Bacterial Biofilm Infection Detected in Breast Implant–Associated Anaplastic Large-Cell Lymphoma

<jats:sec> <jats:title>Background:</jats:title> <jats:p>A recent association between breast implants and the development of anaplastic large-cell lymphoma (ALCL) has been observed. The purpose of this study was to identify whether bacterial biofilm is present in breast implant–associated ALCL and, if so, to compare the bacterial microbiome to nontumor capsule samples from breast implants with contracture.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods:</jats:title> <jats:p>Twenty-six breast implant–associated ALCL samples were analyzed for the presence of biofilm by real-time quantitative polymerase chain reaction, next-generation sequencing, fluorescent in situ hybridization, and scanning electron microscopy, and compared to 62 nontumor capsule specimens.</jats:p> </jats:sec> <jats:sec> <jats:title>Results:</jats:title> <jats:p>Both the breast implant–associated ALCL and nontumor capsule samples yielded high mean numbers of bacteria (breast implant–associated ALCL, 4.7 × 10<jats:sup>6</jats:sup> cells/mg of tissue; capsule, 4.9 × 10<jats:sup>6</jats:sup> cells/mg of tissue). Analysis of the microbiome in breast implant–associated ALCL specimens showed significant differences with species identified in nontumor capsule specimens. There was a significantly greater proportion of <jats:italic toggle="yes">Ralstonia</jats:italic> spp. present in ALCL specimens compared with nontumor capsule specimens (<jats:italic toggle="yes">p</jats:italic> < 0.05). In contrast, significantly more <jats:italic toggle="yes">Staphylococcus</jats:italic> spp. were found associated with nontumor capsule specimens compared with breast implant–associated ALCL specimens (<jats:italic toggle="yes">p</jats:italic> < 0.001). Bacterial biofilm was visualized both on scanning electron microscopy and fluorescent in situ hybridization.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions:</jats:title> <jats:p>This novel finding of bacterial biofilm and a distinct microbiome in breast implant–associated ALCL samples points to a possible infectious contributing cause. Breast implants are widely used in both reconstructive and aesthetic surgery, and strategies to reduce their contamination should be more widely studied and practiced.</jats:p> </jats:sec> <jats:sec> <jats:title>CLINICAL QUESTION/LEVEL OF EVIDENCE:</jats:title> <jats:p>Risk, V.</jats:p> </jats:sec>