Oral Neoplasm

Oral neoplasm, also known as mouth cancer or oral cavity cancer, affects the lips, tongue, gums, and other parts of the mouth. Early detection can make a significant difference in treatment success, but many cases are discovered only in later stages.

Table of contents

• What is Oral Neoplasm?
• Areas of the Mouth Affected
• Who is Affected
• Causes and Risk Factors
• Signs and Symptoms
• Diagnosis
• Treatment Options
• Prognosis and Survival
• Prevention
• Living with Oral Cancer

What is Oral Neoplasm?

Oral neoplasm is a disease in which cancer develops in the lips or mouth^[1]. The oral cavity, which refers to the mouth, includes the lips, gums, tongue, the lining inside the cheeks, the floor of the mouth under the tongue, and the roof of the mouth^[2]. Most oral cancers start in flat, thin cells called squamous cells that line the inside of the lips and oral cavity. Cancers that start in these cells are called squamous cell carcinomas^[1].

Oral cancer is the sixth most common cancer worldwide, with a high prevalence in South Asia^[16]. In the United States, oral cancer accounts for roughly three percent of all cancers diagnosed annually, or about 54,000 new cases in 2022^[3]. In 2020, 45,703 new cases of oral cavity and pharynx cancer were reported in the United States, and 10,835 people died from this cancer^[5].

Oral cancer is a type of head and neck cancer. It is the most common form of head and neck cancer^[2]. The disease can look like a common problem with your lips or in your mouth, such as white patches or sores that bleed. However, the key difference between a common problem and potential cancer is that these changes don’t go away^[2].

Areas of the Mouth Affected

Oral cancer can develop in several specific areas within the mouth. The oral cavity begins at the lips and extends backwards to the front part of the tonsils^[4]. The affected areas include:

• The lips, beginning at the border between the skin and the lips
• The gums (also called gingiva)
• The lining of the inside of the cheeks (called buccal mucosa)
• The front two-thirds of the tongue
• The floor of the mouth (the part under the tongue)
• The roof of the mouth, including the hard palate (the bony front portion) and soft palate (the muscular back portion)
• The retromolar trigone (the small area behind the wisdom teeth)

The mouth is covered by a lining called the oral mucosa, which is made up of squamous cells. The structures in the mouth help you speak, taste, and chew^[6]. Cancers most commonly develop on the tongue, floor of mouth, and lower lip^[15].

Who is Affected

Oral cancer most often occurs in people over the age of 40 and affects more than twice as many men as women^[3]. The average age of those diagnosed with oral cancer is 63, though just over 20% of cases occur in patients younger than 55^[1].

Men are more likely than women to develop oral cancer. Overall, about 11 people in 100,000 will develop oral cancer during their lifetime^[2]. These cancers were most commonly diagnosed in men, occurring almost three times more often in men than in women. Among men, the highest rates of new cancers were seen in non-Hispanic White people and non-Hispanic American Indian and Alaska Native people^[5].

People who are white are more likely to develop oral cancer than people who are Black^[2]. The death rate was almost three times higher among men than women, with the highest death rates seen in non-Hispanic white men and non-Hispanic black men^[5].

Causes and Risk Factors

Oral cancer starts when normal squamous cells become cancerous after their DNA changes and cells begin growing and multiplying. Over time, these cancerous cells can spread to other areas inside of your mouth and then to other areas of your head and neck or other areas of your body^[2].

