Aim: An overview and comparative evaluation of head and neck cancer risk factors in India and Australia. Method: In this review we included articles with information on head and neck cancer risk factors and its association based on: smoking tobacco, alcohol, smokeless tobacco, betel nut and areca nut chewing, viral infection like HPV, dental hygiene, diet, family history, socioeconomic status, other heavy metals and systemic conditions. Articles with clinical features, diagnosis, treatment and prognosis were excluded. Results: Head and neck cancer in India has different demographic, risk factors, dietary habits, personal and family history. Oral cancer is more common amongst all head and neck squamous cell cancers in males. This is mainly attributed with consumption of a variety of smokeless tobacco, smoking, alcohol, poverty, illiteracy, cultural, advanced stage at presentation; lack of good treatment infrastructure creates main challenge to India as compared to Australia. Conclusion: The knowledge about risk factors for HNC in public health education for general population supports health promotion and tobacco prevention, which is the main aim of the programs started by the government, as head and neck cancers are potentially preventable.
Worldwide, the head and neck cancer (HNC) is the 6th most common cancer; as it is considered a lethal disease affecting the upper aero-digestive tract and near about 0.9 million new cases have been diagnosed each year [
The incidence of HNC seems to be 12.3 per 100,000 in Australia and 22 per 100,000 population in India, also accounts for about 30% of all types of Indian cancers [
Most of the HNC cases and deaths are due to the cigarette smoking and alcohol consumption in the global population, which are the major risk factors, along that it has synergistic effect in increasing oral cancer risk whereas smokeless tobacco (SLT), betel nut, and human papilloma virus are etiological agents responsible for it in the Indian population [
In India, nearly two-thirds of patients present with advanced stages [
Major aim of this article is comparative evaluation of published data about the prevalence of risk factors for head and neck cancer in India and Australia.
We collected data from published literature by carried out a organized search using key words with risk factors, tobacco, alcohol, betel nut chewing, human papilloma virus, environmental factors and other risk factors for HNC from Medline, Pubmed and Google Scholar using a combination of subject headings and keywords.
In this review we included articles with information on head and neck cancer risk factors and its association based on; smoking tobacco, alcohol, smokeless tobacco, betel nut and areca nut chewing, viral infection like HPV, dental hygiene, diet, family history, socioeconomic status, other heavy metals and systemic conditions.
We selected the articles carefully after reading abstract and titles to determine whether, they were completely fitted the inclusion criteria for the review. In addition to this, we also studied the references of related articles to find more literature. Articles with clinical features, diagnosis, treatment and prognosis were excluded.
Tobacco is deadly in any form and its use already has become responsible for more than 6 million deaths worldwide each year. According to the World Health Organization (WHO) estimates, globally, there were 100 million premature deaths due to tobacco in the 20th century, and if the current trends of tobacco use continue, this number is expected to rise to 1 billion in the 21st century [
In India tobacco smoking in the form of cigarettes, bidis, cigars/chutta/cheroot, dhumti (Goa), the water pipes/hookah (north India), reverse chutta smoking (in coastal regions in Andhra Pradesh and Orissa), hookli (Gujarat) and chillum (northeastern parts of India). Estimates indicate 57% of men and 11% of women between 15 - 49 years of age use some form of tobacco and an estimate of the Global Adult Tobacco Survey (GATS) conducted during 2009-10 indicate that 34.6% of the adults (47.9% males and 20.3% females) are current tobacco users. 14% of the adult smoke (24.3% males and 2.9% females) and similar number of students, whereas in Australia daily smoking rate for smokes is 17% in 2007 and around 70% of laryngeal cancers are attributed fully or in part to tobacco smoking [
Studies on bidi smoking, the most common form of tobacco smoking in India, provide a strong association of bidi smoking with risk of developing cancer is 5 - 9 times greater than for nonsmokers at various sites, such as oral cavity, pharynx, and larynx, which is further multiply about 17 times for heavy smokers of 80 or more per day [
Many different forms of smokeless tobacco are used in India, which are very popular in large number of people. Among them, the use of betel quid chewing (pan) is extremely widespread in many regions of India. Along with this, gutka, khara, mawa, zarda, and khainni, are mixes by vendors and are all dry mixtures of areca nut flakes, lime, tobacco power [
About 10% of the world’s population chews betel quid regularly and most prevalent in Asia-Pacific region but use of betel quid is not quite relevant to Australia [
Australian immigration statistics show that 30% of new arrivals in Australia (New South Wales) are from Indian subcontinent, China, and Taiwan, are more likely to be responsible for this tradition of tobacco chewing, as they are closely connected to sociocultural and religious activities long after they migrate to Australia [
Drinking alcohol on regular basis is an important risk factor for HNC and it is associated with an increased risk, which is dose-dependent. A regular consumption of 4 - 5 drinks daily, increase oral cancer risk by 2 - 3 folds than non-drinkers but, in case of heavy alcohol drinking risk increase up to 7% to 19% oral cavity cancer [
The consumption of alcohol was very high in India; in 2016 11.4 L per capita per year with age above 15 years old and among them 30% are regular and 11% moderate to heavy drinker. However, the consumption is very high in the Northern Territory: approximately 15 L and New South Wales 13 L of pure alcohol per year have been consumed by adults (≥15 years old) [
Taking alcohol in combination with tobacco in any form further enhances risk of oral cancer by 11 times [
The human papilloma virus (HPV) has been identified as an etiological factor in HNC mainly oropharyngeal cancer [
HPV-16 is the most common genotype, occurring in 90% of high risk HPV oropharyngeal carcinomas [
Within Australia, 8844 cases of HPV-related oropharyngeal cancers were diagnosed between 1982 to 2005. This particular study reported that the incidence of HPV-related cancers significantly increased annually among both males (1.42% per annum) and females (1.04% per annum) P value < 0.01 [
Increase in incidence found with use of newer techniques that could be helpful for 45% (26 of 57) of tumors tested were positive for P16 in patients from the Northern Territory in Australia; however, 63% of those were Indigenous Australians [
The vaccination of HPV has not been incorporated in the national immunization program of India. There is dispute about using the HPV vaccine in Australian men; it is currently indicated for use in young women. In Australia, the current HPV vaccination program for females aged 12 to 13 years was introduced in 2007 and may have an effect on the future incidence of these cancers [
Poor oral hygiene also causes oral cancer. In one study, more than 85% of oral cancer patients had poor oral hygiene [
However, In India oral precancerous conditions are also prevalent which are helpful in diagnosing majority of oral cancer cases and exclusively present in tobacco users.
