Oral cancer, also called mouth cancer, is a cancer of the group head and neck cancers that develops from cells lining the oral cavity, especially the cells lining the inside of the lips, tongue, floor of mouth, inside of the cheeks, gums or palate.
Most cancers of the oral cavity are formed in the flat cells that line the inside of the mouth. The development of the cancer may be due to aggression or repeated assaults that lead to formation of precancerous lesions, ulcers or wounds, for example; however, the majority of oral cancers are the result of smoking.
When you smoke, you tend to keep in your mouth the puffs of smoke before expelling them out. Some toxic substances inhaled into your lungs; the others remain in the oral cavity and attack the oral mucosa. That is why a cancer of the mouth tends to occur in areas where toxic substances of tobacco concentrate: lips, inside the lips and cheeks, gums, tongue, floor of mouth, the tissue behind the wisdom teeth and the bony portion of the mouth (also called hard palate or palate.
Oral Cancer Statistics
The frequency of cancers of the oral cavity has increased greatly in recent decades in most developed countries. In 2002, approximately 274 300 new cases of oral cancer were identified worldwide; nearly 145 500 people died from the disease. In the United States alone, approximately 34 000 people were diagnosed with oral cancer in 2007.
According to the National Cancer Institute (NCI), each year in the United States, about 29,000 people learn they have cancer of the oral cavity or the oropharynx. It is estimated that 35,720 men and women (25,240 men and 10,480 women) were diagnosed with cancer of the oral cavity and pharynx in 2009; about 7,600 people died of it.
The incidence of mouth cancer varies with age. From 2002-2006, the median age at diagnosis for cancer of the oral cavity and pharynx was 62 years of age. The percentages and ages of people diagnosed were approximately:
- 6% under age 20;
- 4% between 20 and 34;
- 8% between 35 and 44;
- 9% between 45 and 54;
- 2% between 55 and 64;
- 3% between 65 and 74;
- 1% between 75 and 84;
- 8% 85+ years of age.
Oral Cancer (Mouth Cancer) Causes
Oral cancer is due to DNA mutation. That is, the cancer occurs when cells begin to proliferate abnormally following an oncogenic activation in one or a group of cells. Common factors that can cause this cellular mutation are tobacco, ultraviolet light (sunshine), nuclear radiation and certain toxic chemicals. Some oral cancers can take several years after contact with the carcinogen to develop.
However, whatever the time of its development, an oral cancer is always manifested by cancerous growth in the tissues of the mouth. The cancer may grow directly into the oral cavity or through metastasis from another tissue/organ affected by the cancer. In some cases, cancer can be an extension of a tumor located in a region near the mouth, cancer of the nasal cavity or sinuses for example.
Although all the causative factors of oral cancer are not known, the main causes are clearly identified – smoking and heavy alcohol consumption. In fact, over 75 percent of cancers of the oral cavity are diagnosed in people who drink and smoke. When these two substances are combined with other carcinogens (present in foods, liquids, steam, dust, etc.) the risk is even higher.
Oral Cancer (Mouth Cancer) Risk Factors
All risk factors for oral cancer are not known; in fact, nearly 25% of cases of oral cancer are not associated with any suspected risk factor. The following conditions can increase your chance of developing mouth cancer:
- Age– oral cancer is more frequent among people aged 50 or over.
- Gender– men are twice more affected by oral cancer than women. This difference, however, have begun to decline because of growing number of women who smoke and/or heavily consume alcohol.
- Smoking– cigarette smoke is considered as the prime factor of oral cancer; the risk is much greater when tobacco is associated with alcohol abuse.
- Alcohol– moderate alcohol consumption represents no risk; excessive alcohol use, especially in combination with smoking, is a major cause of mouth cancer.
- Prolonged exposure to sunlight– overexposing your lip to sunlight can cause formation of cancerous cells in its tissue.
- Infection– poorly or untreated human papillomavirus (HPV) infection may provoke formation of a malignancy in your mouth.
