Adverse Effects Greater for Medical vs. Surgical Castration in PCa
Higher risks of several clinically relevant adverse effects compared with surgical castration.
For men with metastatic prostate cancer, gonadotropin-releasing hormone agonist (GnRHa) treatment is associated with more adverse effects than orchiectomy, according to a study published online in JAMA Oncology.
Maxine Sun, MPH, from Brigham and Women's Hospital in Boston, and colleagues conducted a comparative effectiveness analysis of the adverse effects of GnRHa versus bilateral orchiectomy in a population-based cohort of 3,295 men with metastatic prostate cancer. Participants were 66 years or older, selected from the Surveillance, Epidemiology, and End Results Medicare-linked database.
The researchers found that in adjusted analyses, compared with those treated with GnRHa, patients who received a bilateral orchiectomy had significantly lower risks of experiencing any fractures, peripheral arterial disease, and cardiac-related complications (hazard ratios, 0.77, 0.65, and 0.74, respectively). For diabetes and cognitive disorders there was no statistically significant difference between orchiectomy and GnRHa. An increased risk for GnRHa versus orchiectomy was seen for fractures, peripheral arterial disease, venous thromboembolism, cardiac-related complications, and diabetes mellitus (hazard ratios, 1.80, 2.25, 1.52, 1.69, and 1.88, respectively; P ≤ 0.01 for all) in individuals treated with GnRHa for 35 months or more. The mean total expenditures did not differ significantly between GnRHa and orchiectomy at 12 months after prostate cancer diagnosis.
"Gonadotropin-releasing hormone agonist therapy is associated with higher risks of several clinically relevant adverse effects compared with orchiectomy," the authors write.
Two authors disclosed financial ties to the biopharmaceutical industry.
- Sun M, Choueiri TK, Hamnvik OR, et al. Comparison of Gonadotropin-Releasing Hormone Agonists and Orchiectomy. JAMA Oncol. doi:10.1001/jamaoncol.2015.4917.
- Kolinsky M, Rescigno P, de Bono JS. Chemical or Surgical Castration—Is This Still an Important Question? JAMA Oncol. doi:10.1001/jamaoncol.2015.4918.