Oral Human Papillomavirus Infection Before and After Treatment for Human Papillomavirus 16-positive and Human Papillomavirus 16-negative Head and Neck Squamous Cell Carcinoma

Purpose: Oral human papillomavirus (HPV) infection is a risk factor for head and neck squamous cell carcinoma (HNSCC), and is a concern for patients with HPV-positive HNSCC and their partners. The prevalence of oral HPV infection before and after cancer therapy was investigated among patients with HPV16-positive and HPV16-negative HNSCC.

Experimental Design: Serial oral rinse samples (ORS) were collected from a cohort of 135 HNSCC cases as frequently as every 3 months for up to 3 years. Tumor HPV status was determined by HPV16 in situ hybridization. HPV was detected in ORS by consensus PCR and line blot hybridization. The HPV16 variants in positive oral rinse-tumor pairs were determined by sequencing. The odds of oral HPV infection among HPV16-positive and HPV16-negative cases were compared by use of generalized estimating equations.

Results: Patients were followed for a median of 21 months and provided a median of 4 samples. Forty-four of 135 patients had HPV16-positive tumors. HPV16-positive cases were more likely than HPV16-negative cases to have an oral HPV infection detected before (odds ratio, 8.6; 95% confidence interval, 3.5-21) and after therapy (OR, 2.9; 95% confidence interval, 1.1-7.4). Oral infections by HPV16 and other high-risk, but not low-risk, types were more common among HPV16-positive cases both before and after therapy. Most HPV16 variants in ORS were European, unique, and identical to that in the tumor. Persistence of a type-specific oral infection was demonstrable for as long as 5 years.

Conclusion: Oral high-risk HPV infections are more frequent among patients with HPV16-positive than HPV16-negative HNSCC, consistent with a behavioral and/or biological disposition to infection.