- Radiotherapy– radiation treatments in the head or neck area can damage healthy cells in your mouth and cause them to turn into cancerous.
Mouth Cancer (Oral Cancer) Symptoms
Symptoms of oral cancers vary depending on the location of the tumor. In general, symptoms develop from the mucosa of one of these sites: floor of the mouth, tongue, tonsils, palate, cheeks, gums or lips. If you have an oral cancer, you’ll experience at least one of the following symptoms:
- jaw pain or stiffness
- toothache or loose teeth
- persistent discomfort when swallowing (dysphagia)
- difficulty or pain when chewing
- sore in the mouth that does not heal;
- swollen lymph node in the neck
- bleeding in the mouth
- sore throat or chronic feeling that that something is caught in your throat
- difficulty or pain when you pull your tongue
- tingling or persistent pain in the mouth or throat
- whitish and/or reddish lesions in the mouth;
These symptoms do not necessarily mean you have oral cancer. However, if they persist, it is important that you consult your dentist or doctor. The risk of oral cancer increases with age. Therefore, if you are over 50 or if you have certain risk factors (excessive alcohol consumption and smoking), it is very important to see your doctor as quickly as possible if you experience any of oral cancer symptoms.
Oral Cancer (Mouth Cancer) Complications
Depending on the location of the cancer, it may impact your ability to speak, eat and laugh. In addition, some cancer surgery of the mouth can damage your face esthetically; which will cause psychological problems such as low self-esteem and feeling of discomfort in public.
Oral Cancer (Mouth Cancer) Diagnosis
If your doctor/dentist suspects signs and symptoms indicating a cancer in your mouth, he will do a physical exam to analyze oral cavity. During the examination, he look for red or white patches, lumps, swelling, sores or other changes in your neck, head, face and mouth which may explain the presence of a tumor.
However, to confirm the diagnosis and to determine if the cancer has spread, more explicit tests such as radiography, ultrasound, CT scan, magnetic resonance imaging (MRI) and bone scan will be performed. In addition, your doctor can recommend a biopsy to establish a decisive diagnose.
Imaging techniques – imaging techniques such as ultrasound, CT scan, magnetic resonance imaging (MRI) and bone scan allow your physician to have a clear information on the tumor – tissue affected, location and size of the tumor and the presence of metastases, if there is any. Cancer of the oral cavity can spread into the sinuses, skull and lungs. to confirm whether the tumor has reached these organs, your doctor may recommend X-rays and examinations of the head and neck. However, to accurately confirm the diagnosis, a biopsy should be performed.
Biopsy – to establish with certainty the diagnosis of the cancer, a pathologist will take tissue sample from your mouth, specifically from the area where the tumor is suspected, in order to perform a microscopic examination. If cancer cells are found, your doctor will determine how fast they multiply to recommend the most appropriate and effective treatment.
The biopsy also allows your doctor to determine the degree of malignancy of the cancer cells. In general, the lower is the degree of malignancy; the more favorable is your chance to survive. The low-grade cells reproduce slowly and usually have little tendency to invade surrounding tissues. The high-grade cells proliferate rapidly and are more likely to spread to other parts of the body to form metastases.
Oral Cancer (Mouth Cancer) Stages
Once it is confirmed that you have cancer in your mouth, your oncologist will determine its stage. This may require surgery, or removal of some lymph nodes near the tumor for laboratory analysis. Staging the tumor is a very important step; it helps your physician not only to choose appropriate treatment but also to determine the prognosis.
The stage of an oral cancer is often defined by Roman numerals: stage I, stage II, stage III and stage IV. Higher is the stage, more aggressive is the cancer. In general, aggressive cancers have poor prognosis.
- carcinoma in situ– also called stage 0,carcinoma in situ indicates the genesis of cancer cells;
- Stage I –the tumor is in your mouth, but it is no larger than 2 cm;
- Stage II –the size of the tumor can be larger than 2 cm but no larger than 4 cm;
- Stage III –the t umor is larger than 4 cm, and can have spread to nearby tissue;
- Stage IV –the tumor has spread into inferior alveolar nerve, floor of mouth, or skin of the face, chin and/or nose.
