Risks of Adverse Effects Lower With Surgical Castration Vs. Chemical Castration for Metastatic Prostate Cancer
Surgical castration via resection of the testicles (orchiectomy) for metastatic prostate cancer (mPCa) is associated with lower risks for adverse effects compared with medical castration via gonadotropin-releasing hormone agonist (GnRHa) therapy, according to a report published in JAMA Oncology (doi:10.1001/jamaoncol.2015.4917).
Androgen-deprivation therapy (ADT) achieved through surgical or medical castration has been a cornerstone in the management of mPCa for the last 50 years. Bilateral orchiectomy, however, has been nearly eliminated from use in the United States because of cosmetic and psychological concerns.
The researchers compared the adverse effects of GnRHa with those of bilateral orchiectomy in 3295 men with mPCa, age 66 years or older, between 1995 and 2009. The authors analyzed 6 major adverse effects (any fractures, peripheral artery disease, venous thromboembolism, cardiac-related complications, diabetes, and cognitive disorders) based on their impact on patient quality of life, the potential for increased health care costs, and on a previously described association with ADT use.
Of the 3295 men, 87% (n=2866) were treated with GnRHa and 13% (n=429) were treated with orchiectomy. Overall 3-year survival was 46% for GnRHa treatment and 39% for orchiectomy.
Study findings show surgical castration is associated with lower risks for any fractures, peripheral artery disease, and cardiac-related complications compared with medical castration. No statistically significant difference was found between orchiectomy and GnRHa therapy for diabetes and cognitive disorders.
Men treated with GnRHa therapy for 35 months or more were at the greatest risk of experiencing any fracture, peripheral artery disease, venous thromboembolism, cardiac-related complications, and diabetes, according to the study results.
The authors note limitations to the study, primarily its retrospective design which relies on historical data.
"In some patients who need permanent androgen suppression, surgical castration may represent a suitable alternative to GnRHa. However, other considerations must be contemplated when deciding between medical or surgical castration (ie, young age, intermittent ADT)," the study concluded.