A surgeon sitting in front of screens of a Focal One device performs a robot-assisted prostate tumorectomy using ultrasound imaging on April 10, 2014 at the Edouard Herriot hospital in Lyon, center France. Focal One is the first robotic HIFU (high intensity focused ultrasound) device dedicated to the focal approach for prostate cancer therapy. According to EDAP TMS SA, a leader in therapeutic ultrasound, it combines the three essential components to efficiently perform a focal treatment: state-of-the-art imaging to localized tumors with the use of magnetic resonance imaging (MRI) combined with real-time ultrasound, utmost precision of robotic HIFU treatment focused only on identified targeted cancer areas, and immediate feedback on treatment efficacy utilizing Contrast-Enhanced Ultrasound Imaging. AFP PHOTO / JEFF PACHOUD        (Photo credit should read JEFF PACHOUD/AFP/Getty Images)
What is prostate cancer?
01:21 - Source: CNN
CNN  — 

Most men who are diagnosed with prostate cancer can delay or avoid harsh treatments without harming their chances of survival, according to new results from a long-running study in the United Kingdom.

Men in the study who partnered with their doctors to keep a close eye on their low- to intermediate-risk prostate tumors – a strategy called surveillance or active monitoring – slashed their risk of the life-altering complications such as incontinence and erectile dysfunction that can follow aggressive treatment for the disease, but they were no more likely to die of their cancers than men who had surgery to remove their prostate or who were treated with hormone blockers and radiation.

“The good news is that if you’re diagnosed with prostate cancer, don’t panic, and take your time to make a decision” about how to proceed, said lead study author Dr. Freddie Hamdy, professor of surgery and urology at the University of Oxford.

Other experts who were not involved in the research agreed that the study was reassuring for men who are diagnosed with prostate cancer and their doctors.

“When men are carefully evaluated and their risk assessed, you can delay or avoid treatment without missing the chance to cure in a large fraction of patients,” said Dr. Bruce Trock, a professor of urology, epidemiology and oncology at Johns Hopkins University.

The findings do not apply to men who have prostate cancers that are scored through testing to be high-risk and high-grade. These aggressive cancers, which account for about 15% of all prostate cancer diagnoses, still need prompt treatment, Hamdy said.

For others, however, the study adds to a growing body of evidence showing that surveillance of prostate cancers is often the right thing to do.

“What I take away from this is the safety of doing active monitoring in patients,” said Dr. Samuel Haywood, a urologic oncologist at the Cleveland Clinic in Ohio, who reviewed the study, but was not involved in the research.

Results from the study were presented on Saturday at the European Association of Urology annual conference in Milan, Italy. Two studies on the data were also published in the New England Journal of Medicine and a companion journal, NEJM Evidence.

A common cancer that’s often low-risk

Prostate cancer is the second most common cancer in men in the United States, behind non-melanoma skin cancers. About 11% – or 1 in 9 – American men will be diagnosed with prostate cancer in their lifetime, and overall, about 2.5% – or 1 in 41 – will die from it, according to the National Cancer Institute. About $10 billion is spent treating prostate cancer in the US each year.

Most prostate cancers grow very slowly. It typically takes at least 10 years for a tumor confined to the prostate to cause significant symptoms.

The study, which has been running for more than two decades, confirms what many doctors and researchers have come to realize in the interim: The majority of prostate cancers picked up by blood tests that measure levels of a protein called prostate-specific antigen, or PSA, will not harm men during their lifetimes and don’t require treatment.

Dr. Oliver Sartor, medical director of the Tulane Cancer Center, said men should understand that a lot has changed over time, and doctors have refined their approach to diagnosis since the study began in 1999.

“I wanted to make clear that the way these patients are screened and biopsied and randomized is very, very different than how these same patients might be screened, biopsied and randomized today,” said Sartor, who wrote an editorial on the study but was not involved in the research.

He says the men included in the study were in the earliest stages of their cancer and were mostly low-risk.

Now, he says, doctors have more tools, including MRI imaging and genetic tests that can help guide treatment and minimize overdiagnosis.

The study authors say that to assuage concerns that their