- Recurrent– the cancer has returned after treatment.
Oral Cancer (Mouth Cancer) Treatment
Treatment recommended by your oncologist depends on the type of cancer diagnosed, its stage, your age and health in general. However, whatever decision taken, your doctor will have to choose surgery, radiotherapy, or chemotherapy. These therapeutic methods can be used alone or in combination.
Surgery will be performed depending on the location of the tumor and its size. Usually, surgery is performed to treat limited oral cancers. The surgery may be partial or total removal of the tumor and some surrounding tissue.
Sometimes, removal of the vocal cords, jaw bone, or parts of the face is inevitable. Although the operation may prolong your life or even eliminate the cancer completely, it can affect your appearance, speech, and ability to swallow. In this case, you may be recommended a reconstructive plastic surgery to repair your face.
In large oral cancers, a tracheotomy may be necessary. If so, you’ll be obligated to breathe through a tube implanted in the trachea and not through your nose or mouth. A speech therapist will teach you how to talk.
Radiotherapy (radiation therapy)
Radiotherapy is the destruction of cancer cells using high-energy beams. Unlike chemotherapy, which acts on cancer cells throughout the body, radiation therapy acts locally; distant healthy tissue is not affected by the therapy. In some cases, your doctor can associated external radiation therapy with internal radiotherapy (brachytherapy) ton increase your survival chance. In the treatment of oral cancer, radiotherapy is often performed one month after surgery.
Side effects: in addition to redness of the skin, radiotherapy in the oral cavity always causes dry mouth. In case that the major salivary glands were irradiated at high doses of radiation, the dry mouth can be definitive.
Chemotherapy involves using powerful chemicals to kill cancer cells. Unlike surgery and radiation therapy, chemotherapy is a systemic treatment that affects the entire organism. The chemotherapy drugs designed to destroy cancer cells or prevent them from multiplying throughout the body. These drugs can be taken by infusion, injection or pill form.
However, chemotherapy drugs affect both cancer cells and healthy cells that divide rapidly, which often causes side effects:
- loss of hair
- And more..
Oral Cancer (Mouth Cancer) Survival Rates
Oral cancer survival rates vary depending on the location of the tumor, time of the diagnosis and the presence or absence of metastases. The prognosis of a mouth cancer at the base of the tongue is often bad.
In addition, the prognosis of oral cancer varies with age and race. According to the National Cancer Institute, the overall 5-year relative survival rate for 1999-2005 was 61.0%. Five-year relative survival rates by race and sex were:
- 4% for white men;
- 8% for white women;
- 2% for black men;
- 2% for black women.
Oral Cancer (Mouth Cancer) Prevention
Nearly 95% of cancers of the oral cavity are caused by alcohol and smoking, therefore, to prevent oral cancer, it is recommended to stop smoking and drinking alcohol. It is necessary to stop as soon as possible because alcohol-smoking intoxication may take about twenty-five to thirty years before transforming healthy cells into cancer cells.
Other methods to prevent oral cancer include:
- avoid or limit sun exposure
- consult your dentist regularly, about every six months
- consult your physician / dentist if you have lesions in your mouth
- maintain a healthy weight;
- reduce your exposure to toxic chemicals
- reduce your exposure to ultraviolet (UV) radiation
- exercise regularly
- practice safe sex
- keep your immune system healthy
- Adopt a healthy diet: a diet containing 5 to 10 servings of fruits and vegetables a day may help prevent occurrence of many cancers including oral cancer. Increase the following foods in your diet:
- a) avocados
- b) blueberries
- c) black Raspberries
- d) curcumin
- e) flax
- f) garlic
- g) papaya
- h) pomegranate juice
- i) tomatoes
- j) soy products
- k) grapefruits, oranges and other citrus fruits
- l) Cruciferous vegetables (broccoli, cauliflower, kale, Brussels sprouts, and cabbage).