Head and neck cancer (HNC) is responsible for substantial morbidity, mortality, and cost in the United States. Early detection and lifestyle risk factors associated with HNC, both determinants of disease burden and outcomes, are interrelated with public knowledge of this disease. Understanding of current public knowledge of HNC is lacking.
To assess awareness and knowledge of HNC among US adults.
Design, Setting, and Participants
Online survey of 2126 randomly selected adults in the United States conducted in 2013.
Online survey administration.
Main Outcomes and Measures
Subjective and objective assessment of knowledge of HNC including symptoms, risk factors, and association with the human papillomavirus.
Self-reported respondent knowledge of HNC was low, with 66.0% reporting that they were “not very” or “not at all” knowledgeable. This did not vary significantly with tobacco use (P = .92), education (P = .053), sex (P = .07), or race (P = .02). Regarding sites comprising HNC, 22.1% of respondents correctly identified throat cancer, 15.3% mouth cancer, and 2.0% cancer of the larynx, with 21.0% incorrectly identifying brain cancer as HNC. Regarding symptoms, 14.9% of respondents identified “red or white sores that do not heal,” 5.2% “sore throat,” 1.3% “swelling or lump in the throat,” and 0.5% “bleeding in the mouth or throat.” Smoking and chewing or spitting tobacco were identified by 54.5% and 32.7% of respondents as risk factors for mouth and throat cancer, respectively. Only 0.8% of respondents identified human papillomavirus (HPV) infection as a risk factor for mouth and throat cancer, but specific questioning revealed that 12.8% were aware of the association between HPV infection and throat cancer whereas 70.0% of respondents were aware of the vaccine targeting HPV.
Conclusions and Relevance
Self-reported and objective measures indicate that few American adults know much about HNC including risk factors such as tobacco use and HPV infection and common symptoms. Strategies to improve public awareness and knowledge of signs, symptoms, and risk factors may decrease the disease burden of HNC and are important topics for future research.
Head and neck cancer (HNC) is an important cause of mortality in the United States, with approximately 53 000 cases and 11 500 deaths predicted for 2013. Comprising the subsites of the oral cavity, pharynx, and larynx, HNC is the 10th most common cancer in the United States, accounting for approximately 3% of all adult malignant neoplasms.1 Head and neck cancer is 4 times more common in males and occurs more frequently among African Americans.1,2 It is primarily a disease of the adult and aging population, with 98% of cases occurring in patients older than 40 years and 50% in patients older than 60 years.3
Survival in HNC varies greatly both by primary tumor site and by stage of disease, with 5-year survival rates ranging from 89% for early-stage to 27% for advanced-stage disease.4 Early detection of HNC is associated with better outcomes.5,6 In the absence of proven imaging or blood chemistry testing, screening for HNC relies on thorough history and physical examination including visual and tactile examination of the nasal cavity, oral cavity, oropharynx, and neck, as well as indirect mirror or direct fiberoptic examination of the larynx and hypopharynx. Routine comprehensive head and neck evaluation is currently not recommended by the US Preventive Services Task Force7 and is uncommonly performed on asymptomatic patients, so diagnosis of HNC in its early stages depends on prompt recognition of signs and symptoms by the patient and subsequent self-referral.8
Head and neck cancer is a preventable disease, with estimates suggesting that more than 75% of cases in the United States are caused by tobacco use.9,10 Other risk factors include excessive alcohol intake, sun exposure (related primarily to lip cancer), and dietary factors including low consumption of fruits or vegetables.11 The incidence of HNC in the United States has been slowly decreasing over the last 3 decades, a trend thought to be related to decreasing smoking rates12; however, this trend was nonuniform among various demographic and social groups, prompting calls for early detection and prevention programs, particularly in groups of low socioeconomic status.12,13 In recent years, human papillomavirus (HPV) infection has been established as a risk factor for HNC associated with an increasing percentage of oropharyngeal tumors.14 Despite a decrease in the overall incidence of HNC, the incidence of oropharyngeal cancer has markedly increased over the last 2 decades, a trend attributed to HPV-mediated carcinogenesis.15
Little is known about public awareness and knowledge of signs, symptoms, and risk factors of HNC in the United States. Oral cancer is the most studied of HNCs, with several small data sets demonstrating poor public knowledge of symptoms and risk factors.16-20 There have been several campaigns to increase awareness of HNC, including the Head and Neck Cancer Alliance’s Oral Head and Neck Cancer Awareness Week21 and the Oral Cancer Foundation’s Oral Cancer Awareness Month,22 which together have involved screening of more than 10 000 Americans at more than 300 locations annually. Despite these efforts, which have been under way for more than a decade, limited available data suggest that awareness of HNC remains low.23 The American Academy of Otolaryngology–Head and Neck Surgery has also recently commented on a continuing need for increased HNC awareness through education and screening.24 Because HNC is largely preventable through avoidance of risk factors and treatment at early stages improves outcomes, increased public awareness could benefit both primary and secondary prevention of HNC.
