Manifestations of
diseases of the oral cavity
Pain-
the oral cavity- richly supplied with sensory nerve endings- pain is a
feature of all diseases, including
disorders of the teeth
Changes
of the oral mucosa- such as ulcerations, vesicular
lesions (blisters), changes in colour
Ulcers- occur in
many diseases, including infections, allergy, trauma, and neoplasns
Blisters-
infections, such as herpes virur, and immunologic diseases
Leukoplakia-
white plaques on the mucosa- in hyperkeratosis, in dysplasia
Melanin pigmentation-
Peutz-Jeghers syndrome-is rare congenital syndrome with autosomal
dominance, characterized by melanotic pigmentation of mucosal and skin
surfaces, and increased risk of carcinoma of pancreas, breast, lung and ovary,
in addition patients have multiple polyps in small intestine and colon
Addison disease
-uncommon condition characterized by melanin pigmentation of skin and mucosa
following destruction of the adrenal cortex, this results in increased stimulation
of pituitary gland, high level of ACTH and MSH
Mass lesions-
solid or cystic
Non-neoplastic
disorders of the oral mucosa
- Developmental
anomalies
- White
lesions and patches
- Infections
- Pseudotumors
Developmental anomalies
Oral mucosa is subject to the same range of developmental
anomalies such as skin, and may be involved in head and neck syndromes, but
also there are anomalies confined to the oral mucosa itself
1.
Fordyce spots- heterotopic development of sebaceous glands in oral mucosa-
produce yellow spots and nodules
2.
Peutz-Jeghers syndrome- (periorifacial lentiginosis)-
autosomal dominant condition with nearly complete penetrance, it is composed of
melanocytic macular pigmentation of the lips, oral mucosa, skin together with
intestinal polyposis, most numerous hamartomatous polyps in small intestine,
the polyps have a low malignant potential, those in colon with higher risk
-the patients are in higher risk of malignancies at other sites,
including ovary, uterus and breast
-the facial pigmentation is around lips, eyes and nose and may
disappear in adulthood
-mucosal pigmentation tends to persist to adulthood
3.
Congenital epulis- present at birth as mass
attached to the gingiva, histologically composed of large granular cells with
eosinophilic cytoplasm, covered by stratified hyperplastic squamous epithelium-
completely benign
White patches.
White
sponge naevus- is rare autosomal dominant inherited condition, may be congenital or develop later in life
mainly affects buccal mucosa, may involve lips and other oral
mucosa
family history can be
detected in all cases
histologically: there is acanthosis,
parakeratosis, and edema with hydropic degeneration of the cells in the stratum
spinosum, epithelium is not dysplastic, there is no inflammation, no relation
to tumor
Frictional
keratosis- is a common cause of intraoral white patches and may be due to sharp edges of teeth or to cheek and lip sucking,
it is a response to low grade irritation
microscopy may show acanthosis or epithelial
atrophy, thick layer of orthokeratosis and prominent granular cell layer, or
less commonly hyperparakeratosis with absent granular cell layer
there is no significant dysplasia, but sometimes inflammation of
the underlying corium, no relation to tumor development
clinically- the lesions tend to form diffuse keratotic plaques
smoking
related keratosis- smoking can result in intraoral plaque formation
histologically-atrophic or hyperkeratotic
epithelium with patchy inflammation and melanin pigment in the underlying corium-
pigmentary incontinence-release of melanin from demaged cells
there is no significant dysplasia
may be seen in reverse smokers, who hold the burning end of
cigarette inside the mouth, this one may be associated with dysplasia
acute
oral candidosis-oral infections with candida
albicans are common, it forms creamy white plaques which can be rubbed off to
leave a dry, red mucosa
histologically-loose parakeratotic plaques
