title: Histologic analysis of zafirlukast's effect on capsule formation around silicone implants.
abstract: BACKGROUND
  The most common complication experienced by patients who have undergone mammary implant surgery is capsular contracture. This matter concerns physicians and patients, but to date, there is no effective way to avoid this complication. Surgical intervention usually is required. In 2002, the use of zafirlukast, a leukotriene inhibitor (a drug used for asthma treatment), was reported for the treatment of capsular contracture, with good results.
  
  
  METHODS
  For this study, 30 female Wistar rats were used. These animals received two silicone implants each: one with a smooth surface and one with a textured surface. All the animals received daily intraperitoneal injections for 90 days and were divided as follows: control group (C) receiving only saline solution, experimental group 1 (E-I) receiving 1.25 mg/kg/day of zafirlukast, and experimental group 2 (E-II) receiving 5 mg/kg/day of zafirlukast. Histologic analysis used hematoxilin and eosin to verify vessels, capsule thickness, and inflammatory cells. Immunoistochemical analysis with smooth muscle anti-actin antibody was used for myofibroblast verification. Picro-Sirius under polarized light was used for collagen analysis.
  
  
  RESULTS
  Textured implant experimental groups presented smaller numbers of vessels, thinner capsules, lower collagen density, and smaller numbers of mastocytes and eosinophils than the control group. No significant differences were found in smooth surface implants, as compared with the control group.
  
  
  CONCLUSIONS
  Zafirlukast reduced the occurrence of factors directly and indirectly connected with capsular contracture.
authors.affiliation: Division of Plastic Surgery, Department of Surgery, Federal University of São Paulo, Escola Paulista de Medicina, Rua Napoleão de Barros, 715, 4o andar HSP, Vila Clementino, 04024-002, São Paulo, SP, Brazil. erika.mb@uol.com.br
authors.forename: Erika M
authors.initials: EM
authors.lastname: Bastos
authors.forename: Miguel S
authors.initials: MS
authors.lastname: Neto
authors.forename: Maria Teresa S
authors.initials: MT
authors.lastname: Alves
authors.forename: Elvio B
authors.initials: EB
authors.lastname: Garcia
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Santos
authors.forename: Thaís
authors.initials: T
authors.lastname: Heink
authors.forename: Juliana B
authors.initials: JB
authors.lastname: Pereira
authors.forename: Lydia M
authors.initials: LM
authors.lastname: Ferreira
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018427:Breast Implants / Q000009:adverse effects*; D005260:Female; D005549:Foreign-Body Reaction / Q000188:drug therapy* / Q000209:etiology; D007211:Indoles; D020024:Leukotriene Antagonists / Q000008:administration & dosage*; D048448:Phenylcarbamates; D051381:Rats; D017208:Rats, Wistar; D020034:Silicone Gels / Q000009:adverse effects*; D013449:Sulfonamides; D014105:Tosyl Compounds / Q000008:administration & dosage*
chemical_list: D007211:Indoles; D020024:Leukotriene Antagonists; D048448:Phenylcarbamates; D020034:Silicone Gels; D013449:Sulfonamides; D014105:Tosyl Compounds; C062735:zafirlukast