Epstein-Barr virus infection is not associated with fibroadenomas of the breast in immunosuppressed patients after organ transplantation.

Epstein-Barr virus has been linked to an increasing number of nonhematolymphoid conditions. Epstein-Barr virus was recently described in association with fibroadenomas of the breast occurring in immunosuppressed patients. To further investigate the potential association of Epstein-Barr virus with fibroadenoma in the context of immune dysfunction, 11 cases of fibroadenoma of the breast in immunosuppressed organ transplant recipients were examined. Cases were evaluated for the presence of Epstein-Barr virus by polymerase chain reaction, in situ hybridization, and immunohistochemical methods. The presence of Epstein-Barr virus genomic DNA was studied by polymerase chain reaction amplification using primers flanking the BamHI-W fragment of the Epstein-Barr virus genome, as well as the Epstein-Barr virus nuclear antigen-4 and latent membrane protein-1 genes. Cases were also evaluated for the presence of defective heterogeneous Epstein-Barr virus DNA. In addition, morphologic analysis by in situ hybridization for Epstein-Barr virus-encoded RNA-1 and immunohistochemistry for latent membrane protein-1 were performed. Epstein-Barr virus DNA was detected in 4 of 11 (36%) cases with BamHI-W polymerase chain reaction. Polymerase chain reaction studies for Epstein-Barr virus nuclear antigen-4 and latent membrane protein-1 genes were positive in two and four cases, respectively. No defective Epstein-Barr virus genomes were identified in any of the cases. Quantitative polymerase chain reaction demonstrated low levels of Epstein-Barr virus in the fibroadenomas studied. Despite the detection of Epstein-Barr virus genomes in a subset of the cases examined, the constituent epithelial and stromal components of all fibroadenomas demonstrated no evidence of Epstein-Barr virus-encoded RNA-1 by in situ hybridization or latent membrane protein-1 expression by immunohistochemistry. Rare Epstein-Barr virus-encoded RNA-1-positive lymphocytes were observed in some cases, which may account for the positive polymerase chain reaction results. The findings of the present study argue against a significant relationship between Epstein-Barr virus and fibroadenomas of the breast in the setting of transplant-associated immunosuppression.