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Examination of Oral Cavity
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241
Fig. 10.31: Respiratory system should be examined for
possible development of bronchopneumonia in oral
carcinoma especially of tongue.
Fig. 10.32: Orthopantomogram is a must to see
mandibular invasion in carcinoma oral cavity.
US neck to identify enlarged nodes.
CT scan: It is important in posterior lesions. It also
identifies neck nodes, retropharyngeal nodes.
Indirect laryngoscopy/posterior rhinoscopy, direct
laryngoscopy, bronchoscopy, are other often needed
methods to evaluate the patient (Figs 10.33A and B
and 10.34).
Ranula (Rana—frog, looks like belly of frog)
It is an extravasation cyst arising from sublingual gland
and mucus glands of Blandin and Nuhn in the floor
of the mouth. Occasionally it can occur in submandibular salivary gland also. Initially there is blockage
of the sublingual duct causing retention cyst; later
A
B
Figs 10.33A and B: Indirect laryngoscopy to visualise larynx
and its parts and view of larynx as seen in laryngoscope.
increased pressure causes rupture of acini leading to
extravasation cyst.
Clinical features: It presents as a bluish smooth, soft,
fluctuant, brilliantly transilluminant swelling in the
lateral aspect of the floor of the mouth (Figs 10.35A
and B). It often extends into the submandibular region
through the deeper part of the posterior margin of
mylohyoid muscle and is called as plunging ranula.
It is cross fluctuant across mylohyoid muscle. Ranula
has a delicate fibrous capsule and is lined by a layer
of macrophages. It contains clear fluid. It is nontender
and laterally placed.
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Sublingual Dermoids
They are sequestration dermoids lined by squamous
epithelium containing keratin. Types: (1) Median
sublingual dermoid: It is derived from epithelial cell
rests at the level of fusion of two mandibular arches.
It is located between two genial muscles, above the
level of mylohyoid muscle. It is a midline swelling
which is smooth, soft, cystic, nontender, nontransilluminant (Fig. 10.36). (2) Lateral sublingual
dermoid: It develops in relation to submandibular duct,
lingual nerve and stylohyoid ligament. It is derived
from first branchial arch. It forms a swelling in the
lateral aspect of the floor of the mouth.
Fig. 10.34: Posterior rhinoscopy.
A
B
Figs 10.35A and B: Ranula. It is brilliantly
transilluminating swelling.
A
Figs 10.36A and B: Sublingual dermoid. (A) Shows inside
swelling (black arrow) extending externally to submental
region (white arrow). (B) Magnified view of the inside swelling.
Mucus Retention Cyst
B
It is due to blockage of the duct of small mucus glands
located in the mucous membrane. It is common in
inner side of the lower lip or cheek. Cyst develops
at any age group. It is painless, slowly progressive,
soft, smooth, cystic often transilluminant (but difficult
to elicit). It can often rupture spontaneously or get
bitten. When its epithelial covering is healthy, it is
pale pink in colour with gray glary appearance of visible
mucus in the cyst (Figs 10.37A and B). If overlying
epithelium is damaged, it becomes white scarred and
obscure coloured. Overlying mucous membrane is free;
it isn’t adherent to underneath orbicularis oris or
buccinator. Cervical lymph nodes are not enlarged.
Leukoplakia
It is a white patch in the mucosa of the oral cavity
that cannot be characterized clinically or pathologically
Examination of Oral Cavity
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A
B
Figs 10.37A and B: Mucus retention cyst of
upper lip and cheek in two different patients.
to any other disease. It is a premalignant condition.
Types: (1) Homogenous. (2) Nodular—more
potentially malignant. (3) Speckled—much more
potentially malignant.
Clinically the lesion appears as white or grayish
coloured, well localised patch in the cheek, tongue,
palate or other areas of the oral cavity (Fig. 10.38).
Common causes: Smoking, spirit, sepsis, superficial
glossitis, syphilis, spices, sharp tooth, susceptibility,
pan chewing using areca, tobacco, slaked lime, chronic
hypertrophic candidiasis. Incidence of leucoplakia
in those who smoke or chew pan is 20%, whereas
incidence in nonsmokers is 1%. Incidence of it turning
into malignancy is 2-4%. It increases with age, duration
of the pan chewing, smoking.