Data and analyses of HNC awareness in the United States are lacking. This report addresses this gap in knowledge with results of a survey assessment of public knowledge of HNC conducted on behalf of the Head and Neck Cancer Alliance (HNCA). Findings presented here may serve as a benchmark for future studies and provide insight into the potential for educational and screening activities to decrease the burden of disease for HNC.
Survey Design and Administration
This work met the exemption criteria of the Yale University institutional review board. Written informed consent was obtained by Harris Interactive on recruitment of respondents. This survey was designed and funded by the HNCA (Charleston, South Carolina) and conducted by Harris Interactive (Rochester, New York). The survey was administered from January 2 through January 4, 2013. The Harris Interactive online survey methodology has previously been used in reports in various medical fields.25-28 Respondents were selected from the Harris Interactive online panel, which is recruited via a variety of methods, including World Wide Web, postal mail, television, and telephone advertising and invitations. This panel is designed and actively screened and updated by Harris Interactive along numerous demographic and psychographic variables to be representative of the adult US population and lessen nonrandom selection inherent to online surveys.29 Those panelists who participated in previous omnibus studies by the HNCA were excluded from the sample pool. Eligible panelists received an e-mail describing the study, and interested respondents were directed to a website where the survey could be completed.
Survey items included respondent demographic information, tobacco and alcohol use, and knowledge questions about HNC. Demographic information included sex, age, race, geographic location, and education. Race was measured as categories of white, black or African American, Asian or Pacific islander, Native American or Alaskan native, and other race with the option to decline to answer. Education was measured as less than high school, completed some high school, high school graduate or equivalent (eg, General Educational Development), completed some college but no degree, college graduate (eg, BA, AB, BS), completed some graduate school but no degree, completed graduate school (eg, MS, MD, PhD), and associate’s degree. Tobacco use was divided into current users, former smokers, and nonusers, and alcohol use was defined as consuming more than 4 alcoholic drinks per day. Knowledge questions included self-reported knowledge (“How knowledgeable are you about oral, head, and neck cancer?”) using a 5-point Likert scale including not at all, not very, somewhat, very, and extremely knowledgeable, as well as specific questions about definitions, symptoms, and risk factors of HNC. For questions with multiple, mutually nonexclusive answers, respondents were instructed to select “yes,” “no,” or “don’t know” for each answer choice.
Statistical analyses were performed using SPSS statistical software for Windows, version 20 (IBM). Descriptive analyses with calculated measures of central tendency and variation were computed, along with frequency tables for categorical variables. All demographic and substance use variables were treated as correlates, and all knowledge variables were treated as outcomes. Pearson χ2 and t tests were used to determine significance of association between categorical and continuous variables, with 1-way analysis of variance and post hoc Bonferroni adjustment used for multiple comparisons. Several variables were dichotomized, including race (to African American or black and non–African American or black), educational level (to college degree, including associate’s, and no college degree), tobacco use (to current users and current nonusers), and all questions of knowledge (to correct and not correct) for simplification of analysis. The significance level was set at P = .05.
A total of 2126 adults in the United States completed the online survey. Mean (SD; range) age of respondents was 42.0 (15.2; 18-92) years, and 30.2% of respondents were current or former smokers. Additional demographic data are given in Table 1.
