Overview

Tonsil cancer is the most common form of oropharyngeal cancer under the umbrella term of head and neck cancer. The tonsils are classified as two glands at the back of the throat just behind the mouth in an area called the oropharynx.¹

They work as a form of first defence for the immune system by working to reduce infection by stopping harmful bacteria entering through the mouth and nose. It is sometimes professionally referred to as squamous cell carcinoma depending on the type with a small number being lymphomas. Cancer research UK has reported a 35% increase in head and neck cancer incidences since the early 1990s.⁴ Research has suggested that its incidence rate is rapidly rising due to the increasing prevalence of the human papillomavirus (HPV).²

Tonsil Cancer 

Anatomy of the tonsils:

The tonsils are two oval-shaped masses found at the back of the throat just behind the soft palate, one on each side. Their size can vary from person to person but an average study explained the overall average to be 42.81 cm³.³

Due to their high concentration of white blood cells, the tonsils are an integral part of the immune system's primary defense system which work to stop bacteria entering through the mouth and nose, similar to the lymph nodes. The initial symptoms of tonsil cancer can sometimes appear to be mild but always consult a healthcare professional to be sure, if you are concerned. 

Symptoms of Tonsil cancer:

• Persistent sore throat that won't seem to go away
• One tonsil appears more swollen than the other for no obvious reason
• Blood in your saliva
• Excessive difficulty swallowing, eating or speaking
• Bad breath (halitosis)
• Unexplained mouth pain
• Swollen lymph nodes in the neck
• Ear pain
• Sores in the back of the mouth that don't appear to be healing

Types of tonsil cancer

There are two types of tonsil cancer with the most common being squamous cell carcinoma (SCC). SCC is the second most common form of skin cancer characterised by its accelerated growth of abnormal squamous cells - the flat cells near the surface of the skin that constantly shed as they are replaced by new ones. 

The second type is less common and is called primary tonsillar lymphoma (most commonly a form of non-hodgkin lymphoma).⁵  The symptoms tend to be the same as squamous cell carcinoma but can also include a fever, unexplained weight loss and frequent night sweats. 

Both types require various tests to diagnose and differentiate between the two, most commonly a lymph node biopsy or bone marrow testing. 

Risk factors for tonsil cancer

There are the commonly known risk factors that increase the likelihood of developing cancer that are generally well known, such as smoking, and excessive drinking: Cancer research UK published that around 17% of mouth cancers in the UK are caused by smoking and 35% from drinking alcohol. There are other risk factors that can influence the chances of developing tonsil cancer but unfortunately sometimes people can develop tonsil cancer despite not having these risk factors. 

Demographics 

The most common age range for developing a type of head or neck cancer is between the ages of 65 to 69 years meaning those over the age of 65 are already at an increased risk. There also appears to be a higher risk in males with Cancer Research UK reporting 31% of head and neck cancer cases being female and 69% as male. This could be for many reasons such as a historically higher likelihood of men to drink excessively and smoke which are key risk factors for developing tonsil cancer. 

Those with a family history of cancer or genetic mutations are also at an elevated risk so are recommended to discuss any concerns with their healthcare professionals and avoid smoking and drinking excessively.³

Human papillomavirus (HPV) and Tonsil cancer

This extends further to those with a pre-existing weak immune system as they are more likely to develop diseases such as human papillomavirus (HPV). HPV is one of the most common sexually transmitted infections and can spread through direct contact to the affected areas such as the mouth or throat. It is reported that around 80% of people will be infected with HPV at some point in their lifetime with it causing no harm in most cases and many recovering without any medical intervention. 

HPV infects the epithelial cells of the tonsils, integrating into the DNA which can lead to the growth of abnormal cell masses and eventually tonsil cancer. HPV-16 in particular is the biggest driver of HPV-positive tonsil cancers and tends to be diagnosed at a later stage due to its subtler symptoms. However, HPV-positive tonsil cancers tend to have a better overall prognosis than HPV-negative tonsil cancers as they appear to respond better to treatments such as surgery and radiation. 

Epidemiology 

The impact of HPV 

Many studies have shown an increase in the prevalence of tonsil cancer, more specifically squamous cell carcinoma, at an unprecedented level in both older and younger populations. In 2023 a paper reported it as the sixth most common cancer globally, with the rate rapidly increasing in the last 40 years.^2,6 

This significant rise has been solely attributed to the rise of HPV infections, especially in western populations, so much so that the WHO classification of squamous cell carcinoma tonsil cancers now has two subdivisions - HPV negative and HPV positive. 

This follows as HPV positive tonsil cancer has been reported as more common in younger non-smoking patients, both male and female whilst HPV-negative tonsil cancer is more common in older male patients with a history of smoking. This difference in demographics demonstrates the impact of HPV on the risk factors of developing tonsil cancer and it has transformed the way tonsil cancer is diagnosed and treated globally.

In efforts to reduce these rising figures, especially in younger people the HPV vaccine was developed to help prevent cervical or reproductive cancers, it may also aid in preventing oropharyngeal cancers.⁷ It is given mainly to children between the ages of 11 and 12 and is not recommended for those over the age of 26. 

Educating the public 

Spreading awareness of this increase in HPV related tonsil cancer is essential in damping its increasing appearance in younger patients. This is mainly because educating the public about safer sex practices and preventing HPV transmission can help reduce infection rates, therefore reducing HPV-positive tonsil cancers. 

FAQs

Are particular ages at a higher risk of developing tonsil cancer?

Historically men over the age of 65 with a history of smoking and excessive alcohol consumption were at the highest risk and this stands in cases of HPV-Negative tonsil cancers. However, in recent decades there has been an increase in HPV-positive tonsil cancers which are more common in younger, non-smoking people. 

This means that cultural factors now play a role in determining who is more likely to develop tonsil cancers but there are those with an increased risk. 

What impact has HPV had on tonsil cancer prevalence?

HPV, or human papillomavirus, has massively impacted the prevalence of tonsil cancer, especially in younger non-smoking generations. So much so that there is a medical distinction between HPV-positive and HPV-negative tonsil cancers with HPV-positive cancers specifically being on the increase globally. The demographic of men over 60 who smoke being at the highest risk has now extended to include younger people with weakened immune systems as they are at a higher risk of catching HPV as it is one of the most common sexually transmitted diseases globally. 

What are some of the symptoms of tonsil cancer?

This list is not exhaustive but can include: 

• A persistent sore throat that won't seem to go away
• One tonsil appears more swollen than the other for no obvious reason
• Blood in your saliva
• Excessive difficulty swallowing, eating or speaking
• Bad breath (halitosis) 
• Unexplained mouth pain
• Swollen lymph nodes in the neck
• Ear pain
• Sores in the back of the mouth that don't appear to be healing

Summary 

Tonsil cancer is a form of head and neck cancer with symptoms often including a persistent sore throat and difficulty eating and swallowing. It affects the tonsils which are found behind the soft palate on either side of the throat. 

It has been historically more common in men over the age of 60 who have a history of smoking and drinking alcohol, however this demographic has extended in recent decades especially in western countries. Tonsil cancer occurrence is on the rise globally with recent decades having shown an unprecedented increase of tonsil cancer diagnoses in younger non-smoking patients due to the sexually transmitted disease human papillomavirus (HPV). HPV-positive tonsil cancers now make up 60 - 70% oropharyngeal cancers in the US according to the CDC demonstrating the impact of HPV on the epidemiology of tonsil cancers. It has drastically changed the way tonsil cancers are diagnosed and treated in modern days. Prevention via education and vaccinations are in effect with hopes to reduce these rising figures.