Surprise Finding: Increased Health Risks With Intermittent ADT

Recent research suggests that older men on intermittent androgen deprivation therapy (ADT) for prostate cancer are at higher risk for certain adverse events.

Androgens are important hormones for men. Unfortunately, they can also spur the growth and spread of prostate cancer cells. The goal of ADT is to reduce the amount of androgens in the body, cutting off the cancer’s fuel supply.

While ADT is effective, it does have side effects, including sexual problems, osteoporosis, fatigue, increased cholesterol, and anemia.

Sometimes, ADT is given on an intermittent basis. Men have treatment for a certain period of time, take a break, and then return to treatment.

Experts hypothesized that giving ADT this way could reduce the impact of side effects. However, the new study, published online last December in JAMA Oncology, had some surprising results.

The research team looked at data from 1,134 elderly men with metastatic prostate cancer. The cancer cells had spread from the prostate to other parts of the body. The men’s median age was 71 years. Some men underwent intermittent ADT while the rest had continuous therapy.

Next, the scientists studied the incidence of five types of adverse events over ten years. They found that incident rates for hormonal issues, sexual dysfunction, dementia and depression, and acute kidney injury did not differ much between the groups.

However, the men on intermittent ADT did have a higher incidence of ischemia (poor blood supply to an organ) and thrombosis (formation of blood clots). Their rate was 33% compared to 24% for the men on continuous ADT.

The study authors recommended that doctors be cautious when considering intermittent ADT in elderly men.

Resources

American Cancer Society

“Hormone (androgen deprivation) therapy for prostate cancer”

(Last revised: March 12, 2015)

http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-treating-hormone-therapy

JAMA Oncology

Hershman, Dawn L. MD, MS, et al.

“Adverse Health Events Following Intermittent and Continuous Androgen Deprivation in Patients With Metastatic Prostate Cancer”

(Abstract. Published online: December 23, 2015)

http://oncology.jamanetwork.com/article.aspx?articleid=2476246

Medscape Medical News

Mulcahy, Nick

“Long-term Toxicity Surprise With ADT for Prostate Cancer”

(January 6, 2016)

http://www.medscape.com/viewarticle/856802