What is oral cancer?
Cancer occurring in the tissues of oral cavity (begins at the lips and extends backwards to the front part of the tonsils) or oropharynx (part of the throat) is termed as oral cancer.
What is oral cavity?
Different parts in your oral cavity are:
- Gums and Teeth
- Lining of cheeks
- Salivary glands
- Floor of the mouth
- Roof of the mouth (hard palate)
Burden of the disease
India has one third of oral cancer cases in the world .
Oral cancer accounts for around 30% of all cancers in India .
Oral cancers in India estimated (Globocan, 2018) :
New cases: 1,19,992
In general, more men suffer and die from oral cancer than women .
Are you at risk?
- Tobacco & betel nut/areca nut (supari) consumption
- All forms of tobacco, including cigarettes, beedi, pipes, cigars, and chewing (smokeless) tobacco[6,7].
- Keeping tobacco quid inside mouth
- Paan with betel nut/areca nut (supari) are also causal agents .
- Alcohol consumption: Alcohol increases the risk of oral cancer . The risk is about twice as high in people who have 3 to 4 alcoholic drinks per day compared to those who don’t drink alcohol [10,11].
The risk of oral cancer is even higher in people who use both alcohol and tobacco .
- Sharp teeth or ill fitting dentures: Chronic irritation of gums and cheek by ill fitting dentures or sharp teeth .
- Diet : An association between diet and oral cancer has long been suggested. A well-established and quantifiable protective effect of a diet rich in fruits and vegetables has been shown in several studies. [iarc: https://screening.iarc.fr/atlasoral_list.php?cat=B2&lang=1]
- Human Papillomavirus (HPV): HPV infection increases the risk of certain types of oral cancer, especially in younger people [15,16].
- Weak immune system: People with weakened immunity are more prone to suffer from oral cancers. Certain immune deficiency diseases at birth, radiotherapy and chemotherapy, medicines given to organ transplant recipients and the Acquired immunodeficiency syndrome (AIDS) may be responsible for weakened immune system [17,18].
- Exposure to sun’s ultra violet rays: May cause lip cancer .
The following oral disorders have a risk of converting into oral cancer
Literally means “a white patch”. This is one of the most commonly found tobacco-related oral lesions. It may be present as uniformly white and flat patches with shallow surface cracks (homogeneous leukoplakia), or as mixed, red and white lesions, or with finger-like projections (non-homogeneous).
A fiery red patch that cannot be characterized clinically or pathologically as any other definable disease.10 This is a relatively uncommon lesion but with the highest risk of tranforming into cancer.
- Oral Submucous Fibrosis (OSMF) :
This condition occurs most commonly due to areca/betel nut (supari) consumption. The hallmark of this condition is fibrosis of the oral tissues resulting in a blanched, marble-like appearance, reduced mouth opening, reduced size and functionality of the tongue, sunken cheeks and so on.
- Oral Lichen Planus (OLP) :
OLP is an autoimmune disorder (a disease in which the body’s immune system attacks its own healthy cells). It most commonly presents as fine white lines or striae (Wickham’s striae), in a network or annular pattern, also an important diagnostic feature.
- Oral lichenoid lesion (OLL) :
OLLs share the clinical features of OLP as discussed above. However, these lesions are usually present on one side and develop close to the causative agent.
As the name suggests, this lesion is seen on the palate of smokers. An initial redness is followed by greyish white mucosa, along with multiple red dots (representing openings of the minor salivary glands).
How can it be prevented?
- Avoid tobacco in all forms. Also, avoid areca nut and betel nut with paan consumption.
- No alcohol intake.
- Eat plenty of fruits and vegetables.
- In case of even the slightest abnormality (red/white/mixed patch, persistent ulcer, growth etc.) in the oral tissues, consult your dentist immediately!
When should you consult a doctor? 
- A persistent sore in the mouth or face which does not heal
- Difficulty or decrease in opening the mouth
- Development of white, red or mixed patches on tongue, gums or inner linings of mouth
- A lump or hard mass in the neck
- Chronic pain in mouth, tongue/jaw pain
- Difficulty in chewing or swallowing
- Swelling, thickening, lumps or bumps on lips, gums or inner cavity of mouth
- Unexplained bleeding in mouth
- Hoarseness or change in voice
- Loose teeth and ill-fitting dentures
- Unexplained weight loss
If the above signs/ symptoms persist for more than 2 weeks, one should consult a doctor for further evaluation.
Are there test for early detection?
Many cancers of the oral cavity have a long early pre-cancer period which provide during which they may have same symptoms. Early detection of these lesions is possible during routine general health check-ups/screening by doctors/dentists/health workers (oral visual examination) or by oral self-examination.
