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One of the most delicate dilemmas with prostate cancer is whether and when men need to undergo radiation therapy after surgery, with its potentially dire side effects, to remove the prostate.
Three new randomized clinical trials – the gold standard study – and a statistical “meta-analysis” of their results now conclude that routine postoperative radiation does not improve results after five years, compared to radiation only when the PSA blood test (prostate -specific antigen) signals a recurrence of cancer. The articles were published in the Lancet and Lancet Oncology last month.
“All surgeons have always struggled with it,” said Alexander Kutikov, a urological oncologist at Fox Chase Cancer Center. “You don’t want to over-treat, but you don’t want to lose the window of opportunity. These attempts really crystallize out that you can hold back the radiation. It changed my practice.”
This change has benefited not only Kutikov’s post-operative patients, but also men like James Boughter, 56, who underwent surgery six years ago.
“We keep an eye on (the PSA) every six months,” said Boughter, a machinist who lives in Honey Brook, Chester County.
Boughter’s PSA was barely detectable about a year ago, but was stable at this low level. Based on the latest research, Kutikov assured Boughton that he could hold back the radiation and hopefully do without it altogether.
“If I had to do radiation, I would definitely do it when it came to cancer. But I’d rather not,” said Boughter of the risk of urinary or other problems.
Claire Vale, a researcher at University College London who led the meta-analysis, said the studies could save many men from overtreatment: “Guidelines and guidelines regarding the standard of treatment for prostate cancer should be updated based on the results.”
Diagnosing and treating prostate cancer involves trade-offs between risk and benefit, from PSA testing to screening for the disease. Current guidelines state that doctors shouldn’t do routine screening without first discussing concerns that it leads to finding and treating tiny cancers that would never have become a threat if left alone.
When cancer is found in the early stages, the gold standard treatment – especially in younger men – is surgical removal of the walnut-sized prostate.
However, studies suggest that up to 40% of men – including Boughter – are at high risk of recurrence despite having surgery. This is because the cancer was aggressive, or some malignant cells escaped during the surgery, or the cancer spread to tissues near the prostate.
Seven previous randomized trials have tried and failed to definitively answer which men, if any, benefit from postoperative radiation rather than waiting for their PSA to rise. Although radiation reduced the risk of recurrence sooner rather than later, it did not improve survival. In addition, some of the studies did not monitor PSA or give radiation until the cancer progressed, or both, making the results difficult to interpret.
According to the authors of an accompanying comment, the new studies also have some possible limitations. For example, one study included men who would not normally receive postoperative radiation due to their favorable risk profile. And the three studies differed in the use of drugs that block the hormones that cause prostate cancer.
“Still, the four studies represent an important step forward and support“ adding radiation only when the cancer comes back, ”wrote Derya Tilki from the University Medical Center Hamburg-Eppendorf in Germany and Anthony V. D’Amico from the Dana Farber Cancer Institute in Germany Boston.
The meta-analysis, which involved 2,153 patients on average for five years, found that 88% of men who withheld radiation did not relapse, compared to 85% who received radiation shortly after surgery. 67% of those who held back did not need radiation up to eight years later.
Urinary incontinence was worse in men with postoperative radiation after one year. And 6% of them had difficulty urinating because a duct called the urethra was damaged, compared with 4% of men who postponed radiation.
“The idea was always that you missed an opportunity,” said Kutikov. “These studies tell me we can hold back with these men, too,” when the risk of recurrence is higher.
Surgery and combination therapy optimize outcomes in aggressive prostate cancer management
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