Of all respondents, 66.0% considered themselves “not very” or “not at all” knowledgeable about HNC. The proportion of respondents reporting little or no knowledge about HNC did not vary significantly on the basis of tobacco use (65.8% of users and 66.1% of nonusers, respectively; P = .92) or possession of a college or university degree (64.4% vs 68.4%, respectively; P = .053). No significant differences were detected in self-reported knowledge between male and female respondents (P = .07) or between ethnic or racial groups (P = .02).
Query of respondent knowledge of the definition of HNC revealed that most respondents lacked understanding of organs or tissues involved by HNC, with nearly as many respondents incorrectly identifying brain cancer as HNC (21.0%) as throat cancer, the most common correct answer (22.1%) (Figure 1). Even fewer respondents correctly identified cancers of other sites such as the mouth (15.3%) or larynx (2.0%) as HNC. Correct identification of HNC sites was only slightly increased among respondents who identified themselves as “somewhat,” “very,” or “extremely” knowledgeable about HNC (throat, 24.4%, P = .07; mouth, 17.7%, P = .02; larynx, 3.6%, P < .001).
Questions about symptoms of HNC revealed that almost all respondents lacked knowledge of common symptoms, with only 14.9% identifying “red or white sores that do not heal” and even fewer identifying other important symptoms such as “sore throat” (5.2%), “bleeding in the mouth or throat” (0.5%), or “swelling or lump in the throat” (1.3%) (Figure 2). Headache, a nonspecific symptom that is uncommon in HNC, was the symptom most frequently identified as a symptom of HNC among survey participants (19.0%).
Knowledge of the risk of mouth and throat cancer associated with tobacco use was greater than the low knowledge of HNC signs and symptoms, with 54.5% of respondents correctly identifying smoking and 32.7% correctly identifying chewing or spitting tobacco as risk factors for mouth and throat cancer (Table 2). Survey participants with college or university degrees were more likely to identify smoking or chewing and/or spitting tobacco as risk factors (P < .001 for both), whereas those who self-identified as African American or black were less likely (P = .02 and P < .001, respectively). Current tobacco users and nonusers were equally likely to identify smoking as a risk factor (54.5% and 54.5%; P = .99); however, former smokers were more likely to know of this association than current or never smokers (61.3% vs 53.3%; P = .008). Increasing age was associated with greater identification of smoking (P < .001) and chewing and/or spitting tobacco (P = .009) as risk factors for mouth and throat cancer. Correct identification of alcohol use (4.8%) and prolonged sun exposure (0.6%) as risk factors was far lower. Respondents who consumed 4 or more alcoholic drinks per day were no more likely than those who did not to identify alcohol use as a risk factor for mouth and throat cancer (3.9% vs 4.8%; P = .74).
Whereas the majority of those surveyed identified smoking as a risk factor for mouth and throat cancer, knowledge of HPV infection as a risk factor was very uncommon at 0.8% (Table 2). When specifically queried about the association between HPV and throat cancer, 12.8% of respondents were aware of this association (Table 3). Respondents with a college or university degree were more likely to associate HPV infection with throat cancer (14.8% vs 10.0%; P = .001). Interestingly, older age was associated with greater knowledge of tobacco use as a risk factor (Table 2) but with less knowledge of HPV infection as a risk factor (P = .01) (Table 3). In contrast to the low proportion of respondents who associated HPV infection with HNC, a majority were aware of vaccines targeting HPV (70.0%) (Table 3). Greater awareness of the HPV vaccine was reported by respondents with college or university degrees (76.7% vs 60.4%; P < .001) and by women (80.6% vs 57.1%; P < .001). Awareness of HPV vaccines was not age dependent (P = .09).
Results of this survey indicate that adults in the United States have very little knowledge about HNC. Most respondents did not know which cancers make up HNC. Similarly, most respondents were unaware of common symptoms of HNC, with only 15% recognizing “red or white sores that do not heal” and fewer than 5% recognizing other important symptoms such as change in voice, bleeding in the mouth or throat, or swelling or lumps in the neck as symptoms. Because prompt diagnosis and treatment of HNC depend heavily on patient recognition and self-referral, these results suggest that increasing public awareness may affect early detection and therefore treatment outcomes.