Oral visual Examination
You can examine your mouth yourself by looking at your mouth with the help of mirror in bright light, for early detection of oral cancers.
The Standard 8 Steps of Oral Cancer Screening
- Wash your hands thoroughly
- Explore your mouth with your finger
- Tilt your head back; examine the roof of your mouth for any abnormal thickening.
- Pull the cheeks on one side at a time, inspect the inner surface and back of the gums.
- Pull out your tongue and hold it with finger upwards, inspect and feel the floor of the mouth and look carefully at the tongue.
- Feel on both sides of the neck for any lump or enlarged lymph nodes.
- If you detect any abnormality, bring it to the notice of your doctor for further evaluation.
- Medical history, General physical examination and Oral examination
A thorough history is taken before the examination regarding duration and frequency of tobacco use in any form like cigarette, beedi, chewing pan, gutka, khaini etc and of alcohol consumption.
Oral examination: A careful examination of entire inner cavity of the mouth which includes the roof of mouth, back of the throat, and inside of cheeks and lips is then carried out. The doctor looks for red or white patches or any other abnormal areas over head, neck or face. He/she also examines for any lumps, swelling or any other problem with the nerves of mouth or face. If any abnormal area is found during examination, it is confirmed by further tests which are detailed below.
- Invasive tests:
- Brush cytology: In this test, the suspected area/lesion is brushed and the cells are looked at under microscope for abnormal cells by a pathologist.
- Fine Needle Aspiration Cytology (FNAC): FNAC is generally used to diagnose metastatic carcinoma of head and neck, in the cervical region. In this test, a thin needle which is attached to a syringe is used to draw few cells from the suspected lump or swelling. These cells are smeared onto a glass slide, then stained and examined under microscope by a pathologist to examine for abnormal cells.
- Biopsy: A small piece of tissue is taken from suspicious area using a punch biopsy instrument. Sometimes it may be done under the guidance of endoscopy, if the lesion is not easily accessible. This tissue is processed in the laboratory and examined for presence or absence of cancer.
- Imaging tests:
Imaging tests are done to confirm the diagnosis, document the extent of spread of disease, staging etc. The most common diagnostic imaging tests are X-rays, CT scan, MRI and PET scan.
- Other tests:
Human Papillomavirus (HPV) Testing: Oral cancers with HPV infection are on the rise. Doctors may test the biopsy sample for the presence of HPV infection as the possible cause.
Staging and Treatment:
Oral Cancer staging is based on following parameters:
- The size of the lesion/lump/tumor
- Whether the cancer is localized to the oral tissues only
- Whether cancer has spread to the cervical lymph nodes
- Whether the cancer has spread to other parts of the body
TNM staging system
The TNM system takes in to account.
- Tumor size (T stands for tumor)
- Lymph node involvement (N stands for node)
- Whether the cancer has metastasized (M stands for metastasis), or moved beyond the oral cavity to other parts of the body.
Potentially Malignant Disorders (preceding full-fledged cancer formation) are managed by various Medical (eg. antioxidants, topical analgesics etc.) & Surgical modalities (eg. Excision, cryosurgery, LASER etc.)
Your individual oral cancer treatment is planned based on following factors: 
- Tumour factors – primary site, size, location, proximity to bone, status of neck lymph nodes, previous treatment, and histology.
- Patient factors – patient’s age, general medical condition, tolerance of treatment, occupation of the patient, acceptance and compliance by the patient, lifestyle and other socioeconomic considerations.
- Physician factors – Expertise in various disciplines including surgery, radiotherapy, chemotherapy, rehabilitation services, dental and prosthetic support, and psycho-social support.
Treatment modalities: 
Oral Cancer, at the early stages, is managed using one or a combination of the following modalities:
Early oral cancer-
- Most early-stage oral cancers can be locally excised or treated with radiotherapy, with no or minimal functional and physical morbidity.
- Elective neck dissection to remove lymph nodes may be considered in selected cases.
- Postoperative radiotherapy is indicated in patients with positive or involved resected margins who are not candidates for re-excision.
- External beam radiotherapy (by focusing a beam of radiation from a machine to its target, the area of the body affected by cancer) and brachytherapy (uses an implant to deliver radiation to the cancer site), either alone or in combination, is an alternative to surgery for early stage oral cancers.
Locally advanced cancers-
- Surgery followed by postoperative radiotherapy is the preferred modality for patients with deep infiltrative tumors and those with bone infiltration. Postoperative concurrent chemo-radiation has been found to be superior in those with surgical margins showing cancerous changes, than radiotherapy alone.
- Primary radiotherapy, with or without chemotherapy, is a reasonable option for locally advanced tumors without bone involvement.
- Only palliative/supportive treatment is provided.
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