Cancer can be a very daunting experience. It can also be laden with jargon. To help, here’s a glossary of some of the terms associated with mouth cancer.

If you can’t find what you’re looking for here, please contact our Dental Helpline on 01788 539780 (local rate number) to talk to someone who can help. Our Dental Helpline offers completely free advice and information from our oral health experts.




Abscesses and blisters

Swellings that contain pus or fluid from the tissues


Abnormal conditions


Refers collectively to the complex throat (pharynx), lungs, and oesophagus


Without symptoms and without pain



Mild, slowly progressing, or non-threatening characteristic of an illness or non-malignant character of a tumour (growth)


The surgical removal of a small piece of tissue taken from the body. These specimens are usually sent to a pathologist for histological examination.

Buccal mucosa

The lining of the inside of the cheeks. Includes the openings of numerous minor salivary glands and the openings of the major salivary glands.

Back Top



Cancer of epithelial tissues classified by type and degree.

Chemical keratosis

Chemical keratosis may also occur as a result of the compounds in smokeless tobacco, certain toothpastes, acid medication used inappropriately (aspirin placed on the gingival to alleviate toothache pain), and certain chewing gums especially cinnamon and peppermint.

Back Top



Dysplasia is a term used to describe the appearance of abnormal cells.  These are classified as mild, moderate or severe.  It is an abnormality of development in pathology, alteration in size, shape and organisation of adult cells.  While dysplasia itself does not cause health problems, it is considered to be a precancerous condition.  Left untreated, dysplasia sometimes progresses to an early form of cancer known as carcinoma in situ, and eventually to invasive cancer.

Dorsum of the tongue

The top of the tongue. What you see when you open the mouth. Location of the taste buds.

Back Top



Outermost or surface layer of the skin and mucous membranes.


Erythro-leukoplakia is when erythroplakia and leukoplakia are adjacent or admixed.  The red areas of erythroleukoplakic lesions are the sites most likely to contain or to develop dysplastic cells and should, therefore, be the sites most readily biopsied and most carefully examined clinically.  The clinician must also be thorough in his or her clinical examination of adjoining mucosa because erythroplakia and erythroleukoplakia are seen adjacent to or part of 33 % and 60 %, respectively, of all early squamous cell carcinomas of the mouth.  While it has been shown that oral carcinomas with associated or adjacent leukoplakia behave in a less aggressive fashion than carcinomas without such lesions, no similar data are available relative to carcinomas associated with erthroplakia.


Erythroplakia is an abnormal chronic red, velvety mucosal patch which cannot be given another specific diagnostic name and cannot be attributed to traumatic, vascular or inflammatory causes, i.e. it is a diagnosis of exclusion.  Once a biopsy is performed the term may still be used but should be modified to include the presence or absence of atypical or dysplastic epithelial cells.


This is a growth of cells which form red coloured patches.


Spitting or coughing up.

Back Top



The microscopic examination of the tissue sample taken from a biopsy specimen for evaluation of disease.

Hyperkeratosis frictional

It is a common alteration, especially in areas of recurring, mild mechanical trauma or irritation from mal-positioned teeth, dental prosthetics or patient habit, such as smokeless tobacco use, exuberant toothbrushing with an overly firm brush (toothbrush keratosis), constant rubbing of the tongue against the teeth (tongue thrust keratosis), or the frequent clenching of the facial muscles, thereby pushing cheek and lips firmly against dentition (chronic cheek bite keratosis, chronic lip bit keratosis).  In most cases the cause is obvious, but without a known etiology the clinician is forced to presume the keratotic plaque to be leukoplakia and to manage it as a premalignancy.

Back Top



Someone, whose immune system is damaged, subdued or overstressed. Does not allow the immune system to fight off disease.


The incidence of a disease is the rate at which new cases occur in a population during a specified period.

In vivo

Living state.

Back Top



This is a white haze or white patches sometimes interspersed with red patches as a result of heavy smoking, particularly in relation to pipe and cigar smoking.

Back Top



Voice box, structure located in the throat where air passing through it produces the sound of speech.


A wound or injury. A distinct abnormal change in the tissues. E.g. an abscess or an ulcer.


Leukoedema is a common developmental alteration of the oral mucosa which appears to be a simple variation of normal anatomy. When the mildest cases are included, it is seen in almost 90% of adult blacks and half of adult whites, although it presents as a much less pronounced alteration in whites.


Leukoplakia is a chronic white mucosal patch which cannot be scraped off, cannot be given another specific diagnostic name. Leukoplakia demonstrates a thickened surface layer of parakeratin, sometimes orthokeratin.  Leukoplakia usually doesn’t cause permanent damage to tissues in the mouth. Typically, the patient is older than 45 years of age and is male. There is a strong association with tobacco use and perhaps with alcohol abuse.

Lichen Planus

Lichen Planus is a common inflammatory disease of the skin and mouth or both. It affects about one or two percent of the general population. It is not an infectious disease. It is impossible to catch Lichen Planus from someone or to give it to someone else. The disease is not a form of cancer, it does not appear to be inherited and it is not related to nutrition. Oral Lichen Planus affects women twice as often as men. Lichen Planus occurs most frequently in middle-aged adults. The cause of Lichen Planus is not known but most dermatologists believe it can be classified as an autoimmune disease.


