According to a new study from the universities of Bristol and Oxford, delaying treatment for prostate cancer does not increase the risk of mortality.
The study found that active monitoring of prostate cancer led to the same 15-year survival rates as treatment with radiotherapy or surgery. Men on an active monitoring programme for prostate cancer were more likely to see the disease progress or spread than patients who received radiotherapy treatment for prostate cancer, but this did not reduce their chances of survival.
The researchers also found that radiotherapy and surgery negatively affected urinary and sexual function for up to 12 years, which is longer than previously thought.
The study, titled ‘Fifteen-Year Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer‘, has been published in the New England Journal of Medicine.
Treatment for prostate cancer should be calm and considered
These findings proved to the researchers that treatment for low and intermediate-risk localised prostate cancer should not be rushed.
“It’s clear that, unlike many other cancers, a diagnosis of prostate cancer should not be a cause for panic or rushed decision-making. 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 lead investigator, Professor Freddie Hamdy from the University of Oxford.
The trial was the first to comprehensively examine three major treatment options for localised prostate cancer. These were: active monitoring, surgery, and radiotherapy with hormones.
The study assessed 1,643 men aged 50-69 diagnosed with prostate cancer between 1999 and 2009. Each of these men was randomly assigned one of the three treatment options. Each participant was followed for an average of 15 years while their mortality rates, cancer progression and spread, and quality of life were measured.
Around 97% of the participants survived up to 15 years after their prostate cancer diagnosis. Around 25% of the men in the trial had not received invasive treatment for prostate cancer after 15 years.
Surgery and radiotherapy led to long-term health issues
Patients from all three groups reported similar outcomes regarding their quality of life and general physical and mental health. However, men who received surgery or radiotherapy reported an impact on urinary, bowel and sexual function for a surprisingly long time.
Previous research had found that men whose cancer was actively monitored were twice as likely to see disease progression or metastasise than those in the other groups. It was assumed this would correlate with lower survival rates; however, the results of this study show this not to be true.
“This is very good news. Most men with localised prostate cancer are likely to live for a long time, whether or not they receive invasive treatment and whether or not their disease has spread, so a quick decision for treatment is unnecessary and could cause harm,” said Professor Hamdy.
“It’s also now clear that a small group of men with the aggressive disease cannot benefit from any of the current treatments, however early these are given. We need to both improve our ability to identify these cases and our ability to treat them,” he added.
The study also suggested that current methods of predicting the rate of cancer progression are flawed. Initially, all participants in the study were diagnosed with localised cancer, 77% of whom were deemed low risk. When the participants were reassessed using modern methods, a significantly larger number were deemed to be at intermediate risk. The researchers also found that in around 30% of the patients, the disease had spread beyond the prostate, meaning that the participants in the study were at higher risk than previously thought. Despite these new findings, mortality levels remained low in men, proving that delayed treatment for prostate cancer does not affect the likelihood of survival.
“The fact that the greater progression of disease seen under active monitoring didn’t translate into higher mortality will be surprising and encouraging to urologists and patients. Active monitoring and biopsy protocols today are much more advanced than at the time this trial was conducted, so it’s possible we could improve on these outcomes still further. It’s an important message for patients that delaying treatment is safe, especially as that means delaying side effects as well,” concluded Professor Peter Albers, chair of the EAU’s Scientific Congress Office and a urologist at Düsseldorf University.
