Health professionals are encouraging people to familiarise themselves with the early warning signs of mouth cancer, amid concerns about rising diagnoses and a lack of public awareness.
Mouth cancer, also known as oral cancer, can develop in several areas, including the tongue, gums, lips, inner cheeks and other tissues inside the mouth.
Figures highlighted by the Oral Health Foundation suggest that cases have more than doubled over the past two decades in the UK, with increases also being reported among younger adults.
Despite this, research suggests many people are unfamiliar with the symptoms and may overlook changes that deserve medical attention.
Experts say recognising unusual changes early and seeking professional advice can make an important difference.
What are the early warning signs of mouth cancer?
According to dental professionals and cancer awareness organisations, several symptoms can indicate that something is wrong.
These signs do not necessarily mean someone has cancer, but persistent or unexplained changes should be assessed by a healthcare professional.
1. A mouth ulcer that does not heal
One of the most important warning signs is an ulcer that remains present for more than three weeks.
Ordinary mouth ulcers usually heal on their own within a relatively short period, but an ulcer that persists, particularly on the tongue or gums, may require further investigation.
Some concerning ulcers are painless, meaning people may not realise anything serious is happening.
Dentistry expert Dr Victoria Sampson has warned that a persistent, painless ulcer on the tongue can be an important sign of oral cancer.
However, people should not wait three weeks before seeking help if an ulcer appears particularly unusual or concerning.
2. Red or white patches inside the mouth
Another potential warning sign is the appearance of unexplained red or white patches on the tongue, gums or lining of the mouth.
These changes can have several causes, including irritation and other non-cancerous conditions.
However, some persistent patches may represent changes to the tissue that require professional examination.
Anyone who notices a patch that does not disappear or changes over time should speak with a dentist or doctor.
3. Unusual lumps or swelling
A lump, thickening or unexplained swelling inside the mouth, on the lips or around the neck can also warrant investigation.
Swelling in the neck may sometimes involve lymph nodes, which can enlarge for many reasons, including infections.
However, a persistent or unexplained lump should not be ignored, particularly if it grows or is accompanied by other symptoms.
4. Difficulty swallowing
Persistent difficulty swallowing, sometimes described as feeling that food is getting stuck, can be associated with cancers affecting the mouth or throat.
People may also experience discomfort when swallowing or notice that eating has become more difficult.
There are numerous other explanations for swallowing problems, but new or worsening symptoms should be assessed.
5. A persistently hoarse voice
Changes to the voice, including hoarseness that does not improve, may sometimes be associated with cancers affecting the throat or nearby structures.
Hoarseness is often caused by infections, irritation or vocal strain, but a persistent unexplained change deserves medical attention.
This symptom is not specific to mouth cancer and may be more closely associated with conditions affecting the larynx or throat.
Woman recalls overlooking a symptom before cancer diagnosis
Karen Liesching-Schroder has shared her experience of initially dismissing a change inside her mouth that later turned out to be tongue cancer.
She first noticed an ulcer on her tongue that failed to heal.
Over time, the affected area became significantly worse, but she did not initially recognise that the problem could be cancer.
Her experience highlights why healthcare professionals encourage people to seek advice when something in their mouth remains unusual or does not improve.
Although most mouth ulcers are harmless, persistent changes should not automatically be dismissed.
Why are mouth cancer cases increasing?
Mouth cancer is associated with several established risk factors, including tobacco use and alcohol consumption.
Human papillomavirus, commonly known as HPV, is another important risk factor, particularly for cancers of the oropharynx, which includes the tonsils and base of the tongue.
HPV-related oropharyngeal cancers are often discussed alongside mouth cancers, although they are medically distinct from cancers arising within the oral cavity.
The disease can affect people who do not smoke or drink alcohol, and it is not restricted to older adults.
According to estimates from the American Cancer Society, more than 60,000 people in the United States are expected to be diagnosed with cancers of the oral cavity or oropharynx in 2026.
However, the reasons behind changing diagnosis rates vary between populations and cancer types, so not every increase can be attributed to the same cause.
Experts warn that public awareness remains low
Research highlighted by the Oral Health Foundation suggests that fewer than one in three adults have ever checked their mouths for unusual changes.
Approximately half of those surveyed also struggled to identify even one possible symptom of mouth cancer.
Dr Catherine Brady, President-Elect of the Oral Health Foundation, has urged people not to dismiss changes simply because they appear minor or do not cause pain.
She emphasised that most unusual findings will not turn out to be cancer, but only an appropriate professional assessment can establish what is causing them.
Brady also clarified that the commonly mentioned three-week guideline specifically concerns ulcers that have not healed.
Anyone experiencing another worrying change should seek advice promptly rather than waiting for an arbitrary period.
How to check your mouth for unusual changes
The Oral Health Foundation recommends becoming familiar with the normal appearance of your mouth so that changes are easier to recognise.
A simple self-check can be carried out using a mirror and good lighting.
Self-checks do not replace routine dental examinations, and they cannot reliably diagnose cancer.
However, they may help people recognise changes worth discussing with a professional.
When should you see a dentist or doctor?
Anyone who notices a persistent mouth ulcer, unexplained patch, lump or other concerning change should contact a dentist or doctor.
In particular, an ulcer that has not healed after three weeks should be assessed, even if it is painless.
Other concerning symptoms should be checked sooner rather than waiting for the three-week mark.
If a dental appointment is unavailable, the Oral Health Foundation recommends contacting a GP instead.
Many symptoms have harmless explanations, but identifying serious conditions at an earlier stage can improve the range of treatment options available.
The central message from health professionals is that mouth cancer awareness matters at every age, and people should feel comfortable seeking advice whenever something does not seem right.
