Meta-analysis of the impact of human papillomavirus on cancer risk and overall survival in head and neck squamous cell carcinoma

Abstract

6080 Background: Human papillomavirus (HPV) is an important etiologic factor in HNSCC and its prevalence has been reported in several independent studies. We conducted a meta-analysis to determine the prevalence of HPV, its impact on risk of developing HNSCC and overall survival (OS). Methods: Pubmed search terms “HPV” and “HNSCC” were used to identify 40 clinical and translational studies between the years 1980–2008 that reported the prevalence of HPV in HNSCC. Statistical software STATA 10.0 was used in the meta-analyses to identify the association of HPV and HNSCC risk and OS. Pooled adjusted odds ratio (OR) or hazard ratio (HR) were obtained using a random-effects model. The amount of heterogeneity between studies was estimated with both the Chi-squared based Q test and the I2 statistic model. Potential sources of publication bias were detected using funnel plots. OS between the trials was compared in forest plot. Results: A total of 6,794 patients (pts) were included. The prevalence of HPV among HNSCC pts was 24.2%; and 86.8% of all HPV(+) tumors were HPV16. Thirteen studies (n = 1933 pts) determined HPV status by serology and the remainder detected HPV DNA in tumor tissue by PCR. Overall, HPV positivity conferred an increased risk for HNSCC (OR = 1.43; 95% CI 1.04–1.82). Risk for HNSCC among HPV16(+) pts was 4.47 times that of HPV16(-) pts. The OS was improved in HPV(+) pts compared to HPV(-) pts (HR = 0.40; 0.27–0.53). In HPV16(+) pts the HR for OS was 0.41 and the survival benefit was even more pronounced in the subgroup of HPV16(+) oropharyngeal cancers (HR = 0.38;0.17–0.58). Conclusions: This meta-analysis provides further evidence supporting the role of HPV as an important causative agent in HNSCC and supports HPV(+) HNSCC as a separate biologic entity which likely should be treated differently than HPV(-) HNSCC. Additional analysis on treatment outcomes to systemic and local therapy is ongoing. No significant financial relationships to disclose.