Histology: Parakeratosis with widening of rete pegs.
Histological staging: Acanthosis; Parakeratosis;
Widening of rete pegs; Dyskeratosis; Dysplasia;
Carcinoma in situ.
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Fig. 10.38: Leukoplakia cheek.
Erythroplakia
It is red velvety appearance of the mucosa which cannot
characterise any recognised condition. It is 17-20
times more potentially malignant than leucoplakia.
Histologically parakeratosis with severe epithelial
dysplasia is the typical feature. It is equal in both sexes.
It is common in lower alveolar mucosa, gingivobuccal
sulcus and floor of the mouth. It can be homogenous,
speckled, and granular or erythroplakia interspersed
with leukoplakia.
Oral Submucosal Fibrosis
It is a progressive fibrosis deep to the mucosa of the
oral cavity which causes trismus and ankyloglos-
sia.The mucosa of cheek, gingivae, palate and tongue
shows a mottled/marbled pallor . It is common in Asians
and Indians.
Etiology: Hypersensitivity to chilli, betel nut, tobacco
and vitamin deficiencies (riboflavin) probably alter
the collagen metabolism leading to juxtaepithelial
fibrosis, epithelial atrophy and dysplasia. 4-7% of oral
submucosal fibrosis can turn into malignancy.
Prevalence in India is 5 per 1000. It is common in
middle age; equal in both sexes; incidence is 4-7%.
Initial red area turns into superficial ulcers which later
forms stiff fibrotic bands and scarring. It is common
in buccal mucosa, soft palate and faucial pillars. It
is progressive disease showing epithelial hypertrophy,
hyperplasia, dysplasia and fibrosis (Fig. 10.39).
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Fig. 10.39: Oral submucosal fibrosis.
Premalignant Conditions of Oral Cavity
High Risks—Lesions with Definite Risk of
Malignant Change
SRB’s Clinical Surgery
Leukoplakia; erythroplakia; chronic hyperplastic
candidiasis – It is common in commissures of the mouth
and tongue (Fig. 10.40).
without anaemia); or Plummer-Vinson syndrome.
Sideropenia is common in Scandinavian females. It
causes atrophy of epithelium and becomes potentially
malignant. Proper iron therapy controls the disease
and reduces the risk.
Equivocal Risk Lesions
Oral lichen planus, dyskeratosis congenital, discoid
lupus erythematosus.
General Features of Oral Carcinoma
Oropharyngeal cancer is the most common cancer –
40% in Indian subcontinent. In western countries it
accounts for 4% only. Risk factors—tobacco and
related products; alcohol; areca nut; human papilloma
virus; Epstein Barr virus; Paterson-Kelly syndrome;
nutritional deficiency. Patient may develop a second
primary (15%) in the oropharynx in different site at
the same time or within 6 months of the existing primary
(synchronous—4% prevalence; 20% of second
primaries) or after 6 months of first primary (metachro-
nous—80% of second primaries). Metachronous
second primary is more common than synchronous
second primary and it usually occurs in 2 years. In
India cheek is the commonest site, then tongue, floor
of the mouth, palate and lips. In western countries
tongue, floor of the mouth, lip and cheek is the order
of occurrence. Problems with oral carcinoma: Upper
airway obstruction especially posterior growths;
bronchopneumonia; feeding difficulties; malnutrition;
infection; torrential bleeding due to erosion of vessels
like lingual; fixity of secondaries; fungation; disability
and psychological discomfort (Fig. 10.41).
Fig. 10.40: Oral candidiasis—curdy white patches.
Medium Risks – Premalignant but not Associated
with Higher Incidence of Carcinoma
Oral submucosal fibrosis; syhilitic glossitis; sideropenic dysphagia (Sideropenia is iron deficiency
Carcinoma Cheek
Squamous cell carcinoma is the most common
carcinoma of the cheek. Occasionally it can be adeno-
carcinoma arising from the minor salivary glands or
mucus glands. It may be also rarely melanoma.
