Prevalence of human papillomavirus in oropharyngeal squamous cell carcinoma in the United States across time

Abstract

Human papillomaviruses (HPVs) are involved in approximately 5% of all human cancer. Although initially recognized for causing nearly all cases of cervical carcinoma, much data has now emerged implicating HPVs as a causal factor in other anogenital cancers as well as a subset of head and neck squamous cell carcinomas (HNSCCs), most commonly oropharyngeal cancers. Numerous clinical trials have demonstrated that patients with HPV+ oropharyngeal squamous cell carcinoma (OPSCC) have improved survival compared to patients with HPV- cancers. Furthermore, epidemiological evidence shows the incidence of OPSCC has been steadily rising over time in the United States. It has been proposed that an increase in HPV-related OPSCCs is the driving force behind the increasing rate of OPSCC. Although some studies have revealed an increase in HPV+ head and neck malignancies over time in specific regions of the United States, there has not been a comprehensive study validating this trend across the entire country. Therefore, we undertook this meta-analysis to assess all literature through August 2013 that reported on the prevalence of HPV in OPSCC for patient populations within the United States. The results show an increase in the prevalence of HPV+ OPSCC from 20.9% in the pre-1990 time period to 51.4% in 1990-1999 and finally to 65.4% for 2000-present. In this manner, our study provides further evidence to support the hypothesis that HPV-associated OPSCCs are driving the increasing incidence of OPSCC over time in the United States.

Figure 1

Flow diagram depicting the exclusion and inclusion of articles used in our meta-analysis.

Figure 2

Prevalence of HPV in OPSCC over time in the United States. (A) Scatterplot demonstrating the prevalence of HPV in OPSCC reported by each article included in our analysis. The median year for the study’s sample collection period was used as the time point. (B) Boxplots of the HPV prevalence in OPSCC stratified into three time periods: pre-1990, 1990–1999, and 2000–present.

Figure 3

Frequency of HPV+ OPSCC detected by PCR versus ISH. The prevalence of HPV in OPSCC for articles with a median sample collection year from 1997 to the present employing ISH- or PCR-based methods for HPV detection. The relative size of the data point circle is dependent on the number of OPSCCs analyzed in the article.