Because environmental exposures account for the majority of HNC, it is among the most preventable forms of cancer through avoidance of exposure.9,30,31 This survey demonstrates that there is little knowledge of HNC risk factors among the general population. Data presented here are consistent with previous reports, showing that a majority (54.5%) of respondents were aware of the association between HNC and smoking32; however, these data simultaneously suggest that a large number of American adults (45.5%) lack this risk factor knowledge that could enable behavioral change. Respondent awareness of nontobacco risk factors for HNC was poor, with only 4.8% identifying alcohol use and 0.5% identifying prolonged sun exposure as risk factors for HNC. Groups at higher risk for HNC, including African Americans, tobacco users, and alcohol users, demonstrated equal or lower knowledge of HNC risk factors compared with the general population. For example, African Americans were significantly less likely to identify smoking or chewing or spitting tobacco as risk factors for HNC. Arguably, the paucity of public awareness of HNC is disproportionate to its sizeable disease burden. For example, previous work investigating public awareness of melanoma has demonstrated far superior public knowledge of risk factors, with awareness rates between 45% and 90% for various factors.33,34 According to the American Cancer Society, melanoma has incidence and mortality similar to those of HNC in the United States.1
Older respondents were more likely to be aware of the relationship between tobacco use and HNC, with 60.6% of respondents older than 65 years correctly identifying smoking as a risk factor, compared with 46.2% of adults 29 years or younger and 34.4% of adults younger than 21 years. A previous report demonstrated that 15.7% of adolescents were aware that tobacco use is a risk factor for HNC.32 These data indicate that many Americans learn of the association between tobacco use and HNC between adolescence and 30 years of age. Interestingly, the same study revealed that 82% of adolescents were aware of the association between smoking tobacco and lung cancer, indicating that most Americans learn of this association at a preadolescent age. According to the American Lung Association, which used data from the Centers for Disease Control and Prevention, 86% of adults who have ever smoked began smoking regularly at the age of 21 years or younger.35 Thus, whereas most smokers are aware of the risk of lung cancer at the time they begin smoking, they are largely unaware of the risk of HNC. The greater knowledge of the tobacco-dependent risk of HNC among former smokers indicates that this knowledge may contribute to the decision not to smoke. Therefore, improved awareness of HNC among youth may decrease the rate of smoking initiation.
Knowledge of the role of HPV as a risk factor for HNC was very poor among survey participants (0.8%). More specific queries revealed improved, but still low, awareness of the association between HPV infection and throat cancer (12.8%). Whereas the majority of respondents (70.0%) were aware of vaccines that protect against HPV infection, the lack of awareness of the association between HPV infection and throat cancer and the greater awareness of the vaccine among women suggest that this knowledge is primarily due to awareness of the role of HPV in uterine cervical cancer. Because oropharyngeal cancers are overwhelmingly attributable to type 16 HPV, available HPV vaccines should prevent oropharyngeal cancer as suggested in preliminary work.36 The Advisory Committee on Immunization Practices recommended the immunization of all adolescent boys and girls against HPV in 2011,37 but in 2012, only 53.8% of adolescent girls and 20.8% of adolescent boys had received at least 1 dose of the HPV vaccine.38 Multiple reports have shown that the incidence of oral HPV infection and HPV-related oropharyngeal cancer is 3 to 6 times higher in men than in women, indicating that current vaccination trends may not provide population protection for HNC.39,40 Approximately 13 930 cases of oropharyngeal cancer are expected to occur in 2013, 65% of which will be HPV-positive tumors.1,41 Widespread HPV vaccination could therefore prevent almost 9000 cases of oropharyngeal cancer annually. However, greater awareness of the role of HPV infection in oropharyngeal cancer is necessary to improve vaccine adherence, especially in men. In addition, greater awareness of the disease may prompt patients harboring symptoms of HPV-positive cancers to seek evaluation while also prompting dentists and physicians to consider this in the differential diagnosis of more common diseases such as pharyngitis, tonsillitis, and benign lymphadenopathy.
