title: Tamoxifen for the management of breast events induced by non-steroidal antiandrogens in patients with prostate cancer: a systematic review.
abstract: BACKGROUND
  Tamoxifen has emerged as a potential management option for gynecomastia and breast pain due to non-steroidal antiandrogens, and it is considered an alternative to surgery or radiotherapy. The objective of this systematic review was to assess the benefits and harms of tamoxifen, in comparison to other treatment options, for either the prophylaxis or treatment of breast events induced by non-steroidal antiandrogens in prostate cancer patients.
  
  
  METHODS
  We searched CENTRAL, MEDLINE, EMBASE, reference lists, the abstracts of three major conferences and three trial registers to identify ongoing randomized controlled trials (RCTs). Two authors independently screened the articles identified, assessed the trial quality and extracted data. The protocol was prospectively registered (CRD42011001320; http://www.crd.york.ac.uk/PROSPERO).
  
  
  RESULTS
  Four studies were identified. Tamoxifen significantly reduced the risk of suffering from gynecomastia (risk ratio 9RR0 0.10, 95% CI 0.05 to 0.22) or breast pain (RR 0.06, 95% CI 0.02 to 0.17) at six months compared to untreated controls. Tamoxifen also showed a significant benefit for the prevention of gynecomastia (RR 0.22, 95% CI 0.08 to 0.58) and breast pain (RR 0.25, 95% CI 0.10 to 0.64) when compared to anastrozole after a median of 12 months. One study showed a significant benefit of tamoxifen for the prevention of gynecomastia (RR 0.24, 95% CI 0.09 to 0.65) and breast pain (RR 0.20, 95% CI 0.06 to 0.65) when compared with radiotherapy at six months. Radiotherapy increased the risk of suffering from nipple erythema and skin irritation, but there were no significant differences for any other adverse events (all P>0.05).
  
  
  CONCLUSIONS
  The currently available evidence suggests good efficacy of tamoxifen for the prevention and treatment of breast events induced by non-steroidal antiandrogens. The impact of tamoxifen therapy on long-term adverse events, disease progression and survival remains unclear. Further large, well-designed RCTs, including long-term follow-ups, are warranted. Also, the optimal dose needs to be clarified.
authors.affiliation: German Cochrane Center, Institute of Medical Biometry and Medical Informatics, University Medical Center Freiburg, Berliner Allee 29, 79110 Freiburg/Br., Germany. frank.kunath@uk-erlangen.de
authors.forename: Frank
authors.initials: F
authors.lastname: Kunath
authors.forename: Bastian
authors.initials: B
authors.lastname: Keck
authors.forename: Gerd
authors.initials: G
authors.lastname: Antes
authors.forename: Bernd
authors.initials: B
authors.lastname: Wullich
authors.forename: Joerg J
authors.initials: JJ
authors.lastname: Meerpohl
mesh_terms: D000726:Androgen Antagonists / Q000009:adverse effects* / Q000627:therapeutic use; D006177:Gynecomastia / Q000139:chemically induced / Q000188:drug therapy* / Q000517:prevention & control*; D006801:Humans; D008297:Male; D059373:Mastodynia / Q000139:chemically induced / Q000188:drug therapy* / Q000517:prevention & control*; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D016032:Randomized Controlled Trials as Topic; D013629:Tamoxifen / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D013629:Tamoxifen