Historically, most of the patients are above 40 years of age at the time of discovery of oral cancer. Aging is an important factor because the immunity diminishes with age as well as there are increased chances for the cells turning from benign to malignant tumor cells. This is further supported by the fact released recently in 2008 which says that oral cancer exists even among the non smokers who are below 50 years of age.
Predominantly the cause for oral cancer is attributed to the factors like the use of tobacco, consumption of alcohol and infection by Human Papilloma Virus (HPV). Among all these different causes, tobacco is considered to be the primary culprit although it takes a long time to get precipitated into an oral cancer. Especially the people who are above 50 years of age are widely affected and more than 75% of those people are constant users of tobacco. Tobacco in combination with alcohol is even more harmful and the chances are 15 times more for oral cancer if a person is addictive to both tobacco and alcohol. Recent reports also suggest that the demographics are changing rapidly as the incidence of oral cancer caused by viral infections is increasing day by day.
The factors for the cause of oral cancer can be grouped as physical factors, chemical factors and biological factors. Alcohol and tobacco comes under chemical factors. Ultraviolet (UV) rays and x-rays are the major physical factors responsible for causing oral cancer. UV rays cause lip or skin cancers. Radiographs in x-rays can cause various types of neck or head cancers. Now days, there is more awareness towards physical factors and the percentage of people getting affected by this has drastically reduced over the past few decades.
Biological factors indicate the fungi and the viruses which has a major link towards causing oral cancer. Human Papilloma Virus16 which spreads through sexual transmission causes oral cancers in tonsils, base of tongue, oropharnyx and tonsillar crypt. About 40 million people from America are found to be infected by this virus. There are nearly 120 strains of Human papilloma virus. Among them HPV16 is found to be more harmful and a potential cancer causing agent. HPV16 also causes cervical cancer, cancer in penis and anus. This virus is suspected to spread even more in the near future because of the increase in sexual intercourse among younger generation in the last 10 to 15 years.
There are also other minor factors which can cause oral cancer like lichen planus (a disease that causes inflammation of tissues in the oral cavity), improper diet with less vegetables and fruits etc. The risk for oral cancer due to these factors is very marginal and it is less likely that it contributes to the development of cancer.
Different types of oral cancer
Oral tumors can develop in different areas of the mouth and throat viz., oral cavity, oropharynx (which means the back of the mouth where it has a connection with the throat) etc. The tumors can be either Benign (non-cancerous) or cancerous. Sometimes it can also be precancerous (a condition where it may become cancerous).
What are benign tumors?
Benign (non-cancerous) tumors are of many forms and can appear in the oral cavity, oropharynx or other sites in/on the body. They are as follows:
condyloma acuminatum (also called as genital warts)-a small, moist, red or pink growth which grows alone or in cauliflower-like clusters.
eosinophilic granuloma- a benign tumor that often affects both children and adolescents. It is commonly found in the lungs or a bone.
fibroma-a benign tumor which consists of fibrous connective tissues.
keratoacanthoma-a fast-growing, flesh-colored bump on the skin which has a keratin plug in the center (keratin is a tough substance and is the main component on the external layer of skin, nails and hair).
leiomyoma-a tumor of the smooth muscle. It is normally found in the small intestine, esophagus, uterus, or stomach.
lipoma-a tumor that is made up of mature fat cells
neurofibroma-a fibrous tumor which consists of the nerve tissue.
odontogenic tumors- tumors in the jaw
osteochondroma-a tumor that is made up of cartilage and bone.
papilloma- a tumor that resembles like a wart, which grows on the epithelium (the cells that actually forms the skin and mucous membranes)
pyogenic granuloma-a round, small bump which often has an ulcerated surface.
rhabdomyoma-a striated-muscle tumor which usually appears on the pharynx, tongue, uterus, heart or vagina.
Schwannoma-a single tumor which grows in the neurilemma (Schwann’s sheath) of nerves.
verruca form xanthoma- wart-shaped tumors
The behavior of the benign tumors is quite unpredictable as some of them do not recur, some needs to be removed surgically and some of them disappear on their own. It is always better to consult a physician for diagnosis.
What oral conditions may be precancerous?
There are 2 conditions in the mouth which can actually be the precursors to Oral cancer.
•Leukoplakia – characterized by a white colored patch that develops inside the throat or mouth.
•Erythroplakia – characterized by a red colored raised patch which develops inside the mouth.
This is often caused by smoking or chewing tobacco. Biopsy is used to determine whether precancerous cells (dysplasia) or cancer cells exists in any of the above 2 conditions. This can be treated by the use of retinoids – (medications that are related to vitamin A) – to reduce, eliminate and/or prevent dysplasia from forming.
What are malignant oral tumors?
Among the several types of malignant oral cancers, most of them are squamous cell carcinoma.
squamous cell carcinoma-Also called as squamous cell cancer, that originates in the squamous cell layer in the lining of the oral cavity and/or oropharynx. In the initial stages, this cancer is present only in the lining layer of cells (called carcinoma in situ). During spreading beyond the lining, it is called as invasive squamous cell cancer.
