an increasing trendp=0.001
squamous cell carcinoma oral cavity cancer pharyngeal cancer human papilloma virus (HPV) epidemiology incidence mortality Russian Federation For OPCs (C10-C13), an increasing trend for both sexes was observed over time at a rate of 0.031 cases per 100,000 individuals per year (R 2 = 0.68, p=0.001, Figure 2 ).