In the US, an increasing number of throat (oropharyngaeal) cancer cases are associated with human papillomavirus (HPV) infection. Throat cancer accounts for less than 3% of all cancers diagnosed each year in the US and the risk factors include tobacco use, alcohol consumption and HPV infection. According to the US Centres for Disease Control and Prevention (CDC), around three-quarters of newly diagnosed cases are linked to HPV infection. HPV-associated throat cancer does not have recognisable symptoms in the earlier stages, such as difficulty swallowing or pain, until the tumour is large and has spread to other organs. Because of this, the burden of throat cancer is expected to increase in the US, especially if it remains undiagnosed at the earlier stages.
GlobalData epidemiologists forecast that the diagnosed incident cases of throat cancer in the US will grow at an annual growth rate (AGR) of 1.1% per year over the next ten years, from 2,500 cases last year to 2,800 cases in 2030 (Figure 1). These cancer numbers represent cancers in specific areas of the oropharynx and do not include all areas of the oral cavity and larynx. In addition, GlobalData epidemiologists forecast that more than 70% of throat cancer cases are attributed to HPV, with HPV-associated throat cancer expected to reach 2,000 cases by 2030 (also shown in Figure 1). It is unclear if the virus alone is enough to cause this cancer or if it acts in combination with other risk factors such as tobacco and alcohol consumption.
HPV is one of the most common sexually transmitted infections. This infection is widely prevalent in the US, with more than 40 million cases diagnosed a year, and is especially common in the younger age population. The virus is mostly asymptomatic, but in some cases causes genital warts, cervical cancer and throat cancers. As HPV generally does not cause any symptoms, it is difficult to predict which one in the minority of cases will progress to other severe health conditions. HPV infection can be prevented with the approved vaccine, with the CDC recommending routine vaccination from the ages of 11–12 to 26 years. HPV vaccines were developed to prevent cervical cancer and are also assumed to prevent some types of oropharyngeal cancers, but this has not been proven conclusively.
Throat cancers are operable, with a five-year relative survival rate of more than 60%, provided the condition is diagnosed at an earlier stage. The cancer is difficult to diagnose, however, as it is mostly asymptomatic or has symptoms similar to a sore throat. As throat cancer is associated with HPV infection, smoking and alcohol consumption, the public health policy in early diagnosis and treatment tailored to these high-risk populations will help lessen the burden of this condition.