infiltrated by leukocytes (intraepithelial microabscesses) with hyphae-
difficult to be seen in HE stained sections but are readily visualised by staining with PAS or silver impregnation
methods, such as Grocott
wide variety of factors predispose to infection, such as depressed
cellular immunity, and inhibition of normal oral flora by broad spectrum
antibiotics
chronic
hyperplastic candidosis (candidal leukoplakia)-Candida
albicans can be present in persistent, adherent
white plaques- solitary or multiple
microscopy- shows a parakeratotic plaque
infiltrated by leukocytes, acanthosis and inflammatory infiltrate in the
corium, epithelium has elongated rete ridges with thinning of the
suprapapillary epithelium giving a
resemblance to cutaneous psoriasis, candidal hyphae can be visualized within parakeratotic
layer
hairy
leukoplakia- patients infected with HIV frequently develop painless, white
plaques on the lateral border of the tongue and occassionally elsewhere in
the mouth
microscopy-shows irregular parakeratosis
with or without candidal hyphae,
vacuolated cell with dark pyknotic
nuclei (koilocytes) in the stratum spinosum, no inflammatory infiltrate in the
corium, Epstein-Barr capsid antigen can be detected in the epithelial cell
nuclei
similar lesions have been reported occasionally in patients
receiving immunosupressant drugs following organ transplantations
geographic tongue- relatively common idiopathic condition typically
characterized by areas with loss of papillae, mild chronic inflammation in
corium, leukocytic microabscesses in the epidermis
Infections- viral,
bacterial and fungal
infections of the oral mucosa are comparatively infrequent given
the number of microorganisms present in the mouth
Viral:
1)
herpes simplex stomatitis- caused by HSV type 1- common viral
infection- usually is subclinical
in only few per cent of infected indiviuals, there are more severe
symptoms presenting as widespread gingivostomatitis, characterized by
multiple vesicles and ulcers- in children and young adults- systemic symptoms-
like fever are present
locally severe, painful, but self-limited disease- healing occurs
within two weeks, recurrent infections may be associated with abnormalities of
cell-mediated immunity
HS virus passes up the nerve trunks and infects the ganglia in
acute phase, it remains in latent form
for long time there
Herpes
labialis-in some patients- attacks of reactivation of the infection as
painful localized vesicular and ulceral lesion -reactivation is always
precipitated by exposure to sunlight, fever, common cold, etc.
2)
herpangina -is uncommon infection of the oral
mucosa by coxsackie virus A, occurs as vesicular lesion on the palate
3)
aphtous stomatitis- common lesion characterized by
recurrent attacks of painful shallow ulcers on the oral mucosa- nonspecific
acute infiltrate
cause is unknown- no infectious agent has been identified-
self-limited lesion
4)
viral warts- viral warts of the oral mucosa
present as a lesion similar to condyloma accuminatum
histologically: features suggestive of viral
etiology such as koilocytosis, numerous mitoses, viral inclusions can be
present- detection of HPV DNA sequences
within the tissue using in situ hydridization technique assists in
diagnosis- HPV type 6, 11 and 16 will be present (human papilloma virus)
Bacterial:
1.)
Acute ulcerative gingivitis:
painful condition with ulceration of the interdental papillae
between teeth, the ulcers have irregular margins and are covered with fibrinous
exudate -etiology is unclear, and
is partly relate to poor oral hygiene -smears from ulcers show mixed population
of spirochetes, and fusiform bacteria
2.)
Actinomycosis- infection of oral mucosa by actinomyces
presents as swelling of the mucosa, the organisms are normally present in the
mouth- infection is opportunistic
3.)
Tuberculosis- infection of oral mucosa by tbc
bacili is now uncommon, presents with tuberculosis ulcers that are secondary to
pulmonary tuberculosis
4.)
