Shorter ADT regimen improved quality of life among men with high-risk prostate cancer

Men with high-risk prostate cancer who underwent treatment with radiotherapy plus 18 months of androgen deprivation therapy demonstrated improved testosterone recovery compared with those who underwent radiotherapy plus 36 months of androgen deprivation, according to results of a randomized phase 3 study presented at the ASTRO Annual Meeting.

Perspective from Colleen A.F. Lawton, MD, FASTRO

“Those who recover normal testosterone value have better quality of life,” Abdenour Nabid, MD, radiation oncologist at Centre Hospitalier Universitaire de Sherbrooke and associate professor at the University of Sherbrooke in Quebec, Canada, said during a press conference. “A higher proportion of patients [assigned 18 months of androgen deprivation therapy] recovered normal testosterone value, and they did so in a much shorter time. This was done without any apparent detriment to long-term outcomes.”

Abdenour Nabid

Initial results from the multicenter trial, presented at the Genitourinary Cancers Symposium last year, showed comparable OS between those assigned 18 months of androgen deprivation therapy [ADT] and those assigned a 36-month ADT regimen.

In the current analysis, Nabid and colleagues evaluated quality of life after testosterone recovery.

The trial included 561 patients with high-risk prostate cancer. Researchers randomly assigned 289 patients to 18 months of ADT plus radiotherapy. The other 272 underwent 36 months of ADT plus radiotherapy. Radiotherapy for all patients began 4 months after initiation of ADT.

After a median follow-up of 84 months, 161 (55.7%) of patients in the 18-month ADT group had recovered normal testosterone levels, compared with 122 (44.9%) of those assigned 36 months of ADT. Patients in the 18-month ADT group experienced shorter median time to testosterone recovery (47.2 months; range, 40.1-54.3) than those in the 36-month ADT group (73.2 months; range, 58.3-88.2).

Nabid and colleagues measured quality of life by the validated EORTC30 and PR25 questionnaires. The two questionnaires included a combined 55 items, which were grouped into 21 scales.

Patients completed questionnaires prior to treatment, every 6 months during ADT, 4 months after completion of ADT, and again once per year for 5 years post-treatment. More than 9,300 questionnaires were included in the final analysis.

Results showed men who recovered normal testosterone reported better quality of life than those who did not. The differences on 26 of the 55 questionnaire items, as well as 12 of the 21 scales, were statistically significant, researchers wrote.

“In high-risk prostate cancer, the current guideline for ADT duration is between 2 and 3 years,” Nabid said in a press release. “Because of improvement in testosterone recovery and quality of life, a good first step could be to choose ADT for 2 years.”

For more information:

Nabid A. Abstract #24. Presented at: ASTRO Annual Meeting; Sept. 14-17, 2014; San Francisco.

Disclosure: The study was funded by AstraZeneca. The researchers report a research grant from AstraZeneca, as well as honoraria and travel expenses from Sanofi.

Perspective

Colleen A.F. Lawton, MD, FASTRO

When we talk about short duration of hormone therapy, it’s typically either 4 months or 6 months. Defining “long duration” has been the challenge. If you believe the data from Western Europe, it is 36 months. If you believe the data from the United States, it is 28 months. I do think 18 months is potentially our new long-term hormone therapy option. Going forward, the question will be: Can we shorten it from there? The data from [Nabid and colleagues] show if you go from 36 months to 18 months, you improve quality of life but maintain quantity of life. At some point, we are going to cross the divide. There have been multiple studies looking at short-term and long-term hormone therapy and they all have been in favor of long term for our patients with the most aggressive prostate cancers. But is long term 18 months? Is it 24 months? We know 18 months is better than 36 months, but could it be shorter than that? That is data we have yet to see.

Colleen A.F. Lawton, MD, FASTRO

Professor of radiation oncology

Vice chair, Department of Radiation Oncology

Medical College of Wisconsin

Disclosures: Lawton reports no relevant financial disclosures.