Detection of human papillomavirus (HPV) DNA in focal epithelial hyperplasia.

Five focal epithelial hyperplasia (FEH) specimens from four patients were examined by Southern blot hybridization analysis to determine the specific human papillomavirus (HPV) types present. The histomorphologic features of these specimens were also evaluated and a broad variety of changes including koilocytes, mitosoid cells, ballooning cells and cells showing individual cell keratinization were noted. FEH lesions from the three patients sharing a familial relationship demonstrated HPV DNA sequences that were either the prototype HPV-13 or a very closely related HPV-13 subtype. These patients also showed similar clinical features. Lesional tissue from the other patient was found to harbor HPV DNA sequences similar to HPV-32. In view of these findings it is suggested that these specific HPV types are associated with the characteristic FEH histomorphology described.