if they knew these potential risks, researchers argue.

“This study throws down a major gauntlet to all physicians to give patients this information before they even begin the process of drawing a PSA test,” said senior researcher Dr. Ian Thompson Jr., a urologist with the University of Texas Health Science Center at San Antonio.

A PSA test measures the blood level of a protein called prostate-specific antigen. Men with rising PSA levels are at greater risk of prostate cancer.

About 30 million U.S. men are in the age range (55 to 69) recommended to discuss PSA testing with their doctor, researchers said in background notes.

Making an informed decision about PSA testing requires that men understand the magnitude of the risks and benefits of screening, researchers said.

For this study, researchers analyzed data for more than 29,000 men who participated in one of two large National Cancer Institute studies aimed at preventing prostate cancer.

The team found that more than 3,900 of these men had been diagnosed with prostate cancer, including 655 treated with surgery and 1,056 who received radiation therapy.

The rest of the men had opted for active surveillance of their prostate cancer, given that the cancer tends to grow slowly.

Researchers examined Medicare claims data for 10 potential complications related to prostate cancer treatment, including erectile dysfunction, incontinence and bladder cancer.

Men in the prostate surgery group had a more than six times greater risk of having at least one of these complications within 12 years of their procedure, compared to those who weren’t treated, results show.

The 12-year risk of complications from radiation therapy was three times greater than foregoing treatment, researchers noted.

“Past studies of prostate cancer treatment complications have had small sample sizes, limited follow-up or the absence of a valid control group,” lead researcher Joseph Unger, an associate professor at Fred Hutch Cancer Center, said in a news release.

“Our study is distinguished by long follow-up, out to 12 years, looking at a broad spectrum of key complications,” Unger added. “Critically, we were able to compare treated men to a representative control group of untreated men, which prior studies have not included.”