Syphilis- syphilitic infection of the oral mucosa is rare in this country,
the chancre of the primary infect may occur on the lips or inside the
mouth, mucous patches and ulcers may develop in secondary stage, and tertiary
syphilis may present with gumma in the tongue or palate
Fungal:
1)
candidosis -is caused by Candida albicans,
which is present as normal commensal of the mouths of about one-half of the
population
clinical infection of the oral mucosa is an example of opportunistic
infection- occurs for example in patients with increased susceptibility (with
immunosupression, in AIDS, in newborns, in patients receiving anti-cancer
therapy or long-lasting antibiotic therapy, patients with diabetes mellitus)
morphology: edema of the epithelium,
ulcerations, Candida produces inflammation, white patches- the budding yeasts
and pseudohyphae of Candida can be identified in smears and biopsy specimens
from the lesions
Pseudotumors and
hyperplastic lesions of the oral mucosa
Epulis
-pseudotumors of gingiva -these are reactive lesions of gingiva, grossly-
polypoid masses, most common types are
Granulomatous epulis- pyogenic
granuloma -reactive
inflammatory proliferation of nonspecific granulation tissue
grossly: small, bright red nodule with
ulceration of the mucosal surface
it occurs quite commonly in pregnancy-and it resolves
spontaneously
Giant
cell epulis -distinctive
lesion of gingiva composed of multinucleated giant cells and spindle
mononuclear cells, giant cell epulides tend to be highly vascularized, there
can be considerable amounts of hemosiderin, osseous metaplasia is rather common
not true neoplasm-most likely a reactive lesion, however, the
lesion tends to recur after excision
Fibromatous
epulis -composed of fibroblasts and myofibroblasts, the lesions show
variable degree of cellularity and collagen, dystrophic calcification may
occur, osseous metaplasia is common-osteofibromatous epulis
Congenital epulis-
usually seen in newborn as a polypoid lesion in the anterior maxilla, often
protrude from the mouth as a reddish swelling, histologically - the
lesion is composed of large eosinophilic cells with granular cytoplasm- the
lesion is entirely benign
Fibrous hyperplasia –common tumor-like swelling of
oral mucosa, these lesions are considered to be a response to low grade
irritation
polypoid swellings may be sessile and pedunculated
microsopically consist of collagen bundles and moderately cellular
fibrous tissue
Papillary hyperplasia
–typically seen in hard palate, belong to spectrum of denture-related , induced
stomatitits
Generalized gingival fibrous
hyperplasia –familiar or drug induced
Hereditary gingival fibromatosis-
rare condition with AD trait, may be associated with hypertrichosis,
neurological problems, such as epilepsy
Drug-induced gingival hypertrophy- seen in about half of
patients treated with anti-epileptic drug phenytoin for long period, other drug
may roduce similar- cyclosporin
Orofacial granulomatosis
– characterized by chronic granulomatous inflammation of oral mucosa, the cause
is unknown, dg after exclusion of Crohns disease, tbc and sarcoidosis
Melkersson-Rosenthal disease-cheilitis granulomatosa,fissured
tongue, facial nerve palsy
Precancerous conditions
and tumors of the oral mucosa
The most important neoplasm of the mouth is squamous cell
carcinoma- despite the accessibility of the mouth to visual inspection, most
oral cancers are detected late and their prognosis is comparable to that of
squamous cell carcinoma of the esophagus
other malignancies and benign tumor are rare, except of squamous
cell papilloma, and salivary gland-derived tumors of the oral mucosa
Benign tumors of oral mucosa
Benign tumors in the oral cavity may arise - from squamous
epithelium, from mesenchymal tissue,
from the minor salivary glands
Squamous papilloma-
are usually small, sessile or pedunculated lesions
tehy are composed of fibrovascular core, extensions of which are
covered by acanthotic stratified squamous epithelium- no evidence of dysplasia,
but koilocytic metaplasia may be present
majority of papillomas are viral in origin-
koilocytosis is a feature of viral infections
-koilocytes- clear cell with polymorphic hyperchromatic nucleus pushed to
one side
there is no tendency for malignant change
Fibroma,
lipoma, neurofibroma- benign mesenchymal tumors
Granular
cell tumor- (myoblastoma)- is not
uncommon tumor of the skin and mucosal surfaces, they arise particularly
in the mouth, where the dorsum of the
tongue is a typical site,
histologically-striking pseudoepitheliomatous
hyperplasia of the overlying epithelium with usually incospicuous granular cell
tumor in the corium (simulates squamous
cell carcinoma), the tumor consists of large cells with abundant finely
granular cytoplasm- these cells were once thought to originate from muscle
cells, however despite the fact that they seem to fuse with muscle, they appear
