Cancer is considered a social, economic and public health problem of the 21st century as it can psychologically affect the whole family and the quality of life. Head and neck cancer is a general term typically associated with malignancies that develop from the epithelial lining of the mucosal surfaces in the head and neck. These areas include the paranasal sinuses, nasal cavity, oral cavity, pharynx, and larynx. They are crucial parts which facilitate swallowing and respiration. Most cases are squamous cell carcinoma (SCC), which is called head and neck squamous cell carcinoma (HNSCC).
Its health concern is worldwide as its incidence and mortality rates are high. According to Global Cancer Observatory data for 2022, there were nearly 20 million newly diagnosed cancer cases and an approximately 50% fatality rate due to cancer. Based on their projections, the yearly count of new cancer diagnoses is expected to hit 35 million by 2025, representing an approximate 77% rise from the figures recorded in 2022. Within the category of head and neck cancers, the oral cavity is responsible for 2% of all cancer locations.
There are many preventative measures, primary as well as secondary, which can ward off cancer to a great extent. Public health initiatives are essential to increase screening programmes, reduce the use of tobacco, alcohol, and areca nuts (or betel nut) chewing, and promote a healthy lifestyle and eating habits. These measures can significantly reduce the incidence as well as mortality of cancer worldwide.1,2,3
There are many risk factors which lead to cancer, and they are alcohol consumption, smoking, tobacco chewing, viral infections like Human papillomavirus (HPV), Epstein-Barr virus (EBV), occupational and environmental exposures, nutritional deficiencies, genetic and epigenetic changes in the body.
Alcohol and tobacco consumption are important risk factors in the HNSCC. A UK national survey indicated that 70% of cases of oral and pharyngeal HNSCC are associated with these substances. Tobacco contains numerous carcinogenic chemicals such as polycyclic aromatic hydrocarbons, nitrosamines, aromatic amines, and aldehydes. They are released during high-temperature combustion and are known to damage DNA in the cells of the oropharynx and lead to the development of cancer. The incidence of cancer is significantly higher in smokers compared to non-smokers.
The likelihood of developing head and neck squamous cell carcinoma (HNSCC) increases with the quantity and frequency of alcohol intake, with the most significant risk seen in individuals who consume more than three alcoholic beverages daily. The risk of head and neck cancer (HNC) also differs depending on the type of alcohol consumed, showing higher risks in those who drink spirits (like whiskey or vodka) compared to beer or wine.
Alcohol acts as a solvent, heightening the vulnerability of mucosal tissues to carcinogens such as tobacco smoke or nitrites found in food. Acetaldehyde, which is formed from ethanol through the action of alcohol dehydrogenase (ADH), has been demonstrated to have mutagenic effects.
In South and Southeast Asia, areca nut (betel nut) or tobacco chewing accounts for more than half of oral and oropharyngeal cancer.1,3,4
The incidence of Human Papillomavirus (HPV) related head and neck squamous cell carcinoma (HNSCC) is rising at a concerning pace, particularly in Western nations. Serotypes 16 and 18 of HPV are the most frequently associated with head and neck cancers, particularly oropharyngeal cancer. At present, the cause of the significant rise in cases of HPV-related head and neck cancer remains unclear, although it is suggested that this trend may be linked to a growing prevalence of cancer-inducing strains of HPV.
Additionally, the Epstein-Barr virus (EBV) contributes to the development of specific types of head and neck cancers, including nasopharyngeal carcinoma. The proteins produced by the EBV genetic DNA play a role in triggering and maintaining the cancer-causing characteristics of the virus.5,6
Exposure to solvents from electrical and electronic equipment assemblers, radio, television, flame cutters, welders and printers. Some of these solvents trichloroethylene, perchloroethylene or benzene proven cancerous by the International Agency for Research on Cancer (IARC) are proven cancerous. Oral hygiene also plays an important role. It has been seen that frequent trauma from teeth was a causative factor in the development of oral cancer.7
Consumption of fruits and vegetables has been linked to a decreased risk of cancer because of their high levels of antioxidants, anti-inflammatory compounds, and immune system support. The activity of antioxidants helps lower levels of reactive oxygen species (ROS), safeguards against oxidative damage, promotes DNA repair processes, and enhances the expression of genes that produce antioxidant enzymes.8
Numerous cytogenetic and molecular studies have explored the presence of genetic changes in HNSCC, revealing that the activation of oncogenes and the inactivation of tumour suppressor genes play a role in the disease's development.
