The screening of viral risk factors in tongue and pharyngolaryngeal squamous carcinoma.

BACKGROUND The oral cavity and pharyngolarynx is readily open to the environment, which provides a good atmosphere to viral infection and subsequently links to the local carcinogenesis. The aim of this study is to clarify the viral risk factors for tongue and pharyngolaryngeal squamous carcinomas and the oncogenic role of DNA viruses. MATERIALS AND METHODS Tongue, pharyngeal and laryngeal carcinomas, and corresponding non-neoplastic mucosa (NNM) were collected and subjected to microdissection and DNA extraction with integrity detected by beta-globin polymerase chain reaction(PCR). Additionally, we examined genomic DNA copies of Epstein-Barr virus (EBV), human papilloma virus (HPV) 16 and 18, and John Cunningham virus (JCV) by real-time PCR with a comparison of the clinicopathological features of the tumors. RESULTS All the extracted DNA samples showed good integrity. Compared with NNM, EBV and HPV16 copies were higher in the three kinds of head and neck carcinoma respectively (p<0.05). The same situation was also observed in tongue and pharyngeal carcinoma for HPV18, and pharyngeal carcinoma for JCV (p<0.05). There were fewer EBV copies in tongue than pharyngeal and laryngeal carcinoma (p<0.05). Pharyngeal carcinoma had a higher HPV16 copy number than tongue and laryngeal carcinoma (p<0.05). Moderately differentiated carcinoma of the head and neck had more EBV copies than well-differentiated (p<0.05). CONCLUSION The viruses studied here might play an important role in the carcinogenesis of tongue and pharyngolaryngeal squamous carcinomas.