to be of Schwann cell origin
Oral
pre-malignancies
There is a wide range of mucosal disorders in which squamous cell
carcinoma has been shown to develop more easily
Pre-malignant
lesions- which show histologically detactable mucosal changes
Pre-malignant
conditions- more widespread or systemic
disorders affecting oral mucosa where cancer is statistically more likely to
develop- although the site is unpredictable
pre-malignant lesions include: for example leukoplakia, palatal
changes associated with smoking, and
pre-malignant conditions- sideropenic atrophy and dysphagia caused
by iron deficiency
LEUKOPLAKIA- this is a term best defined
clinically to denote a white patch or plaque
according to this definition - heterogenous group of lesions among
which epithelial dysplasias- have pre-malignant potential
in most cases leukoplakia
represents only simple hyperkeratosis resulting from chronic irritation, in
minority of cases- there is dysplasia- persistent leukoplakia should be
biopsied
Epithelial
dysplasia- lesions characterized by disordered cell maturation and proliferation associated with
increased risk of progression to maligancy
histologically-irregular hyperplasia of cells
with basal cell morphology, rete ridges show a drop-shaped configuration, loss
of both polarity of cells and normal stratification of the epithelium, nuclear
changes, such as increased nuclear-cytoplasmic ratio, hyperchromatism and
pleomorpism, mitoses in the upper layers of epithellium, abnormal mitoses,
individual cell keratinisation often in deep layers (dyskeratosis or premature
keratinisation), and loss of celllular
cohesion
-three degrees of dysplasia can be distinguished- mild, moderate,
and severe
Malignant tumors of oral
mucosa
1)
Oral squamous cell carcinoma -accounts for
over 90% of all malignant tumors of oral cavity- more common in older men
it is important to consider the site of involvement -most commonly
it arises in the lower lip (40%),
lateral margin of the tongue (20%), floor of mouth (15%)- involvement of
the upper lip, palate, gingiva and tonsillar area is less common
etiologic factors include cigarette and pipe
smoking, alcohol, the lip is more commonly affected in white-skinned people
exposed to prolonged sun light- particularly high male predominance
grossly- the oral cancer mainly presents as an ulcer, lump,
or red or white lesion
histologically- majority of oral cancers are
well or moderatelly differentiated
squamous cell carcinomas
well-differentiated carcinoma- is composed of epithelial islands
which resemble normal stratified squamous epithelium, except that they are
invading the underlying tissues and show aberrant abnormal keratinization,
there is often a prominent keratin formation in the infiltrating islands,
usually strong host response of lymphocytes in the stroma, the tumor may be
frankly deeply invasive
poorly differentiated carcinoma- are associated with poorer
prognosis, keratin formation is minimal, malignant cells do not exhibit
distinction between basal and suprabasal population, mitoses are more frequent,
and host response is usually less conspicuous than in better differentiated
carcinomas
poorly differentiated carcinomas are sometimes difficult to be
distinguished from other malignancies, such as high grade lymphomas, malignant
melanomas and sarcomas- correct diagnosis can be helped by means of
immunohistochemistry using antibodies against epithelial markers (cytokeratin),
mesenchymal markers (vimentin, desmin, actin), and melanoma markers, etc
patterns of spread- muscle, adipose tissue and other
connective tissue tend to be invaded readily by oral cancer, salivary gland
tissue and bone provide some resistence to invasion
lymph node spread is a relatively late feature of oral cancer- the
pattern follows the main anatomical drainage pathways from the primary site-
most commonly involved is submandibular lymph node
prognosis and treatment : depends on
the stage of the disease and on the site of primary tumor
compared with favourable prognosis for lip cancer- treated by
surgery alone or combination of surgery and radiotherapy- five-year survival is
around 70%
intraoral cancer has poor prognosis- 5-year survival lower than
40%
other significant adverse factor is the size of tumor at
presentation
lymph node metastases, old age (more than 70), and poor histological
differentiation- adverse prognostic factors
2)
verrucous carcinoma- is a variant of oral squamous
cell carcinoma with predominantly exophytic growth pattern, with minimal
invasion,
microscopy- shows acanthosis with low degree
of epithelial atypia, the advancing margin of the tumor forms pushing margin
rather than the finger-like invasion of
squamous cell carcinoma
it tends to have a rather indolent course with minimal if any
capacity for metastases- very good prognosis- treatment - only surgery, radiotherapy
should be avoided