Verrucous carcinoma-Though it is considered as a type of squamous cell carcinoma, Verrucous carcinoma rarely spreads to distant sites or metastasizes. This low-grade cancer comprises less than 5 percent of all diagnosed oral cancers. But it can spread into the surrounding tissues deeply, which may result in the surgical removal of a wide margin of the tissue.
minor salivary gland cancers-The lining of the oropharynx and oral cavity contains numerous salivary glands. Cancer may also originate from the salivary gland although it is rare. Treatment for this type of cancer depends on the type, location and the extent of spreading.
Oral Cancer: Prevention and Detection
It is a fact that the oral cancer patients are subject to less impairment or deformity when the cancer is diagnosed at a very early stage. The preventive measures can be classified into two namely
1.Primary prevention: Reduction of exposure to alcohol, tobacco and betel quid. This lowers the occurrence of oral cancer to a greater extent.
2.Secondary prevention: Screening for early diagnosis of oral cancer. The screening may be of any form. Biopsy and clinical examination helps in early diagnosis of oral cancer either premalignant or early.
Screening serves its best when the high-risk sites like floor of the mouth, soft palate, ventrolateral surface of the tongue, etc are inspected. Owing to the high cost of screening the entire population, initially the high-risk groups, especially people over the age of 40, alcoholics and smokers. It is essential for all people to have a visual oral cancer check-up every year and get a report stating that no suspicious oral lesions are found.
OraTest along with toluidine blue is mostly used as an accessory while examining soft tissue in order to emphasize asymptomatic lesions if any present. Exfoliative cytology helps in detection of early oral cancer. This rapid, non-invasive procedure can easily be conducted by an inexperienced dental personnel. Hence it is very helpful in screening programs involving the entire populations.
Oral CDx brush biopsy technique is recently found to be very efficient in diagnosing cancerous as well as precancerous lesions. To keep a control on the development of secondary tumors, frequent examinations of not only the patient but also the family members of the patient are highly recommended owing to the risk exposure.
Irrespective of the screening method used, a biopsy is essential to confirm a negative result. It is necessary for the people to be aware of the importance of a regular dental check-up for the early detection of any warning signs and to understand the risks of consumption of alcohol and tobacco. Tumor suppressor gene mutations and oncogene can be better indicators. It is to be understood that any disease can be treated in a better manner in case it is detected early.
There are some steps suggested to be followed while examining mouth.
•Pay attention to any white or red patches in the mouth, lumps or thickened skin or tissue or gums, unhealed sore (does not heal for more than 2 weeks), bleeding sore, etc.
•Observe if there is a sore throat, hoarseness persistently or if you find it difficult to maneuver jaw while swallowing or chewing.
•Consult your dentist immediately in case you find something odd about the following
oRemoval of any dental products
oObserving and feeling the parts like lips, gums, etc
oTest the roof of the mouth, inside of cheeks, back gums, tongue, etc
oPresence of enlarged lymph nodes under jaw or in neck portion.
Monthly dental checkups enable early detection and helps in prevention of oral cancer.
Treatment of Oral Cancer
Fear and frustrations often builds its phantoms which are sometimes more fearsome than reality itself. This holds true for cancer patients too. It is often unavoidable to feel stressed, frustrated or shocked when a person is diagnosed with cancer. But a patient has to keep his/her calm and should be ready to ask the doctor any of questions he/she has and get it clarified. It is better to take notes or record the voice of the doctor when the queries are answered. This can be kept for reference so that the patient understands about the disease and the treatment. It is often recommended that the patient meets the doctor along with a friend or a family member to take notes or discuss and more importantly for moral support.
A patient can approach for specialists in Chemotherapy, radiation therapy and surgery like otolaryngologists (special doctors for nose, throat and ear), radiation oncologists, oral surgeons and plastic surgeons. There are also professionals who work on health care like speech pathologist, mental health counselor, dentist and nutritionist.
Getting a Second Opinion
Sometimes the patient may opt for second opinion or even the doctor may suggest for it. There are a lot of ways in which a patient can find specialists/doctors for getting the second opinion. They are as follows:
•Most often the doctor knows about the specialists for a particular disease. The doctor might refer the patient to those specialists.
•The patient can contact Cancer Information Service to get information on the treatment centers that can be reached soon.
•Hospitals, medical colleges or schools and other health information centers can provide information on the specialists in the located area.
•The NCI website provides valuable information on finding specialists or doctors and the corresponding treatment centers and hospitals.
•The American Board of Medical Specialties (ABMS) maintains a directory which has an exhaustive list of medical specialists. Almost all the public libraries have this directory. The information is also available in the website of ABMS.
•The website of ADA or American Dental Association has enough information the dentists who are specialized for treatment of oral cancer and the location of their corresponding medical centers.
Getting Prepared for Treatment
The type of treatment chosen for a patient generally depends on many factors like the tumor size, the origin of development of cancer cells, the extent to which the cancer has spread and the general health of the patient. It is important for the patient to discuss the treatment with the doctor and get clarified on impact of treatment to normal activities like talking, swallowing etc. A patient may have an number of questions before treatment. Therefore the doctor must have a discussion with the patient based on his/her personal needs and values.
1.Medicinenet.Inc. 2009. Oral Cancer. Available at http://www.medicinenet.com/oral_cancer/article.htm (Retrieved Jan 10, 2010)
2.Oral Cancer Foundation. 2009. Oral Cancer Facts. Available at http://www.oralcancerfoundation.org/facts/ (Retrieved Jan 12, 2010)