Chicago ? Doctors are reporting a key advance in treating men with cancer that has started to spread beyond the prostate: survival is significantly better if radiation is added to standard hormone treatments.

Results of the study were given Sunday at a cancer conference, where other research showed that an experimental drug boosted survival for women with very advanced breast cancer. The drug is being reviewed by the federal Food and Drug Administration.

The prostate study has the potential to change care right away. About 20 percent of the nearly 200,000 men diagnosed with the disease each year in the United States are like those in the study — with cancer that has spread to the area around the prostate.