Epstein–Barr virus-associated adenocarcinomas and squamous-cell lung carcinomas

The association of Epstein-Barr virus with pulmonary neoplasms has been restricted to lymphoepithelioma-like carcinomas in Asian patients. We have selected 19 pulmonary adenocarcinomas and squamous-cell carcinomas from 1545 pulmonary neoplasms diagnosed from 1996 to 2007 in an occidental population. All of them showed a low-power appearance confusing between an epithelial and a lymphoid neoplasm, with a dense lymphocytic infiltrate intermingled with neoplastic cells giving an image akin to lymphoepithelial complexes. Five carcinomas presented typical features of Lymphoepithelioma-like lung carcinomas; but six cases could be classified as squamous-cell carcinomas and eight as adenocarcinomas. A semiquantitative polymerase chain reaction method, Early RNA genes 1 and 2 in situ hybridization as well as Latent membrane protein immunostaining for Epstein-Barr virus DNA, RNA and protein detection methods were used in every case. None of Lymphoepithelioma-like carcinomas showed positivity for Epstein-Barr virus in any used method. Otherwise four squamous-cell carcinomas and eight adenocarcinomas (12 cases) demonstrated viral sequences in polymerase chain reaction and/or in situ hybridization analysis in neoplastic cells. Moreover two adenocarcinomas also displayed human herpesvirus 6 DNA sequences coamplification in molecular analysis. Protein immunostaining was focally positive in only three cases. We performed the same analysis in 70 more cases of conventional pulmonary squamous-cell carcinomas and adenocarcinomas that gave negative results. In conclusion, a subset of pulmonary squamous-cell carcinomas and adenocarcinomas show Epstein-Barr DNA and/or RNA sequences in neoplastic cells. This finding expands the spectra of epithelial cell common tumours Epstein-Barr virus associated.