Most cancers in the mouth are related to tobacco use, drinking alcohol, or both^[3]. About 75% of people who develop oral cancer have specific habits that increase their risk^[2]. The main risk factors include:

• Tobacco use: Using any kind of tobacco, including cigarette, pipe, and cigar smoking, as well as chewing tobacco and other smokeless tobacco products, puts you at risk for developing oral cancers^[1]. Tobacco use of any kind, including electronic cigarettes, chewing tobacco, and snuff, increases the risk^[3]. According to the Mouth Cancer Foundation, 90% of oral cancer patients are tobacco users^[18].
• Alcohol use: Heavy alcohol use increases the risk of oral cancer. The Oral Health Foundation reports that 1 in 3 oral cancer cases is linked to excessive alcohol consumption^[18]. Using both tobacco and alcohol increases the risk even further^[3].
• Human papillomavirus (HPV): Infection with the sexually transmitted human papillomavirus, specifically the HPV 16 type, has been linked to oral cancers^[3]. Most throat cancers are caused by the human papillomavirus^[3]. However, HPV is implicated in the back of the throat area (oropharynx) rather than the oral cavity itself^[5].
• Sun exposure: Spending a lot of time in the sun without protecting your lips with sunblock can increase risk^[2]. Cancer of the lip can be caused by sun exposure^[3].
• Age: Risk increases with age. Oral cancers most often occur in people over the age of 40^[3].
• Gender: Oral cancer affects more than twice as many men as women^[3].
• Poor nutrition: A diet low in fruits and vegetables has been linked with increased risk of oral cancer^[3].
• Family history: Having a family history of oral cancer increases risk^[2].
• Genetics: People with inherited defects in certain genes have a high risk of mouth and middle throat cancer^[3].

It is important to note that 25% of people who develop oral cancer don’t smoke or have other known risk factors^[2]. A growing rate of people, mostly women aged 40 to 60 who have no additional risk factors, are developing mouth cancer^[20].

Signs and Symptoms

Oral cancer has several signs and symptoms that may be mistaken for common problems or changes in your mouth^[2]. You may notice patches inside your mouth that you can’t scrape away. These patches may be precancerous conditions, meaning that the abnormal cells are not yet cancer, but there is a chance they may become cancer if they aren’t treated^[6].

The most common precancerous conditions of the mouth are leukoplakia and erythroplakia^[6]. These conditions all appear as patches in your mouth and throat, but they’re different colors:

• Leukoplakia: These are flat white or gray patches in your mouth or throat^[2].
• Erythroplakia: These are slightly raised or flat red patches. These patches might bleed when scraped^[2].
• Erythroleukoplakia: These patches are red and white^[2].

If you have any of the following symptoms for more than two weeks, you should see a dentist or a doctor^[3]:

• A sore, irritation, lump or thick patch in your mouth, lip, or throat^[3]
• Sores on your lip or inside your mouth that bleed easily and don’t heal within two weeks^[2]
• A white or red patch in your mouth^[3]
• Rough spots or crusty areas on your lips, gums, or inside of your mouth^[2]
• Areas in your mouth that bleed for no obvious reason^[2]
• Persistent sore throat, a feeling that something is caught in your throat, or hoarseness or loss of your voice^[3]
• A lump in the neck^[3]
• Difficulty chewing, swallowing, or speaking^[3]
• Difficulty moving your jaw or tongue^[3]
• Numbness, pain, or tenderness on your face and neck or in your mouth^[2]
• Swelling of your jaw that causes dentures to fit poorly or become uncomfortable^[3]
• Pain or bleeding in the mouth^[3]
• Numbness in your tongue or other areas of your mouth^[3]
• Ear pain^[3]

Any mouth sore that won’t heal or bleeds easily, any persistent lump or soreness in the mouth, throat, or tongue, or any difficulty chewing or swallowing warrants further investigation, which includes considering oral cancer as a cause^[15].

Diagnosis

Because oral cancer can spread quickly, early detection is important. An oral cancer examination can detect early signs of cancer. The exam is painless and takes only a few minutes^[3]. Your regular dental checkup is an excellent opportunity to have the examination^[3].

