Immunoperoxidase localization of human papillomavirus in laryngeal papillomas

Five antigenically distinct serotypes of human papillomavirus (HPV) cause various cutaneous verrucae with distinct clinical features. Laryngeal and other mucosal papillomas, also suspected to have a viral etiology, were examined for the presence of a genus-specific (common) antigen of HPV using a peroxidase-antiperoxidase (PAP) technique. The primary antiserum used was reactive against laryngeal papillomas from 26 of 35 randomly selected patients (74%); overall, 49 of the 102 squamous papillomas stained were positive for HPV (48%). HPV antigen was not demonstrated within frankly dysplastic squamous cells. Nuclear localization of virus was confirmed by electron microscopy in 3 cases positive for HPV. PAP localization of HPV is rapid and more efficient than routine electron microscopy. Our data indicate a common pathogenesis for some papillomas and cutaneous verrucae and suggest a future role for immunohistochemistry in evaluating the epidemiology and pathobiology of laryngeal papillomatosis.