Human papillomavirus type 2 DNA in oral verrucous carcinoma

Tissues from patients with oral verrucous carcinoma were examined for the presence of human papillomavirus (HPV). The tissues were stained for the presence of the type common papillomavirus antigen by immunohistochemical staining and the presence of HPV DNA was determined by in situ hybridization with biotin-labelled HPV DNA probes. Seventeen tissue specimens were obtained from 9 patients, and included pre-malignant lesions and primary and recurrent tumors. One pre-malignant lesion was positive for papillomavirus structural antigen. This lesion and lesions from 2 other patients hybridized at low stringency (Tm-35 degrees) to 3 different HPV probes. By hybridization under high stringency conditions (Tm-20 degrees), the virus in each case was identified as being HPV2.