title: Duration of testosterone suppression after a 9.45 mg implant of the GnRH-analogue buserelin in patients with localised carcinoma of the prostate a 12-month follow-up study.
abstract: OBJECTIVE
  (1) To determine the duration of androgen deprivation after a single buserelin implant 9.45 mg in the neoadjuvant setting in combination with curative radiation therapy of carcinoma of the prostate, and (2) to evaluate the time to recovery of gonadal function, and the incidence and duration of hypogonadal symptoms.
  
  
  METHODS
  We prospectively evaluated 21 men with carcinoma of the prostate who received one implant of 9.45 mg buserelin subcutaneously. Release of buserelin, changes in serum testosterone concentration, hot flushing and sexual function over a 12-month study period were recorded.
  
  
  RESULTS
  Testosterone was suppressed below the castration limit (0.58 ng/ml=2 nmol/l) for 224 days (range, 139-309). The mean time to first return of testosterone above the castration limit was 246 days (range, 168-344); 50% of pre-treatment value was reached after 285 days (range, 218-370). The prevalence of hot flushing was 19 of 21 patients (90%) at 12 weeks. At the end of the study period, serum testosterone had reached 80% (range, 33%-166%) of pre-treatment concentration, sexual interest was present in 52%, erection was possible in 60%, and hot flushing remained in 24%.
  
  
  CONCLUSIONS
  A single injection of 3-month buserelin implant 9.45 mg suppresses serum testosterone below the castration limit for at least 6 months. Testosterone secretion recovers by 8-12 months. Hypogonadal symptoms decreased with the restoration of serum testosterone secretion. These data are clinically relevant regarding the dose schedule for buserelin and the patient information provided.
authors.affiliation: Department of Urology, Faculty of Health Sciences University Hospital, Linköping, Sweden.
authors.forename: Bill
authors.initials: B
authors.lastname: Pettersson
authors.forename: Eberhard
authors.initials: E
authors.lastname: Varenhorst
authors.forename: Anssi
authors.initials: A
authors.lastname: Petas
authors.forename: Jürgen
authors.initials: J
authors.lastname: Sandow
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use; D002064:Buserelin / Q000008:administration & dosage* / Q000627:therapeutic use; D002277:Carcinoma / Q000188:drug therapy* / Q000532:radiotherapy; D003131:Combined Modality Therapy; D004333:Drug Administration Routes; D004343:Drug Implants / Q000627:therapeutic use; D007172:Erectile Dysfunction / Q000139:chemically induced / Q000209:etiology; D005500:Follow-Up Studies; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives*; D019584:Hot Flashes / Q000139:chemically induced; D006801:Humans; D007989:Libido / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods; D011467:Prostate / Q000187:drug effects; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy; D012725:Sexual Behavior / Q000187:drug effects; D013739:Testosterone / Q000037:antagonists & inhibitors / Q000097:blood*; D013997:Time Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D004343:Drug Implants; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D002064:Buserelin