JOURNAL OF THE LOUISIANA STATE MEDICAL SOCIETY
benefit. These reasons were then followed by “fear that it would condone sexual activity” and the “desire to avoid vaccines altogether” as the third and fourth, respectively. Only 32.7% of respondents were very familiar with the link between HPV and oropharyngeal cancer. The majority (51.8%) of respondents indicated that they have only some awareness of this link and 15.4% were not aware of HPV positive oropharyngeal cancer. Among the respondents, 45.9% believed rates of HPV associated with oropharyngeal carcinoma are rising, and 44% reported not having knowledge about the increasing rate. A number of respondents (17.2%) did indicate that more knowledge of HPV-associated oropharyngeal cancers would increase their recommendation of the vaccine for males. Practice setting and length of practice did not correlate with knowledge of the link between HPV and oropharyngeal cancer (Table 2, Table 3, p = 0.35 and p = 0.88, respectively).
prevention of HPV associated malignancies, rates of vaccination in the U.S. remain unacceptably low. 7 The 2014 National Immunization Survey- Teen (NIS-Teen) showed that 60.0% of females and 41.7% of males ages 13-17 years received one or more doses of HPV vaccine. 25 These rates are well below those for Tdap and meningococcal vaccines, both of which are recommended for the same age group. 26 The disparity between male and female vaccination rates are particularly concerning given males have a 4.7 fold higher risk of developing HPV(+) OPC. 27 While federal mandates in other countries have achieved high rates of vaccination, only three states in the U.S. have passed legislation for school mandated vaccination. As the subject of mandatory vaccination for a sexually transmitted virus has been controversial in this country, more widespread use of mandates is unlikely at this time. 28 Therefore, education of providers and parents is likely to be the most productive effort to improve current vaccination rates. This study examined practice patterns amongst pediatricians in Louisiana. Although the majority of pediatricians routinely recommend vaccination, we found that for some, the strength of the recommendation depends on the age or sex of the patient. This study also demonstrates that even amongst medical professionals who consistently offer HPV vaccine there is limited knowledge of its role in the prevention of HPV (+) OPC. Despite the high rate of recommendation, less than one third of participants were highly familiar with the link between HPV and OPC and only half were aware of any association. In addition, the majority of participants were unaware of the rising rate of HPV (+) OPC. There was no correlation between practice setting or length of practice in regards to knowledge of HPV (+) OPC. These results further imply that there is a greater need for improved awareness among all medical professionals irrespective of practice setting and experience. Additionally, although offering vaccination against HPV is an important step in increasing vaccination rates in the U.S., many parents may not feel compelled to vaccinate their children if they are not made aware of its major benefit: the prevention of HPV-related cancers. In a survey of 102 participants consisting of health care providers, community leaders, parents with adolescent sons, and young adult men ages 18-26, few had even heard of the availability of the vaccine for men and its role in throat cancer. 29 Health care professionals (HCP) play an integral role in education of the public. In a recent systematic review concerning barriers to HPV vaccination in US adolescents, parents consistently mentioned HCP’s recommendations as one of the most influential considerations in their choice to vaccinate their children. 30 In a study examining young women ages 19-26, patients were found have a 4-fold greater rate of vaccination if their physician gave a strong recommendation versus one that was not strong. 31 Another study based on a 2009 U.S. national panel of 18- 59-year-old men reported factors associated with HPV vaccine acceptability and demonstrated that more respondents were willing to be vaccinated when the vaccine was presented as preventing genital warts and anal, oral, or penile cancer than when framed as preventing genital warts alone. 32 Additionally, parents in another investigation identified
DISCUSSION
The possible role of HPV in the development of OPC was first suggested in 1983 and then became established in the late 80s and 90s. 11-15 However, it took almost a decade to gather the epidemiological evidence for the association and to understand the biological mechanisms behind the viral-mediated tumorigenesis. 16-18 Similar to the HPV related cervical cancer, OPC (approximately 90%) is driven primarily by HPV 16 with the rest attributed to HPV 18. 18 In a study of a representative sample of the U.S. population in 2009-2010, the prevalence of HPV type 16 was 1% in 14-69 year old men and women. 19 HPV(+) Head and Neck Squamous Cell Carcinoma (HNSCC) predominantly arises in the oropharynx, the middle portion of the throat that, compromises the soft palate, palatine tonsils, base of tongue, and lateral and posterior pharyngeal walls. Traditional risk factors for HNSCC include tobacco and alcohol abuse. However, HPV (+) HNSCC possesses a unique molecular pathology compared to the other HNSCCs, 20,21 and therefore represents a distinct clinical entity. HPV (+) patients tend to be younger compared to HPV (-) patients, male, Caucasian, college educated, have an annual income greater than $50,000 and are more often non-smokers or drinkers. 22 No direct studies of the effect of HPV vaccine on persistent infection with HPV 16 have been reported. However, in a single evaluation of the prevalence of oral infection in a vaccinated population, decreased carriage of HPV 16 was demonstrated after immunization with bivalent HPV 16/18 vaccine. During the fourth year evaluation of subjects in a double blind randomized trial of bivalent HPV 16/18 vaccine in 7,466 women in Costa Rica, an oral wash was obtained from 5,840 women (91.9% of the eligible population). Fifteen control subjects and one vaccinated subject were positive for HPV 16/18, giving a vaccine effectiveness of 93.3%. 23-24 These findings support the concept that HPV vaccineswill affordprotection against the development of HPV (+) OPC.
Despite the observed safety, early demonstrated effectiveness, and predicted long-term benefits of HPV vaccination in the
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