Myth: Decreased smoking rates have had no impact on incidence of head and neck squamous cell carcinoma (HNSCC)
Fact: Between 1974 to 1999, there was a decrease in oral cavity, laryngeal, and hypopharyngeal cancers in the United States. This was largely attributed to a decreasing incidence in smoking. Notably, there was no significant difference in the incidence of nasopharyngeal cancers and there has been an increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC). The increase in OPSCC has been attributed to the human papilloma virus (HPV).
Myth: With the development of the HPV vaccination, the incidence of HPV-positive OPSCC is declining
Fact: The incidence of HPV-positive OPSCC is rising. There has been an astounding increase of 228% of OPSCC in the United States between 1988 and 2004. It is estimated that HPV-associated OPSCC comprises about 70% of cases of OPSCC. Furthermore, between 2002 and 2012, the rate of HPV-related oropharyngeal cancer increased by 2.5% per year (p value < .0001). The rising rate of HPV-positive HNSCC extends beyond the United States, with the literature showing that the incidence of HPV-positive cancers is also growing in Korea. In fact, HPV-associated OPSCC is estimated to surpass cervical cancer as the most common HPV-related cancer in the next year.
Myth: The incidence of HPV-positive cancers is similar between males and females
Fact: Men are 2.8 to 5 times more likely than women to have HPV-positive OPSCC. The discrepancy between men and women is thought to be in part related to sexual behavior variation. Men were found to have more lifetime oral and vaginal sexual partners, which has been associated with the development of OPSCC. The variation in incidence of HPV-positive OPSCC between men and women could also be attributed to the lagging HPV vaccination recommendations for men. The HPV vaccination was approved for girls in 2006, however it was not approved for boys until 2009.
Myth: Smokeless tobacco does not carry an increased risk of development of HNSCC
Fact: Smokeless tobacco does carry an increased risk of development of HNSCC. The incidence of HNSCC associated with smokeless tobacco varies based on regional prevalence of smokeless tobacco use. In India, more than 50% of oral cancers in men and women were attributed to the use of smokeless tobacco products. A multicenter case control study from India showed that there is an increase in hypopharyngeal cancers in never smokers but not laryngeal cancers. In Sudan and the US, 68% and 4% of oral cancers in men were attributed to smokeless tobacco use, respectively. Another study assessing betel quid use from Pakistan showed a similar increase in risk of oral cancer even after adjusting for tobacco smoking.
Myth: Alcohol does not have an independent impact on the risk of developing HNSCC
Fact: Alcohol does have an independent effect on the risk of developing HNSCC. Alcohol consumed at high frequency (greater than or equal to three drinks per day) is associated with a 2-fold increase in the likelihood of developing head and neck cancer compared to never drinkers. There is a multiplicative effect of alcohol and tobacco use on development of HNSCC. People who consume 84g/day of ethanol and 10 cigarettes per day are at a 35-fold increased risk of developing HNSCC compared to never drinkers and never smokers.