Tests that examine the mouth and throat are used to diagnose and stage lip and oral cavity cancer^[14]. During the examination, your healthcare provider will look for signs of cancer in your mouth and may perform several tests:

• Physical examination: Your healthcare provider will look inside your mouth for signs of cancer, such as white patches or sores^[2].
• Biopsy: If your healthcare provider finds something suspicious, they may take a small sample of tissue (a biopsy) to check for cancer cells. Any red or white lesion persisting longer than two weeks warrants referral for biopsy^[15].
• Imaging tests: Tests such as X-rays, CT scans, MRI scans, or PET scans may be used to determine whether cancer has spread to other parts of your body^[2].

Oral cancer is curable if detected at an early stage^[1]. You should know that this disease isn’t always visible in its early stages, which is why comprehensive oral cancer screenings are recommended to all patients^[18].

Treatment Options

The treatment you’ll have for mouth cancer depends on the size of the cancer, where the cancer is, if it has spread to other parts of your body, if the cancer has certain genetic changes, and your age and general health^[13]. You may be offered a combination of treatments including surgery, chemotherapy, radiotherapy, and targeted medicines and immunotherapy^[13].

Oral cancer is usually treated with surgery first. Surgery may be followed with radiation therapy or sometimes radiation therapy and chemotherapy^[12]. Reconstruction may be needed to repair structures in the mouth and jaw or to help with speech and swallowing^[12].

Surgery

Surgery is the most well established mode of initial definitive treatment for a majority of oral cancers^[16]. Surgery is usually needed to remove mouth cancer. You may also need to have some of the lymph glands in your neck removed^[13]. Sometimes an area around the cancer may also need to be removed to stop the cancer coming back. This may include part of your tongue or jaw^[13].

If a large part of your jaw or tongue is removed, you may need surgery to rebuild the area using skin or bone from another part of your body, called reconstructive surgery^[13]. The radial forearm free flap provides excellent soft tissue and lining for soft tissue defects in the oral cavity. The fibula free flap remains the choice for mandibular reconstruction^[16].

Radiotherapy

Radiotherapy uses radiation to kill cancer cells. Radiotherapy is often used to treat mouth cancer. It may be the only treatment you need if your cancer is found early^[13]. You may also have radiotherapy after surgery or if you’re unable to have surgery^[13].

Chemotherapy

Chemotherapy is medicine that kills cancer cells. It is sometimes given with radiotherapy for mouth cancer^[13]. You may have chemotherapy for mouth cancer before or after surgery, if your mouth cancer has come back, or if cancer has spread to other parts of your body^[13].

Targeted Medicines and Immunotherapy

Targeted medicines kill cancer cells. Immunotherapy is where medicines are used to help your immune system kill cancer cells. Targeted medicines or immunotherapy are sometimes used to treat mouth cancer that has spread to other parts of the body or has come back after treatment^[13].

Treatment of oral cancer is guided by clinical staging and may involve surgical resection, lymph node dissection, radiation therapy, or chemotherapy^[15]. Long-term follow-up is advised because of the potential for recurrence or development of additional lesions^[15].

Prognosis and Survival

Approximately 63% of people with oral cavity cancer are alive five years after diagnosis^[2]. The five-year survival rate is 67% if the cancer spreads locally and 40% if it spreads to distant parts of the body^[20].

Survival rates have improved over the last 20 years and if cancer is caught early it can be cured. With the right care, cancer patients can have a good quality of life^[22]. Most of the cancers will come back within the first two years of treatment. And if somebody gets to five years after treatment with no sign of cancer, the chance of it coming back is very, very low^[8].

Over the course of the past thirty years there has been improvement in the overall survival of patients with oral carcinoma largely due to the improved understanding of the biology of local progression, early identification and treatment of metastatic lymph nodes in the neck, and employment of adjuvant postoperative radiotherapy and chemoradiotherapy^[16].

