Introduction: Luteinizing hormone-releasing hormone (LHRH) agonists are an androgen deprivation therapy used in advanced prostate cancer. The LHRH agonist histrelin is available as an implant of histrelin acetate for once-yearly subcutaneous administration into the upper arm. A single-center, clinical retrospective chart review was performed to characterize the safety and efficacy of abdominal insertion of the histrelin acetate implant.
Methods: Data were collected retrospectively from the charts of 64 patients aged > 45 years with prostate cancer who received the histrelin acetate implant subcutaneously inserted into the abdomen at a single center. Of these, 37 patients received a second implant after 1 year.
Results: Following the first implant, mean serum testosterone levels were 0.38 nmol/L (10.89 ng/dL) at 6 months (n = 19) and 0.52 nmol/L (14.96 ng/dL) at 12 months (n = 33); serum testosterone level was < 1.04 nmol/L (< 30 ng/dL) in 94.7 and 90.9% of patients at 6 and 12 months, respectively. Mean serum prostate-specific antigen levels were 6.56 μg/L (6.56 ng/mL) at 6 months (n = 23) and 4.58 μg/L (4.58 ng/mL) at 12 months (n = 40). Efficacy was maintained in patients who received a second implant. Adverse events occurred in 3 patients. Eleven patients died during the chart review period; these deaths were deemed unrelated to histrelin acetate implant use. Conclusion: Insertion of the histrelin acetate implant into the abdomen appears to be an effective and generally well-tolerated alternative administration method. Paul F Siami, Knox Beasley, Sean Woolen, Joseph Zahn
KEYWORDS: histrelin acetate, implant, prostate cancer, subcutaneous
CORRESPONDENCE: Paul F Siami, MD, Department of Urology, Deaconess Clinic, 421 Chestnut Street, Evansville, Indiana, 47713, United States ( ).
CITATION: UroToday Int J. 2012 June;5(3):art 26.
doi: http://dx.doi.org/10.3834/uij.1944-5784.2012.06.13
