High-risk human papillomavirus detection in oropharyngeal cancers: Comparison of saliva sampling methods

Background Accumulating evidence has suggested the utility of salivary oral rinse as a diagnostic fluid to detect oral human papillomavirus (HPV) DNA, but there are many methods for collecting saliva. Methods Salivary oral rinse and unstimulated whole mouth saliva samples were collected from 45 oropharyngeal cancer (OPC) patients. Results We show a positive correlation of HPV-16 E2 (r = 0.95, P < 0.0001) and E6/7 (r = 0.93, P < 0.0001) relative copy number as well as HPV genotypes in both sample methods. There was a significant correlation between the two sample methods in the ratio of HPV16 E2 to E6/7 DNA (r = 0.46, P < 0.01). Consistent with previous studies, a mixed HPV-16 form (episomal and integrated) was commonly found in both saliva and tumor samples. Conclusion Detection of HPV in saliva samples collected by either method yielded comparable results, and showed good sensitivity for detection of HPV derived from OPC.