Application of Human Papillomavirus-DNA Test on Salivary Gland Fine Needle Aspiration Cytology Samples Confirms the Absence of the Virus in Primary Neoplasms and Demonstrates for the First Time Its Presence in Salivary Intraglandular Cysts.

Abstract

The correlation between Human Papillomavirus (HPV) and salivary gland neoplasms is still controversial. Data in the literature are conflicting, reporting the presence of the HPV-DNA in a significant percentage of cases or none. We investigated the presence of HPV in a series of salivary gland neoplasms using fine needle aspiration cytology (FNAC) samples to explore its potential oncogenic role in salivary gland tumor development. The study included 66 salivary gland lesions from 65 patients. For all cases, residual cytological material in the needle hub, once direct smears were obtained, was fixed by rinsing the needle in Cytolyt hemolytic and preservative solution (Hologic Inc. Marlborough, MA 01752 USA). The samples fixed in the Cytolyt hemolytic and preservative solution (Hologic Inc. Marlborough, MA 01752 USA) were centrifuged at 252 g, then the sediment was transferred to the Preservcyt solution and used for the detection of HPV-DNA. We found evidence of the presence of HPV in two salivary intraglandular cysts lined by squamous cell epithelium. Furthermore, we also found HPV in three metastatic oropharyngeal squamous cell carcinomas (SCC) located in the parotid gland. Regarding primary salivary gland tumors, the HPV test produced negative results in all cases. HPV testing produced negative results in all primary salivary gland tumors, failing to confirm the potential involvement of HPV infection in the pathogenesis of salivary gland tumors. Instead, the presence of HPV DNA in samples of salivary intraglandular cysts, never reported before, may be an interesting fact, which however requires further evaluation.