title: Safety of I.V. Nonnitrogen bisphosphonates on the occurrence of osteonecrosis of the jaw: long-term follow-up on prostate cancer patients.
abstract: BACKGROUND
  The aim of the study was to disclose information about the recently incorporated bisphosphonates therapies used to treat prostate cancer patients and their potential risks because the chemical nature and nitrogen content varies among the available drugs on the market.
  
  
  METHODS
  Three hundred twenty-four consecutive prostate cancer patients were submitted to bisphosphonates therapy after antiandrogen treatment was started. Zoledronic acid was administered monthly (n = 45), bimonthly (n = 15), trimonthly (n = 19), and semestrally (n = 15), and monthly intravenous clodronate was administered in an additional 156 cases. Fourteen additional cases switched the drugs during the course of the treatment.
  
  
  RESULTS
  After a median follow-up of 54 ± 24 (control), 63 ± 7 (clodronate), and 54 ± 6 months (zoledronic acid), the only 2 patients (0.6%) who developed osteonecrosis of the jaw (ONJ) occurred in those who switched the drug.
  
  
  CONCLUSIONS
  This study is the longest and the largest ever reported on bisphosphonates usage in prostate cancer patients. ONJ seems to be exclusively related to nitrogen content bisphosphonates.
authors.affiliation: Urology Clinic, Hospital Beneficência Portguesa of São Paulo, São Paulo, Brazil; Urology Department, Hospital Santa Helena of São Paulo, São Paulo, Brazil. Electronic address: paulortrodrigues@uol.com.br.
authors.forename: Paulo
authors.initials: P
authors.lastname: Rodrigues
authors.affiliation: Urology Clinic, Hospital Beneficência Portguesa of São Paulo, São Paulo, Brazil; Urology Department, Hospital Santa Helena of São Paulo, São Paulo, Brazil.
authors.forename: Flávio
authors.initials: F
authors.lastname: Hering
authors.affiliation: Urology Clinic, Hospital Beneficência Portguesa of São Paulo, São Paulo, Brazil; Urology Department, Hospital Santa Helena of São Paulo, São Paulo, Brazil.
authors.forename: Marcio
authors.initials: M
authors.lastname: Imperio
mesh_terms: D061605:Administration, Intravenous; D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000453:epidemiology*; D004002:Clodronic Acid / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004164:Diphosphonates / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004334:Drug Administration Schedule; D005500:Follow-Up Studies; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D016896:Treatment Outcome; D000077211:Zoledronic Acid
chemical_list: D000726:Androgen Antagonists; D004164:Diphosphonates; D007093:Imidazoles; D004002:Clodronic Acid; D000077211:Zoledronic Acid
keywords: Anti-androgen therapy; Clodronate; Osteonecrosis of the jaw; Prostate cancer; Zoledronic Acid