In 2015, squamous cell<unk>  of the head and neck region was the fifth most common<unk>  other than skin<unk> , globally, with an annual incidence of 600,000 cases and about 60,000 cases annually in the United States and Europe. The global incidence of pharyngeal<unk>  in 2013 was estimated at 136,000 cases. For 2008 the Global Burden of Disease for OPC in 2008 is estimated at 85,000 cases, of which 22,000 were attributable to<unk> , a population attributable fraction (PAF) of 26%. Of these, 17,000 were males and 4,400 females, 13,000 (60%) were aged between 50 and 69 years of age, and the majority of cases (15,000) were in developed regions compared to developing regions (6,400). Age Standardised Incidence Rates (ASR) differ considerably by region and country (see de Martel et al., 2017 Fig. 2b). ASRs for 2012 were highest in Europe (Hungary 3.0) and North America (United States 1.7) but much lower in Africa (≤ 0.3), Asia (≤ 0.6), Latin America (≤ 0.4) and Oceania (≤ 0.2) (other than Australasia, Australia 0.9). Estimated average numbers of cases and ASR for the US in the period 2008–2012 were 15,738 and 4.5 respectively.<unk> +OPC was much more common in males than females (12,638, 7.6 and 3,100, 1.7). The highest incidence age group was 60–69, and was higher in Caucasians than in other races.<unk> +OPC patients tend to be younger than<unk> - patients in general. The clinical presentation is also changing from the “typical” head and neck<unk>  patient with advanced age and major substance usage. By contrast patients with<unk> +<unk>  are younger (4th–6th decades), male (ratio 8:1) with no or only a minimum history of smoking, generally Caucasian, reached higher education levels, are married, and have higher income. The risk factors for<unk> -OPC and<unk> +OPC tend to be independent, with the exception of smoking which has an adverse effect on both. The presenting features are also different between<unk> + and<unk> - OPC.<unk> + tumours have smaller primary lesions (less than 4 cm) but more advanced nodal disease resulting in higher TNM staging. This in turn may overestimate the severity of the disease status. Trends There has been a global trend in increasing OPC incidence, particularly in North America and northern Europe, but even in Taiwan, which has a very high rate for all<unk> s of the head and neck region, OPC rates increased more rapidly between 1995 and 2009 than any other<unk>  site. The Global Burden of<unk> +OPC increased from 22,000 in 2008 to 29,000 by 2012, and the PAF from 26% to 31%, and is considered an epidemic. In the United States the estimated number of cases was 12,410 in 2008, 13,930 in 2013 and 17,000 for 2017. Of these cases,<unk> +<unk>  has been increasing compared to<unk> -<unk> , but the increase in<unk> +OPC exceeds the decline in<unk> -OPC resulting an overall increase in OPC. The rise in pharyngeal<unk>  incidence contrasts with a marginal decline in other head and neck<unk> s. As a result, the commonest head and neck<unk>  has shifted from larynx to oropharynx. A survey of 23 countries between 1983 and 2002 showed an increase in<unk>  squamous cell carcinoma that was particularly noticeable in young men in economically developed countries. In the United Kingdom the incidence of oral and<unk><unk>  in men rose 51%, from 7/100,000 to 11/100,000 between 1989 and 2006. In the US there is a growing incidence of<unk>  associated<unk><unk> s, In the early 1980s<unk> + accounted for only 7.5% of cases in the US but by 2016 this was 70%, perhaps as a result of changing sexual behaviors, decreased popularity of tonsillectomies, improved radiologic and pathologic evaluation, and changes in classification. Tonsil and<unk><unk> s increased in male predominance between 1975 and 2004, despite reductions in smoking.<unk> -OPC decreased with decreasing smoking rates from 1988 to 2004, while<unk> +OPC increased by almost 7.5% per year from about 16% of all cases of OPC in the early 1980s to almost 70% in 2004. The decline in smoking may be linked to the decreasing proportion of<unk>  negative<unk> s, while changes in sexual activity may be reflected in increasing proportion of<unk><unk><unk> s. Recently, in the US,<unk>  associated OPC represent about 60% of OPC cases compared with 40% in the previous decade. By 2007, in the US, incidence of general OPC, including non-HPV associated, is 3.2 cases per 100,000 males/year and 1.9 per 100,000 all-sexes/year. This makes<unk> +OPC one of only five<unk> s that have increased in incidence in the US since 1975. The largest increase in incidence has occurred in patients under age 50. The increase in incidence of<unk>  associated OPC is also seen in other countries, like Sweden, with a 2007 incidence of over 80% for<unk>  in the tonsils, Finland and the Czech Republic. Partners of patients with<unk>  do not seem to have elevated oral<unk>  infection compared with the general population. In Australia the incidence of<unk>  associated OPC was 1.56 cases per 100,000 males/year (2001–2005), rising from 19% (1987–90), to 47% (2001–05) and 63.5% (2006–2010). In Canada the percentage of cases of OPC attributable to<unk>  increased from 47% in 2000 to 74% in 2012.
HPV-positive oropharyngeal cancer
Tobacco
Hepatitis C and HIV coinfection
Branchial cleft cyst
Circumcision and HIV
Oral florid papillomatosis
Hormone receptor positive breast tumor
Human papillomavirus infection