WASHINGTON (Reuters) - Adding radiation therapy to standard drug treatment can cut in half the death rate from advanced prostate cancer and should become the standard of care globally, Swedish researchers reported on Monday.

Their study of more than 800 prostate cancer patients showed that nearly 24 percent of men who got only standard drugs had died after 10 years, compared with just under 12 percent of men who also got radiation treatment.

Adding radiation does not add too many side-effects, they wrote in the journal Lancet Oncology.

“The quality of life and adverse effect profile is acceptable. We therefore suggest that endocrine treatment plus radiotherapy should be the new standard of care for these patients,” Anders Widmark of Umea University in Sweden and colleagues wrote.

“The results should change current practice, making long-term hormonal therapy plus radical radiotherapy the standard of care for men with locally advanced prostate cancer,” Dr. Chris Parker and Dr. Alex Tan of Britain’s Institute of Cancer Research in Sutton, Surrey, wrote in a commentary.

Prostate cancer is the second-leading cancer killer of men, killing 221,000 every year globally, with 679,000 new cases diagnosed.

It is easily cured in early stages with surgery or radiation. For prostate cancer that has spread, drugs that interfere with cancer-fueling hormones are prescribed.

In the United States, adding radiation therapy is already standard, said Dr. Howard Sandler, chair of Radiation Oncology at Cedars-Sinai Medical Center in Los Angeles and a spokesman for the American Society of Clinical Oncology.

He said health agencies in Europe did not always provide radiation as the standard of care. “A 50 percent reduction in the risk of prostate cancer death is a real clinical benefit,” Sandler said in a telephone interview.

“The radiation therapy that was performed here (in the study) was somewhat simplistic,” Sandler added. “Modern radiation therapy with higher doses, if anything, might magnify the benefits.”