Malignant tumour of the lymph nodes

Lymph nodes

Glands that are located in various parts of the body that act as storage spaces for lymph fluids and white blood cells. They become enlarged in the presence of infection, toxic substances and abnormal cells.

Back Top



A harmful constituent or form of disease that is difficult to treat and usually is life threatening.

Malignant transformation rate/potential

Malignant transformation rate/potential is the risk of cancer being present in a precancerous lesion or condition, either at the time of initial diagnosis or at a future date. The potential for mucosa without precancerous lesions or conditions is termed “normal”.


To spread disease from the primary site to other parts of the body. Usually refers to a cancer.


Refers to a small cellular structure containing DNA. Mitochondria have a double membrane the inner of which contains the components of the electron transport chain. Responsible for energy production and cellular respiration.


Skin cells division.


A diseased state. The ratio of sick people to well people in a population.


Shape and size of an object. Usually used to describe the characteristics of tissue cells observed in a specimen.


The incidence of death from a disease.

Back Top



New growth.

Nicotine stomatitis

Nicotine stomatitis is found in males older than 45 years of age with long-term tobacco use. The palatal mucosa becomes diffusely grey and then white, with scattered white papules with punctuate red centres, representing inflamed salivary glands and ducts.  In severe cases the palate becomes fissured and takes on the appearance of a dried lake bed.

Back Top



Passage tube for food extending from the base at back of throat to the opening to the stomach.

Oral cavity

Encompasses the structure from the lips to the opening of the pharynx (throat), includes teeth, gum, palate and floor of the mouth.

Back Top



A doctor who specializes in the study of the causes and nature of disease.


Refers to the throat. The junction of the back of the mouth, the windpipe and oesophagus.

Potentially malignant lesions

It is not uncommon to find a variety of abnormalities in the mucous membranes lining the oral cavity. The vast majorities of these abnormalities are not malignant, and are not very likely to be so. However, some of these conditions may be considered as indicators of possible future malignancy and they are therefore known as pre-malignant lesions. By definition, these lesions demonstrate dysplasia (i.e. abnormal cell structures) on histological examination.

Pre-malignant lesions include Dysplasia, Erythroplasia, Keratosis, Lichen Planus and Submucous Fibrosis.

Precancerous lesion

Precancerous lesion is an apparently benign, morphologically altered tissue which has a greater than normal risk of containing a microscopic focus of cancer at biopsy or of transforming into a malignancy after diagnosis. It is especially important to remember that a premalignancy is not guaranteed to transform into cancer, as was once the common belief. Many, in fact, do so only in a small proportion of cases, forcing the clinician to make some very real choices relative to the management of such lesions.


The prevalence of a disease is the proportion of the population that are cases at a point in time.

Back Top



Outcomes or consequences of disease.

Squamous Cell Carcinomas

Squamous cell carcinomas are cancers of the epithelial cells. Almost 90 per cent of oral cancers are squamous cell carcinomas. Basement membrane is involved. It is a malignant tumour of squamous epithelium that shows squamous cell differentiation.

Submucous fibrosis

This is a condition found in the Asian population who chew paan (betel nut) and other tobacco preparations, which are highly corrosive and irritant to the tissues in the long term.


Displaying the symptoms of a disease


A simultaneous interaction between two factors producing an enhanced result that could not have been achieved by either factor on its own.

Back Top



A wound or an injury caused by an agent. In dentistry usually refers to an injury from a prothesis or appliance.

Abrasion: from eating some hard food like toast.

Thermal burns: heat from heat retaining foods like melted cheese.

Chemical burns: from highly irritant substances like strong mints, aspirin which are kept in mouth for prolonged periods of time.

Ill-fitting prostheses: dentures, orthodontic appliances etc.


Increased growth of cells of the body. A tumour is also referred to as neoplasm, which means literally a new growth of cells.

Tumours come in many forms and may affect any tissue of the body. It is therefore possible to have a tumour of the skin, bone, muscle, nerve tissue, blood vessels, or any other structure of the body.

Tumour types:

BENIGN – those tumours which are localised and are not highly destructive. They consist of an excess of NORMAL cells.

MALIGNANT – these tumours invade the surrounding tissues, develop secondary tumours (known as metastases) and are highly destructive. They consist of ABNORMAL cells. Malignant tumours are often called Cancers. Cancers are made up of a whole range of malignant tumours, which are broadly divided into two groups:

SARCOMAS – which are derived from muscle, bone and other tissues.

CARCINOMAS – which are derived from skin and mucous membranes.

SQUAMOUS CELL CARCINOMAS – most common form of Oral Cancer. Squamous meaning scale-like or disc-shaped in appearance. This is the shape of the cells in the outer layer of skin and mucous membrane.

Back Top



The underside (ventro) and side (lateral) border of the tongue.

Vermilion border

The junction of the skin and the outer border of the lips (labial mucosa)

Back Top