Breast Implants Elicit Local and Systemic Immune Response: Evidence for Breast Cancer Immunosurveillance.

[BACKGROUND] Women with cosmetic implants have lower rates of future breast cancer than the general population. The authors hypothesized that the implant foreign body response could induce a local protective anticancer immunosurveillance. The authors expanded on their previous finding, which showed that women with breast implants have elevated antibody responses to certain breast cancer proteins.

[METHODS] Blood samples and breast tissue were collected from women undergoing first time breast augmentation (implant-naive [IN]) and revision breast augmentation (implant-exposed [IE]). Sera were collected and antibody levels to common breast cancer proteins were quantified by enzyme-linked immunosorbent assay. Reverse transcriptase-polymerase chain reaction was performed on breast tissue samples to quantify immune-related gene expression levels between IN and IE patients. Bulk RNA sequencing was performed to identify differentially expressed genes and altered signaling pathways in the breasts of IN patients versus IE patients.

[RESULTS] In total, 188 patients were recruited (IN, n = 117; IE, n = 71). Data demonstrated that IE patients had higher levels of antibodies to mucin-1, estrogen receptor-α, and mammaglobin A compared with IN patients. Mucin-1 expression was found to be higher in IE compared with IN breast tissue. RNA- sequencing analysis demonstrated up-regulated pathways in IE breast tissue for B-cell activation and development, T-helper cell type 2-related genes, T-cell activation, chemotactic factors, and responses to estrogen.

[CONCLUSIONS] This is the first study to demonstrate that periimplant inflammation extends beyond the implant capsule to the breast parenchyma. Women with breast implants have more activated B cells in the breast parenchyma and elevated antibody responses to breast cancer antigen.

[CLINICAL QUESTION/LEVEL OF EVIDENCE] Therapeutic, V.