Prevention

To help prevent cancers of the oral cavity and pharynx, limit alcohol and do not use tobacco^[5]. Several steps may help prevent oral cancer:

• Quit tobacco: If you use tobacco, quitting can dramatically reduce your risk and improve oral and overall health^[18]. The most important thing is not to use any tobacco^[8].
• Limit alcohol consumption: The American Cancer Society recommends no more than 2 drinks a day for men and 1 drink a day for women^[18]. It is also important not to drink too much alcohol or to abstain from alcohol altogether^[8].
• Maintain good oral hygiene: Consistent brushing, flossing, and dental cleaning do not just protect against cavities and gum disease. They also help in identifying warning signs of oral cancer early^[18]. A person’s risk for oral cancer goes up 2.5 times if they have periodontal disease, and 60 times higher if they have 6 or more missing teeth^[18].
• Eat a healthy diet: Increase fruit and vegetable consumption. A diet low in fruits and vegetables has been linked with increased risk of oral cancer^[3]. Eating a diverse, plant-based diet rich in antioxidants and fiber is a smart way to reduce your risk of cancer naturally^[18].
• Protect yourself from sun exposure: Use sunblock on your lips to reduce the risk of lip cancer^[2].
• Consider HPV vaccination: Speak to your doctor about HPV vaccination, which can prevent new infections of certain types of HPV that can cause oropharyngeal cancers^[5]. Emerging evidence suggests that vaccination against HPV can help prevent oral cancers^[15].
• Regular dental visits: Visit your doctor and dentist regularly. Cancers detected at earlier stages have better survival rates^[5]. Maintain regular oral visits, ideally twice a year^[18].
• Reduce stress and exercise: It is very important to try and reduce stress and to exercise on a regular basis^[8].

Raising awareness about oral cancer can lead to earlier diagnosis, improved survival rates, and better quality of life. When communities adopt preventive habits and understand the risks, they take proactive steps to protect themselves and others^[19].

Living with Oral Cancer

It can be very difficult coping with a diagnosis of mouth cancer, both practically and emotionally. At first, you are likely to feel very upset, frightened and confused. You may also feel that things are out of your control^[22]. It is very important to get the right information and support to help you along the process.

The recovery period can be a difficult time for some mouth cancer patients. After treatment, patients may have problems with breathing, swallowing, drinking and eating. Speech may also be affected, and occasionally even lost. Facial disfigurement can also occur^[22]. This can lead to other problems such as nutritional deficiency, and depression.

Difficulties in communication, low self-esteem, social isolation and the impact on relationships can cause as much distress as the cancer itself^[22]. Rehabilitation is therefore a very important part of the treatment. The healthcare team will make sure that a patient is able to access services that may include reconstructive or plastic surgery, speech therapy, dietary counselling, and emotional support^[22].

Physical Changes After Treatment

Radiotherapy can affect your taste buds and can cause a dry mouth, called xerostomia. It may last for several months, but some people may find that the dryness is permanent, which may make eating and talking uncomfortable^[22]. Mouth cancer treatment can leave your throat and jaw feeling very sore and you will almost certainly have difficulty swallowing and chewing for a while^[22].

Surgery that involves the jaw, tongue, mouth, lips and throat may change the way you look. But modern surgical techniques and reconstructive surgery are usually very good. They tend not to cause much scarring, even with very big operations^[22]. How you look is an important part of how you feel about yourself. It can be very hard to accept sudden changes in your looks that you are not happy with^[22].

Emotional Support

Mental illness after or during a diagnosis of oral cancer is very common. The most common things that patients experience are depression and anxiety. Depression is very common, particularly when patients are going through treatment or immediately afterwards where they still have a lot of symptoms that they’re trying to recover from^[8].

Talking to your friends and relatives about your cancer can help and support you. It is natural to worry about these things. But it is important to remember that the people close to you will not think of you any differently as a person. They will want to support you as much as they can, so let them know how you are feeling^[22].

Patients who have had mouth cancer must be closely monitored to make sure that the cancer does not return^[22]. Specialist nurses can help if you’re finding it difficult to cope or if you have any problems. They can get you the help you need^[24].