Doctors have known for some time that men with a potentially aggressive form of early-stage prostate cancer may live longer if they get hormone therapy along with radiation treatments. Standard treatment has called for 3 years of hormone therapy, but a new study suggests just 6 months may be enough to improve a man's odds.

Researchers from Boston's Brigham and Women's Hospital and Dana-Farber Cancer Institute found that men treated with 6 months of androgen suppression (hormone) therapy in addition to radiation fared better than men treated with radiation alone. They reported their results in the Journal of the American Medical Association (Vol. 292, No.7: 821-827).

The finding is important because long-term androgen suppression, though beneficial in men at high risk of recurrence, can have severe side effects including bone density and muscle loss, impotence, anemia, hot flashes, breast enlargement, and memory impairment. A shorter course of hormone treatment might offer better survival with fewer of these side effects.

"These results should prompt physicians evaluating treatment options to prescribe 6 months of hormone therapy as opposed to a 3-year regimen," said lead study author Anthony D'Amico, MD, PhD, a radiation oncologist at Dana-Farber and Brigham and Women's Hospital, and professor of radiation oncology at Harvard Medical School.

D'Amico and his colleagues studied 206 men with localized prostate cancer who appeared to be at high risk of having the cancer spread or return, either because of a high PSA score, a high Gleason score, or other characteristics. Half the men were assigned to receive 2 months of external beam radiation therapy to the prostate; the rest were given the same course of radiation, plus 6 months of androgen suppression therapy.

Men treated only with radiation were more likely to have a recurrence of their prostate cancer. After more than 4 years of follow-up, 6 men who received only radiation therapy had died of prostate cancer, while none of the men who received hormone therapy plus radiation had died of prostate cancer.

The survival benefits of the 6-month hormone treatment were similar to those seen in men who receive long-term hormone therapy, said Theodore L. DeWeese, MD, chairman of the department of radiation oncology and molecular radiation science at Johns Hopkins University School of Medicine. In an editorial accompanying the study, he called the findings "exciting and provocative" and said a short course of androgen suppression therapy might be a "very reasonable option" for some patients.

But that doesn't mean this treatment option is right for all patients, he noted. Men with different disease characteristics may still need a longer course of hormone therapy to see survival advantages. Because the study only looked at men with cancer that didn’t extend outside of the prostate, its results can't be extrapolated to other types of patients.

There are also still questions about the impact of side effects from the shorter hormone treatment, DeWeese said.

In the study, rates of incontinence, rectal bleeding, diarrhea, and blood in the urine were similar among the 2 groups of men. Only impotence and breast enlargement were worse in men receiving the hormone therapy. But the researchers did not ask men how these problems affected their quality of life. Without a systematic assessment of the impact of these side effects, it's difficult to weigh the risks of treatment against the benefits, DeWeese said.

In addition, the radiation dose used in the study was relatively low, DeWeese said. Modern radiation techniques now allow for higher radiation doses to be used. Could a higher dose improve survival, even without additional hormone therapy? D'Amico himself raised this question as a topic for further study.

Because of these questions, DeWeese says it's too soon to consider this treatment approach a new standard of care, though it is a promising option.