Oral lesions that have been identified clinically as having potential for malignant conversion include leukoplakia, erythroplakia, lichen planus, and submucous fibrosis. Reported rates of malignant transformation of leukoplakia range from less than 1% to 18% [
Ultraviolet (UV) light exposure may cause HNC, particularly lip cancer, is mainly caused by UVB (290 - 320 nm) irradiation due to increased exposure of the mucosal linning of the lips to the sun and cancer in the lower lip occurs in around 90% of all cases [
In Australia, more than 50% of HNC in white people are located on the lip. [
In Western Australia annual incidence of lip cancer was 8.9 in 100,000 and 2.7 in 100,000 for males and females, respectively, from 1982 to 2006 [
Different studies in last few years showed diet has come into view as a risk factor of HNC along with tobacco smoking, alcohol intake and HPV [
According to the UN report published in 2017, India is home to 190.7 million underfed people, 51% women are anemic and more than 50% of elderly people of India are suffering from malnutrition but there is hardly any published quantitative data on the nutritional status of Indigenous Australians. Prevalence of malnutrition in Australia was reported at 2.5% in 2015, on average, daily smoking rate 3 times more in the lower socioeconomic group then higher [
India is classified as a lower-middle-income group country by the World Bank. 90% of the oral cancer patients in rural areas belong to the lower or lower-middle socio-economic class, and 3.6% are below the poverty line based on Pareek’s classification [
Brookes reported a significant difference between the survival of undernourished HNC patients (7.5% at 2 years) and the survival of adequately nourished patients (57.5% at 2 years) undergoing radiotherapy [
Genetic susceptibility might play a role in the progression of cancer, but those that have revealed a high risk for HNC with respect to family history of cancer. A first-degree relative is a family member who shares about 50 per cent of their genes with a particular individual in a family beside this a higher risk of oral cavity cancer in males with a family history of smoking-related cancers than in females [
The prevalence of the p53 mutation is 81% in the Western world but rare in India. Multiple genetic abnormalities are common in head and cancers in India and Southeast Asia. These include a prevalence of Ha-ras mutations (35%), loss of heterozygosity of Ha-ras (30%), N-ras amplification (28%), and N-myc amplification (29%) [
Environmental and occupational factors including asbestos, wood dust and leather dust can also contribute to some HNC, including in the larynx and pharynx [
In India large number of population dealing with Plummer-Vinson syndrome is associated with a high risk for development of carcinoma of oral cavity, oropharynx and esophagus [
Immunosuppressive conditions increase risk of developing oral cancers in a number of patient undergone kidney transplantation, lip cancer in patients suffering from AIDS oral carcinoma has been reported [
Australian diabetic patients consistently seemed to be more likely to have distant metastases of cancer at the time of diagnosis and it is involved as a risk factor not only for the development of HNC but also for oral premalignant lesions such as leukoplakia [
This review gives an idea that major risk factors are lifestyle, behavioral and environmental associated in developing various HNC in population of India and Australia.
In India, the illiteracy, lack of infrastructure and health care facilities, are major problems. Lack of awareness is more common in the lower socio-economic class about the side effects of tobacco, and prevalent cultural beliefs lead to delay in seeking treatment and result in advanced-stage presentation of disease. People in Australia more aware about symptoms and government provide better cancer treatment facilities and early diagnosis and treatment.
The knowledge about risk factors for HNC in public health education for general population supports health promotion and tobacco prevention programs by the government, as HNC are potentially preventable.
The authors declare no conflicts of interest regarding the publication of this paper.
Singh, S.P., Eisenberg, R. and Hoffman, G. (2018) An Overview and Comparative Evaluation of Head and Neck Cancer Risk Factors in India and Australia. International Journal of Otolaryngology and Head & Neck Surgery, 7, 254-267. https://doi.org/10.4236/ijohns.2018.75027