Men with high-risk prostate cancer fare better when they are treated with at least 12 months of hormone reduction therapy rather than with a shorter duration of treatment, new research suggests. This holds true regardless of how fast growing or advanced the cancer is.

Androgen deprivation therapy involves lowering levels of male hormones, such as testosterone, in the body in an effort to block or slow the growth of prostate cancer. Androgen deprivation therapy is most commonly achieved with medications, but it can also be produced by removing the testes.

Previous reports have suggested a survival benefit with long-term androgen deprivation therapy, but it was unclear if this applied to all patients or only those with fast-growing cancers, lead author Dr. Eric Berthelet, from the British Columbia Cancer Agency (BCCA) in Victoria, Canada, and colleagues note in the International Journal of Radiation Oncology, Biology, Physics.

The study involved 307 patients who were treated with radiation therapy and entered in the Prostate Cancer Outcomes Initiative database of the BCCA.

Roughly half of the patients received short-term androgen deprivation therapy, defined as less than 12 months, and half received therapy for longer durations. The groups were comparable in terms of tumor aggressiveness and disease stage, the authors note.

The patients were followed for around 47 months. The typical duration of treatment in the short-term group was 6 months, whereas the duration in the long-term group was 26 months.

On follow-up, 63 percent of long-term therapy patients had no apparent disease compared with just 37 percent of short-term therapy patients.

Moreover, the 5-year survival rate in the long-term group was 88 percent, significantly higher than the 75 percent rate seen in the short-term group.

The study shows that long-term androgen deprivation therapy used along with radiation treatment improves survival rates for high-risk patients, regardless of the cancer’s aggressiveness or disease stage, Berthelet concluded.

SOURCE: International Journal of Radiation Oncology, Biology, Physics. November 1, 2005.