15-Year Study Finds It’s Safe to Delay Treatment for Low-Risk Prostate Cancer

Most men diagnosed with low-risk prostate cancer can safely delay radiation or surgery without increasing their risk of death due to the cancer, according to research presented at the European Association of Urology (EAU) Congress in Milan and published on March 11 in The New England Journal of Medicine.

The study results showed that although men on active monitoring were more likely to have their cancer advance or spread, they had the same high survival rates — 97 percent after 15 years — compared with men who had radiation or surgery.

“It’s clear that, unlike many other cancers, a diagnosis of prostate cancer should not be a cause for panic or rushed decision making,” said lead author Freddie Hamdy, MD, professor of urology and head of the Nuffield department of surgical sciences at the University of Oxford in England, in a press release.

“Patients and clinicians can and should take their time to weigh up the benefits and possible harms of different treatments, in the knowledge that this will not adversely affect their survival,” said Dr. Hamdy.

“This is a landmark study that was well designed with a large number of patients and a 15-year follow-up,” says Nitin Yerram, MD, co-director of urologic oncology and director of urologic research at Hackensack University Medical Center in New Jersey. “And it’s telling us that surveillance is a really great option for men with low-risk prostate cancer, [since it] resulted in the same mortality rates as surgery and radiation,” says Dr. Yerram, who was not involved in the study.

To Treat or Not to Treat? It’s Complicated

Prostate cancer is the second leading cause of cancer death in American men behind lung cancer, according to the American Cancer Society. Although prostate cancer often grows slowly and is confined to the prostate gland, some types of prostate cancer can be aggressive and spread to other areas in the body, per Mayo Clinic.

There is evidence to support active surveillance and nontreatment of prostate cancer and, at the same time, there is evidence to suggest that some treatments for prostate cancer are important in prolonging survival, says Shawn Dason, MD, a urologic oncologist at The Ohio State University Comprehensive Cancer Center in Columbus.

“This is really the challenge for clinicians in today’s world,” says Dr. Dason, who was not involved in the study. “After assessing the risk level, we need to make sure we’re not overtreating [patients] by potentially giving them treatments that could have urinary or sexual side effects. But in many cases, we will eventually need to treat with radiation and surgery.”

Prostate Cancer Survival Rates Were the Same for Active Monitoring, Radiation, and Surgery

Participants included a total of 1,643 men between 50 to 69 years old from across the United Kingdom who were diagnosed with localized prostate cancer after a PSA blood test between 1999 and 2009. All the men had cancers that had not metastasized or spread to other parts of their bodies, and 77 percent of the participants were considered low-risk at the start of the study.

Low-risk prostate cancer — also called localized prostate cancer because it’s found only in the prostate — often grows very slowly or doesn’t grow at all, according to InformedHealth.org.

When they joined, the men were randomly assigned to one of three treatment groups:

• active monitoring with regular blood tests to keep an eye on PSA levels
• radiotherapy (radiation), which used hormone-blockers and radiation to shrink tumors
• prostatectomy, or surgery to remove the prostate

Men in the active monitoring group were more likely to have their cancer progress and more likely to have it spread compared with the other groups. If the cancers progressed to the point that they needed more treatment, these men could change groups.

In addition to the 97 percent survival rate found in all groups, close to 1 in 4 men in the active monitoring had still not had any invasive treatment for their cancer after 15 years.

The high survival rate among the active surveillance group is also surprising because about 30 percent of the men in the study actually had intermediate-risk prostate cancer, which was only revealed after their original health data was reanalyzed later using modern tests that weren’t available when the study began.

This is a seminal study in the field, says Dason, because there are very few studies of this size and this length of follow up. “These findings show that it’s likely safe to monitor these patients until their cancer progresses and then treat them at the time of progression. It really supports active surveillance for a lot of these patients,” he says.

“Patients and doctors now have the necessary information on the long-lasting side effects of treatments to better understand the trade-offs between their benefits and harms,” said coauthor Jenny Donovan, PhD, professor at the University of Bristol in England, in a press release.

Since survival was the same for all three options, men diagnosed with localized prostate cancer can use their own values and priorities when making the difficult decisions about which treatment to choose, said Dr. Donovan.

Advancements in Imaging and Biopsies Make Surveillance Even More Effective

“When somebody is diagnosed with low-risk prostate cancer and it’s decided that you don’t need to treat this right away, [doctors need to] very closely follow them to look for progression — that’s called active surveillance,” says Dason.

It’s worth noting that active monitoring as it was performed in this trial has improved greatly in the past 15 years, according to an accompanying editorial in The New England Journal of Medicine. When this study started, researchers didn’t have all the tools available today, such as safer biopsies and better imaging, including prostate MRI, notes Dason.

About 9 percent of men in the active monitoring group had their cancer metastasize, compared with 5 percent in the two other groups. Those numbers would likely be smaller if currently available monitoring tools were used, noted the editorial.

“Nowadays, active surveillance for prostate cancer could include PSA (prostate-specific antigen) testing every six months, MRI testing every two years, repeat biopsies, maybe up front at a year after diagnosis, and then every three to five years,” says Dason.

Prostate Cancer Treatment May Affect Urinary and Sexual Function

Patients from all three groups reported similar overall quality of life, in terms of their general mental and physical health, according to the findings.

Investigators found that the negative impacts of radiation and surgery on urinary and sexual function persist much longer than previously thought — up to 12 years in some cases.

There’s no doubt that there are urinary and impotence issues following both radiation and surgery, says Yerram. “But as men get older, these issues can occur even without treatment for prostate cancer, and so it’s hard to tease out the effects of the treatments,” he says.

By the end of the study, nearly all the men reported low sexual function, but their patterns of decline were different depending on their prostate cancer treatment, said Donovan.

The Bottom Line: Surveillance Is a Safe Option for Many, but Not All, Men With Prostate Cancer

Although these findings support active surveillance, it’s important not to put all people with prostate cancer in the same bucket, says Yerram. “We need to have individual discussions to see the best treatment plan for them,” he says.

There are also more men being diagnosed with more advanced prostate cancer in the last few years, says Yerram. “These are men with high-risk prostate cancer — prostate cancer that we’re concerned might have spread based on some of our testing. It would be a mistake to think that these results apply to this group, because that wasn’t the type of patient who was studied here,” he says.

Those patients will almost certainly benefit from treatment both to improve their quality of life and to extend their lifespan, says Yerram.