This article is more than 5 years old. Information may no longer be current.
Orchiectomy may confer better safety profile for metastatic prostate cancer
Click Here to Manage Email Alerts
Surgical castration appeared associated with fewer clinically relevant adverse events compared with medical castration with gonadotropin-releasing hormone agonist therapy among men with metastatic prostate cancer, according to results of a population-based cohort study.
“Androgen-deprivation therapy achieved with surgical or medical castration, leading to a disruption of the hypothalamic-pituitary-gonadal axis, has been a cornerstone in the management of metastatic prostate cancer for the past half-century,” Quoc-Dien Trinh, MD, associate surgeon at Brigham and Women’s Hospital and Dana-Farber Cancer Institute, as well as associate professor of medicine at Harvard Medical School, and colleagues wrote. “In contemporary years, cosmetic and psychological concerns have nearly eliminated the use of bilateral orchiectomy in the U.S., even for patients who will need lifelong ADT. However, one of the publications that first noted an increased risk for cardiac events on gonadotropin-releasing hormone agonists (GnRHa) indirectly observed that patients who received orchiectomy may not have the same increased risk for cardiac events.”
Quoc-Dien Trinh
Thus, Trinh and colleagues sought to compare the adverse events associated with the two treatment options among men with metastatic prostate cancer.
The researchers used the SEER–Medicare linked database to identify 3,295 men (median age, 78 years; range, 72-83) aged 66 years or older diagnosed with metastatic prostate cancer between January 1995 and December 2009. The men received GnRHa (n = 2,866) or underwent bilateral orchiectomy (n = 429).
The incidence of six clinically relevant adverse events — any fractures, peripheral artery disease, venous thromboembolism (VTE), cardiac-related complications, diabetes and cognitive disorders — served as the primary endpoint.
Overall, men treated with orchiectomy appeared at lower risk for any fractures (HR = 0.77; 95% CI, 0.62-0.94), peripheral arterial disease (HR = 0.65; 95% CI, 0.49-0.87) and cardiac-related complications (HR = 0.74; 95% CI, 0.58-0.94).
There appeared to be no statistically significant differences in the incidence of diabetes or cognitive disorders between the orchiectomy and GnRHa cohorts.
Researchers also conducted secondary analyses to determine the effect of increasing duration of GnRHa treatment.
Patients treated with GnRHa for 35 months or longer experienced an increased risk for fractures (HR = 1.8; 95% CI, 1.45-2.24), peripheral arterial disease (HR = 2.25; 95% CI, 1.67-3.05), VTE (HR = 1.52; 95% CI, 1.09-2.12), cardiac-related complications (HR = 1.69; 95% CI, 1.31-2.18) and diabetes (HR = 1.88; 95% CI, 1.42-2.48).
The 3-year OS rates were 46% (95% CI, 44-48) for GnRHa and 39% (95% CI, 35-44) for orchiectomy (log-rank P = .03).
Both treatments resulted in similar median total expenditures at 12 months following diagnosis ($9,726.98 for orchiectomy vs. $8,478.46 for GnRHa).
The researchers acknowledged limitations of their study, including its retrospective design and older cohort. Further, they noted that due to a coding issue, PSA data were unavailable.
“In some patients who need permanent androgen suppression, surgical castration may represent a suitable alternative to GnRHa,” Trinh and colleagues wrote. “However, other considerations must be contemplated when deciding medical or surgical castration, such as young age and intermittent ADT."
In an accompanying editorial, Michael Kolinsky, BSc, MD, Pasquale Rescigno, MD, and Johann S. de Bono, MDChB, MSc, FRCP, PhD, FMedSci, all of The Institute for Cancer Research and The Royal Marsden National Health Service Trust in London, noted that patient preference and similar relevant factors should be considered when deciding treatment.
“Because men with metastatic prostate cancer are living longer than ever, it is imperative that we minimize the risk of harm from therapies,” they wrote. “Physicians treating patients with prostate cancer must familiarize themselves with how to prevent and treat these complications. … When there is more than one reasonable option, clinical decisions must be guided by the patient’s values and preferences. In the absence of clear evidence to the contrary, patients are likely to continue to overwhelmingly favor GnRHa over orchiectomy.” – by Cameron Kelsall
Disclosure: Trinh reports no relevant financial disclosures. Other study researchers report honoraria from and advisory board roles with Bayer, as well as consultant roles with Genome Dx and Medivation. Kolinsky, Rescigno and de Bono report no relevant financial disclosures.
Click Here to Manage Email Alerts