LONDON — More men with prostate cancer could afford to delay their treatment, a decades-long study has found, suggesting that active monitoring by health-care professionals is an equally valid — and less harsh — option.
More aggressive treatment helped slow progression of the disease, but did not lower the men’s overall risk of dying of the disease. The authors say this finding suggests that “more aggressive therapy can result in more harm than good” — because the side effects of those treatments can be debilitating to patients, and may not pay off in the end.
That is “very good news for patients,” said Freddie Hamdy, a professor of surgery and urology at the University of Oxford and lead author of the study. It means that more men could afford to delay aggressive treatments that are likely to leave them with lasting side effects, as long as they are carefully monitored for changes in their condition.
That kind of monitoring is already offered to low-risk prostate cancer patients in the United Kingdom and the United States, but this study suggests that it “can be extended safely to intermediate-risk disease,” Hamdy said. It could provide some hope to people affected by prostate cancer, which is the fourth-most prevalent type of cancer worldwide.
As part of the study, which was funded by the British government, more than 80,000 men between 50 and 69 were screened for prostate cancer between 1999 and 2009. More than 2,600 were diagnosed with the disease, and 1,643 were enrolled in the trial.
The men were at low or intermediate risk from their disease, and the authors stressed that their findings do not apply to men at high risk. “High-risk patients need quick and aggressive treatments,” Hamdy said.
The researchers split the men in the cohort into three groups that were monitored over time or treated with radiotherapy or prostatectomy, a surgical procedure to remove all or parts of a patient’s prostate. The goal was to measure and compare the effectiveness of each treatment.
At a median of 15 years post-diagnosis, the men were given a follow-up to see how they were faring. Fewer than 3 percent had died of prostate cancer, and the odds were similar for each treatment group. For example, 3.1 percent of the deaths came among men in the active-monitoring group, while 2.9 percent were among men who received radiotherapy.
Without treatment, men in the active-monitoring group were nearly twice as likely to see their prostate cancer progress and spread — or form what’s known as metastases — than the men in the aggressive treatment groups. But that progression didn’t lead to a higher likelihood of death. This surprised the researchers, according to Hamdy, who said it suggests that “if men develop metastases, that doesn’t necessarily mean they will die of prostate cancer” — though they may die of other causes.
Because prostate cancers typically progress slowly, even if the cancer evolves more quickly under active monitoring, the study’s finding suggests that the long-term deleterious effects of harsh treatment may not be worth it.
Active monitoring, also known as active surveillance, is already used for many low-risk men. It doesn’t mean “doing nothing,” Hamdy said. Patients under active monitoring are tested regularly by a clinician for “any hint that the disease is progressing.” If the cancer is progressing, then the patient may need surgery, radiation or hormone therapy. In the study, most men in the active-monitoring group eventually received some form of more aggressive treatment.
Jenny Donovan, a professor of social medicine at the University of Bristol and co-author of the study, said some men make the decision to undergo aggressive forms of treatment because they do not fully understand that they could delay those treatments without affecting their chances of survival — and some later “regret their decisions.”
In a separate paper, also published Saturday in the same medical journal, the researchers revealed that many men who undergo aggressive treatments report negative side effects that can last up to 12 years. These side effects include urinary leakage and erectile dysfunction. They “come quite soon after treatment but do then last into the long-term,” said Donovan, who argues it is important for patients to consider these effects against the likely benefits of the treatments.
“Now, men diagnosed with localised prostate cancer can use their own values and priorities when making the difficult decisions about which treatment to choose,” Donovan said in a news release.
Overall, the study shows that patients “should not panic if they’re diagnosed with prostate cancer,” Hamdy said. “But if they have high risk, they really need to seek advice and get treated well.”