Human papillomavirus structural antigens in squamous papillomas of the male urethra

Twenty-five squamous papillomas of the male urethra were examined for the presence of human papillomavirus (HPV) whole (structural) virion antigens by a peroxidase-antiperoxidase technique having immunospecificity against genus-specific (common) antigens of the papillomavirus genus. Eleven of 25 (44 per cent) lesions were positive for HPV. The positive reaction was invariably intranuclear in the superficial epithelium. Evidence suggests that these papillomas arise by HPV infection of metaplastic squamous epithelium and not transitional epithelium. This study shows that at least some squamous papillomas of the male urethra are associated with HPV infections and suggest that this lesion may play an important role in venereally transmitted diseases such as cervical dysplasia and condylomas of the vulva and anus.