Cancer, in short, is an abnormality of the functioning of a cell that causes uncontrolled multiplication of cells that have lost their purpose. This compromises surrounding healthy cells and eventually cancer cells can enter the blood and lymph systems to spread to other parts of the body. 

Head and neck cancer is a diverse group of cancers originating in the head and neck that make up the 5th most common site of cancer development. The head and neck is made up of the number of sites and interestingly, brain and eyeball cancers are excluded from this list. 

The most common sites affected by cancer in the head and neck are the skin, thyroid gland, mouth, larynx (voice box) and oropharynx (part of the throat at the back of the mouth). Other parts of the head and neck include the salivary glands, nasal cavity and sinuses, conjunctiva of the eye, and the rest of the pharynx (throat) including the nasopharynx (back of the nose) and hypopharynx (next to the larynx). 

The most common type of head and neck cancer is squamous cell carcinoma. This is the flat surface cell making up the skin and mucosa (“skin” of the nose/sinuses, mouth, pharynx and larynx) exposed to our environment. This type of cancer is mostly caused by the sun, smoking, alcohol and certain viruses. 

We are all on a spectrum of susceptibility to these carcinogens (cancer causing substances) and all know people who have smoked their whole lives without getting cancer. Unfortunately people who have never smoked may also get a smoking related cancer. Alcohol on its own is a carcinogen but the effects are multiplied, not added, when combined with smoking. Our genetics also influence our susceptibility, but on their own they are seldom a cause in the head and neck. Stopping the carcinogen exposure before cancer develops reduces the risk of getting a future cancer. It is also important that if head and neck cancer is diagnosed then the relevant carcinogen should be stopped, because this affects the chances of whether this cancer can be beaten or whether there is another cancer elsewhere that develops.

The human papilloma virus (HPV) which causes cervix cancer in women can cause cancer in the oropharynx and this cancer is on the increase worldwide. This is the most common sexually transmitted disease and is believed to be contracted early in one’s sexually active years. Why it causes cancer in some people and not others is not well understood. Worldwide pre-sexually active girls are vaccinated against HPV to prevent getting cervix cancer in later adulthood and there is a push too to vaccinate boys to prevent oropharynx cancer as well as penis and anal cancer.

To summarise, the best lifestyle habits to decrease the chance of getting head and neck cancer are to wear sunscreen daily, avoid smoking and alcohol and not have sex outside of wedlock.