Genetic alterations, primarily involving gene amplification, mutations, and overexpression, that contribute to oncogene activation have been recorded in HNSCC, however, these studies are in the early stages and include a limited number of patients. Information regarding the connection between these genetic changes, disease progression, and patient outcomes has been inconclusive.9
Primary prevention aims to prevent cancer from ever developing. So it can be done by preventing the risk factors.
Rehabilitation programs should incorporate pharmacological support, and individuals are encouraged to engage with a psychotherapist. Sustaining abstinence is frequently challenging, so healthcare professionals should observe the patient for some time. Public health workers ought to implement awareness initiatives, organise campaigns, and facilitate wellness check-ups and screenings. Awareness programs for areca nut cessation should be organised by examining the cancer-causing potential of tobacco use and its impact on oral health.
HPV vaccine is recommended, especially in protecting against HPV types 16 and 18.
Dietary factors include improving food by incorporating foods rich in antioxidants and vitamins A, E, and C. Red meat can cause cancer related to the intestine, so it must be consumed cautiously.
Secondary prevention is carried out when the signs and symptoms of carcinoma are present and early intervention is made to improve the prognosis and reduce the mortality. Screening programmes are conducted worldwide to detect cancer at a very early stage.
In the case of oral cancer, some premalignant lesions appear in advance, so if those individuals are given proper treatment at that time, then oral cancer can be prevented. Biomarkers such as salivary biomarkers can detect cancer and are non-invasive. Other minimally invasive biomarkers are also tested on the biopsied sample to make a diagnosis.1
Innovative methods should be advocated for cancer detection, and new therapies like targeted therapies and immunotherapies should be developed. Drug resistance and metastasis (tumour spreading to secondary sites) have often been hindrances to the proper cure for cancer. New diagnostic and prognostic markers should be formulated to minimise these challenges.10
Head and neck squamous cell carcinoma (HNSCC) has increased significantly in the past few years. It affects the quality of life of the individual as well as family members, both financially and psychologically. Preventative measures can significantly lower cancer rates. Public health initiatives promoting screening, reducing tobacco and alcohol use, and encouraging healthy lifestyles are crucial. Risk factors for head and neck cancer include alcohol and tobacco use, which are linked to most oral and pharyngeal HNSCC cases. Tobacco contains harmful chemicals that can damage DNA, increasing cancer risk. The likelihood of developing HNSCC rises with higher alcohol consumption.
Human Papillomavirus (HPV) is increasingly associated with head and neck cancers. HPV types 16 and 18 are commonly linked to these cancers. The Epstein-Barr virus (EBV) also plays a role in specific head and neck cancers, such as nasopharyngeal carcinoma. Occupational and environmental factors contribute to cancer risks, as do dietary habits. A diet rich in fruits and vegetables may lower cancer risk due to antioxidants. Genetics also play a role in HNSCC, with research showing genetic changes that might influence cancer development. Primary prevention efforts include tobacco and alcohol cessation programs and HPV vaccinations.
Nutritional improvements are also encouraged. Secondary prevention focuses on early detection through screening, allowing for timely interventions. Biomarkers, including salivary ones, can help in early diagnosis. Challenges in cancer treatment include drug resistance and tumour spread. Future approaches should emphasise innovative detection methods and the development of targeted therapies and new diagnostic markers.
