INVERTED PAPILLOMAS OF THE PARANASAL SINUSES AND THE NASAL CAVITY - DNA INDEXES AND HPV INFECTION

Inverted papillomas are rare tumors of the nasal cavity and paranasal sinuses. These tumors are commonly regarded as benign lesions; neverth eless, malignant transformation occurs in up to 13% of cases. In the p resent retrospective study, specimens from 21 patients with inverted p apillomas of the paranasal sinuses and the nasal cavity were investiga ted in order to analyze the distribution of genetic imbalance and to c lassify chromosomal aneuploidy in these tumors as a predictor for thei r biological behavior. Currently, human papilloma viruses (HPVs) are a ccepted as tumor-inducing and -promoting agents involved in benign and malignant tumors of mucosal tissues in the upper aerodigestive tract. To date more than 80 HPV types have been identified by differences in the nucleotide sequences. Several types (e.g., HPV16, HPV18) are asso ciated with an increased risk for developing cancer. Other types (e.g. , HPV6/11) are identified more frequently in benign lesions of stratif ied mucous membranes. We detected HPV genomes by universal and specifi c primer polymerase chain reaction. Using degenerated primers derived from the L1 major envelope gene, an amplification of HPV DNA fragments of the correct size was observed in 7 of 21 cases. In one specimen, w here an inverted papilloma associated with a squamous cell carcinoma w as histologically confirmed, HPV18-specific primers detected the HPV18 genome. The tumors in which an amplification of HPV DNA fragments wer e observed showed the highest proliferation scores along with the high est rate of aneuploid cells detected by quantitative DNA analysis.