In 2003, the HNCA sponsored a telephone survey with similar goals for determining awareness of HNC, conducted by Harris Interactive and involving 1013 respondents (Harris Interactive; unpublished data; March 2003). Comparison of the 2003 and 2013 results demonstrates that awareness of HNC has not substantially improved. In 2003, 62% of respondents considered themselves “not very” or “not at all” knowledgeable about HNC, compared with 66% in 2013. There was similarly no substantial change in knowledge of subsites or symptoms of HNC. These data suggest that recent efforts by medical and dental societies have been insufficient to raise awareness of HNC on a national level and substantiate the need for a concerted, nationwide educational approach. However, more respondents in 2013 correctly identified use of tobacco products as risk factors for HNC than in 2003 (55% vs 42% and 33% vs 18% for smoking and chewing and/or spitting tobacco, respectively). This may reflect global tobacco control efforts, which have increased awareness of the danger of tobacco use in recent years.42 Similarly, in 2003, 26% of respondents used tobacco products, compared with 18% in 2013, mirroring national trends.43,44 Although awareness of HNC has benefited slightly as a result of this movement, it remains low in comparison to awareness of other tobacco-related diseases.45,46
There are several limitations to this study that should be considered in interpreting its results. All Internet-based surveys incur the potential for bias by excluding participants who lack Internet connections.47 All surveys can carry bias due to nonresponse, and Internet surveys are also vulnerable to this bias. As a consequence, the pool of respondents may differ significantly from the general population.48 However, the results of this survey are consistent with previously published data on HNC awareness and awareness of specific head and neck subsites.16-20,23 These results are also comparable to data from the analogous 2003 survey conducted by telephone, indicating that the methods used are reliable. Finally, because knowledge of definitions of HNC among respondents was very low, it is likely that “head and neck cancer” was an unfamiliar term for most respondents. Because this term was used to question respondents about signs and symptoms of HNC, those results should be interpreted with caution because respondents could be more knowledgeable if questioned about specific head and neck subsites.
Over the past several decades, the incidence of HNC has decreased except in the oropharyngeal subsite, where it has increased, but 5-year survival rates have only modestly improved and the proportion of cases being diagnosed in late stages of disease has remained essentially constant.10,49,50 Given that routine screening for HNC by primary care physicians is rarely performed and currently not recommended by the US Preventive Services Task Force, early detection depends on patient recognition. Similarly, primary prevention of HNC largely depends on awareness and avoidance of environmental risk factors. Public awareness of HNC is therefore necessary for both primary and secondary prevention. This report demonstrates that public awareness of HNC is lacking. Increased public education and awareness of HNC risk factors, signs, and symptoms is a critical first step to decreasing the burden of this preventable disease.
Overall awareness of HNC in the adult population of the United States is low. This lack of knowledge includes the meaning of the term “head and neck cancer” and extends to common symptoms and risk factors including tobacco use and HPV infection. Awareness of HNC is low compared with other cancers, which is concerning given the importance of risk factor avoidance and modification, as well as early patient detection, as drivers of prevention and improved outcomes.
Corresponding Author: Benjamin L. Judson, MD, Yale Otolaryngology, 333 Cedar St, PO Box 208041, New Haven, CT 06520 (firstname.lastname@example.org).
Submitted for Publication: December 30, 2013; final revision received March 19, 2014; accepted April 16, 2014.
Published Online: June 5, 2014. doi:10.1001/jamaoto.2014.867.
Author Contributions: Mr Luryi and Dr Judson had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Roser, Nathan, Moore, Day, Judson.
Acquisition, analysis, or interpretation of data: Luryi, Yarbrough, Niccolai, Reed, Nathan, Day.
Drafting of the manuscript: Luryi, Yarbrough, Judson.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Luryi, Niccolai, Judson.
Obtained funding: Day.
Administrative, technical, or material support: Roser, Reed, Nathan, Judson.
Study supervision: Yarbrough, Day, Judson.
Conflict of Interest Disclosures: Drs Yarbrough, Nathan, Roser, and Moore are board members and Dr Day is the president of the Head and Neck Cancer Alliance, which commissioned the presented survey. Dr Day is also the president of the American Head and Neck Society. No other disclosures are reported.
Funding/Support: William U. Gardner Memorial Student Research Fellowship at Yale University School of Medicine to Mr Luryi. The presented survey was commissioned by the Head and Neck Cancer Alliance and administered by Harris Interactive, Inc.
Role of the Sponsor: The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Additional Contributions: The authors acknowledge Jerry Del Gaudio, BS, MBA, Head and Neck Cancer Alliance, for his role in data acquisition and manuscript editing. He was not compensated for his contributions to this study.
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