LONDON — Treating advanced prostate cancer with radiation and hormone-blocking drugs cut the death rate in half in a study of Scandinavian men, researchers report.

In the United States, the combination has been standard care since the 1990s.

But in Europe, many doctors have avoided the combo treatment and used hormone drugs alone, thinking the pair would be too harsh for most patients.

Scandinavian researchers tracked 875 men with advanced prostate cancer in Denmark, Norway and Sweden.

About half were given hormone-blocking drugs while the other half got the same treatment plus radiation. The drugs block production of testosterone, which feeds cancer cells.

After nearly eight years, 79 men in the hormone only group had died of prostate cancer, compared to 37 in the group that had hormone therapy plus radiation.

Adding radiation to patients' treatment did come at a cost. After five years, men receiving hormones and radiation reported higher rates of side effects including fatigue, insomnia, and sexual problems.