Mouth Cancer

Mouth cancer, also called oral cancer, starts anywhere in your mouth, including your lips, inner cheeks, gums, floor or roof of the mouth.

Cancers that start on the tongue and middle of the throat (oropharyngeal cancer) are closely related to mouth cancer. These are covered in detail in separate pages on this site.

This page provides an overview of the main types of mouth cancer, including risk factors, symptoms, diagnosis, treatment, and how to support your body during treatment.

Mouth cancer is the most common type of head and neck cancer. It starts when tumours form in the thin, flat cells that line smooth tissue in or on your [1]:

• Lips
• Gums
• Inner cheeks
• Palate (hard and soft parts of the roof of your mouth)
• Floor of your mouth
• Tongue

Without treatment, mouth tumours can grow and spread to deeper tissues or other parts of your mouth or body.

Mouth cancer accounts for about 85% of all head and neck cancers [2]. It’s the 12th most common cancer in men and the 18th most common cancer in women [3].

Rates vary globally and are driven by risk factors like tobacco, alcohol use, and Human Papillomavirus (HPV) for mouth cancers, and sun exposure for lip cancers. India, China, and the US have the highest number of oral cancer cases [3].

Mouth cancer survival rates vary depending on where in the mouth the cancer starts and whether it has spread. As with all cancers, early detection of mouth cancer improves outcomes.

Doctors aren’t certain what causes mouth cancer, but these things increase the risk [1]:

• Long-term tobacco use (smoking and chewing)
• Drinking large amounts of alcohol
• Human Papillomavirus (HPV) infection increases the risk in younger people
• Being over 40
• Prolonged sun or ultraviolet light exposure to the lips
• Eating an unhealthy diet low in fruits and vegetables

Some people develop mouth cancer without having any clear risk factors.

Symptoms can vary by person and depending on where the cancer starts. They can include [1]:

• Mouth or tongue sores that don’t heal within a few weeks
• Red or white patches in your mouth
• Lumps in your mouth or on your lips
• Mouth pain, numbness, or discomfort
• Difficulty chewing or swallowing
• Ear pain
• Unintentional weight loss

Early mouth cancer might not cause any symptoms, and it’s easy to go unnoticed. Dentists often detect early tissue changes which might signal oral cancer, so it’s vital to get regular dental exams.

You should also check your mouth at home. Look for any unusual sores on your lips, gums, cheeks, or tongue, and feel for lumps or bumps in your mouth or on your neck. Tell your doctor if you find anything suspicious.

Your dentist or doctor may refer you to a specialist for an oral cancer screening and further testing, which might include:

• Biopsy - A small tissue sample of the suspicious area to test for cancer
• Imaging tests - An ultrasound, CT, or MRI can get detailed pictures of your mouth, head, or neck
• A fine needle aspiration - This tests for cancer cells in a tumour or nearby lymph nodes.

If you’re diagnosed with mouth cancer, doctors will stage and grade it to guide your treatment plan.

Staging describes how large a tumour is and whether it has spread to lymph nodes or other parts of your body [4].

• Stage 0 - Cancer cells in the top layer of the mouth or lip tissue only
• Stages I and II - Small tumours confined to the mouth or lip tissue
• Stage III - A larger tumour that has spread deeper or to one nearby lymph node
• Stage IV - Advanced cancer that has spread into multiple lymph nodes or other parts of your body

Grading refers to how cancer cells look under a microscope compared with healthy cells, which helps predict how quickly or aggressively they will grow and spread.

• Grade 1 cells resemble healthy cells and are likely to grow slowly.
• Grade 2 cells look less normal and can grow at a medium-fast rate.
• Grades 3 and 4 (high-grade) cells appear highly abnormal and are likely to grow and spread quickly.

Treatment for oral cancers depends on the location, stage and grade of the cancer. It might include one or a combination of:

• Surgery to remove the tumour and any nearby tissues. You might also need reconstructive surgery if your doctor removes bone or tissue from your lips, tongue, or other places in your mouth.
• Radiotherapy, which uses high-energy radiation to kill cancer cells
• Chemotherapy, which uses strong medicines to kill cancer cells and shrink tumours.
• Targeted therapy and immunotherapy, to target cancer cells or help your immune system detect and kill them.

Surgery or radiotherapy can affect your swallowing, eating, speech or physical appearance. Reconstructive surgery and rehabilitation programs, such as speech and swallowing therapy, are also important parts of treatment that help protect your health and quality of life.

Your recovery and long-term outlook depend on many factors, including the stage, location, treatment type, and your overall health. Cancers found and treated early often have much better outcomes and higher survival rates.

Many people live long lives after mouth cancer treatment. Your doctor can give you more information about what to expect for your specific situation.

Mouth cancer treatment can take a toll on you physically and emotionally. Rest, nutrition and hydration, good oral hygiene, gentle exercise, and supportive emotional care all play a role in treatment and recovery.

Nutrition is especially important as it helps maintain your strength and energy and promotes healing. However, some mouth cancer treatments may cause these or other side effects which make it hard to eat:

• Mouth, tongue, or jaw pain
• Mouth sores
• Dry mouth
• Difficulty chewing or swallowing
• Taste changes, especially a metallic taste

These side effects can increase the risk of malnutrition. An oncology dietitian can work with you to ensure you get the calories, protein, and other nutrients you need during treatment and recovery. They may recommend:

• A soft or liquid diet that includes soups, smoothies, yoghurt, puddings, or scrambled eggs.
• Medical nutrition or oral nutrition supplements, which pack a large amount of calories and protein in a small, easy-to-consume volume.
• If you cannot meet your nutritional needs by mouth, your healthcare team may recommend tube feeding. Nutrition can be delivered through a tube passed through the nose into the stomach or, when longer-term support is expected, through a tube placed directly into the stomach. The most appropriate option depends on your treatment, swallowing ability and expected duration of support.