Reduction of capsular thickness around silicone breast implants by zafirlukast in rats

Capsular contracture is a very disappointing complication, with an overall incidence between 0.5 and 30% of breast implant operations and, if severe, requiring a further surgical procedure (capsulotomy or capsulectomy). Many frustrating attempts have been made to prevent the fibrotic reaction, mainly with steroids or antibiotics. More recently leukotriene antagonists clinically used in the asthma and lung diseases have been suggested to be potentially useful in counteracting the inflammatory pathway leading to a dense collagen membrane around the prosthesis and thus preventing contracture of the capsule. In this study we evaluated the effectiveness of zafirlukast with the following protocol. Disks of textured implant material were placed dorsally into each of the subcutaneous tissues of 40 rats that were subdivided in 2 groups: 20 rats treated with zafirlukast and 20 controls. At autopsy 77 days after, each implant with its surrounding collagenic tissue was excised, and the macroscopic measure of the membrane thickness was compared with the pathology reports, to definitely assess the foreign body reaction. The mean total thickness of the capsule around the implants was 161.97 microm in the zafirlukast-treated group compared with 345.98 microm in the control group (p < 0.001). Outstandingly, the collagen fibers and fibroblast layer were reduced in the zafirlukast-treated group compared to the controls. Our study confirms the effectiveness of this compound in preventing fibrosis and putatively also in reducing the extent of collagen reaction when a capsule has been formed.