Prevalence, morphology, and prognosis of human papillomavirus in tonsillar cancer

We sought to identify the prevalence of human papillomavirus (HPV) in tonsillar squamous cell carcinoma, and to examine the relationship of HPV to prognosis and tumor morphology.

We performed in situ hybridization for HPV and retrospective clinical outcome analysis.

Of the 48 patients with tonsillar carcinoma, in situ hybridization identified 35% as HPV-positive tumors. Age-matched controls had no evidence of HPV. There was no significant difference between HPV-positive and HPV-negative patients regarding age (p = 0.34), tobacco consumption (p = 0.59), alcohol consumption (p = 0.91), or treatment method (p = 0.39). Forty-four patients were eligible for outcome analysis. The overall rate of recurrence in this population was 25%, and the disease-specific survival rate was 84%. There was no significant difference between the two groups either in the incidence of recurrence (p = 0.14) or in the disease-specific survival rate (p = 0.19). HPV-associated tumors developed from the tonsillar crypts significantly more frequently than did HPV-negative tumors (p = 0.01).

As previously described, HPV is significantly associated with squamous cell carcinoma of the tonsil; however, HPV status in our series did not correlate with clinical outcome. Morphologically, we found that HPV-positive tumors had their origin in the tonsillar crypts, whereas HPV-negative tumors arose from the surface epithelium.