Precipitating Factors
All ‘S’—Smoking, Spirit, Syphilis, Sepsis, Sharp tooth,
Spices. It is common in Chutta smokers (Tobacco
enrapped in a tobacco leaf). Chutta carcinoma is
Examination of Oral Cavity
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Fig. 10.41: Carcinoma of lip, cheek and tongue. Patient
was earlier (3 years early) operated for carcinoma cheek.
Now metachronous growths appeared in lip, cheek and
tongue.
common in Andhrapradesh and Orissa. Pipe smoking
(buccal carcinoma); snuff use (floor of the mouth);
different mouth washes may be other aetiologies.
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buccinator, pterygoids; into the retromolar trigone,
base of the skull, pharynx. It spreads outwards to
involve the skin causing fungation, ulceration,
orocutaneous fistula formation (Fig. 10.42). Mandible
is commonly involved either by direct extension or
through subperiosteal lymphatic plexus which communicates freely with oral lymphatics. Lymph nodes
commonly involved are submental, submandibular,
deep cervical and often lateral pharyngeal groups.
Nodal spread is observed in 50% of cases. Infection
of the tumor area and soft tissues around is common,
causing fever, foul smelling ulcer , halitosis.Respiratory
infection is common in these patients. Once tumor
extends into the retromolar region, soft palate, pharynx,
dysphagia will occur.
Premalignant Conditions
Leucoplakia, erythroplakia, submucosal fibrosis,
hyperplastic candidiasis. Betel nut chewing (Pan, with
pan quid kept in cheek pouch for a long time) is an
important causative factor of carcinoma cheek. Types:
Ulcerative; proliferative (exophytic); verrucous.
Verrucous Carcinoma
It occurs as a superficial proliferative exophytic lesion
with minimal deep invasion. Lesion has got white,
dry, velvety or warty, keratinised surface. It is of low
grade, very well differentiated squamous cell
carcinoma, which is locally malignant without any
lymphatic spread. It is a curable malignancy. It is
common in females. It may be related to human
papillomavirus. It is often multicentric. Invasive
carcinoma also may develop in other sites.
Biological Behavior of Carcinoma Cheek
Carcinoma cheek is common in posterior half of cheek
than anterior. It spreads into the deeper plane to involve
Fig. 10.42: Carcinoma of cheek with proliferative lesion
extending to skin with sinus/possibly orocutaneous fistula.
Clinical Features
Ulcer in the cheek which gradually increases in size
in a patient with history of chewing pan, and smoking.
Pain occurs when it involves the skin, bone or if
secondarily infected. Referred pain into the ear
signifies involvement of lingual nerve. Involvement
of retromolar trigone indicates that it is an advanced
disease, as the lymphatics here communicate freely
with the pharyngeal lymphatics. Everted edge, indura-
tion are the typical features of the ulcer. Mandible
is examined bidigitally , for thickening, tenderness, and
sites of fracture. Trismus and dysphagia signifies
involvement of pterygoids, or posterior extension.
Occasionally it may extend into the upper alveolus
and to the maxilla causing swelling, pain and
tenderness. Submandibular lymph nodes and upper
deep cervical lymph nodes are involved which are
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SRB’s Clinical Surgery
Fig. 10.43: Carcinoma of cheek involving skin and soft tissues – locally advanced malignancy.
hard, nodular, and initially mobile but later get fixed
to each other and then to deeper structures. Once lymph
nodes get fixed it may infiltrate into hypoglossal nerve
(tongue will deviate towards the same side), spinal
accessory nerve (defective shrugging of shoulder) and
cervical sympathetic chain (Horner‘s syndrome).
Compression over external carotid artery causes
absence of superficial temporal artery pulsation.
Eventually it causes fungation and bleeding from major
vessels—-carotid blow out (Figs 10.43 and 10.44).
Fig. 10.44: Recurrent carcinoma cheek. Earlier patient has
undergone surgical wide excision. Note the old scar.
N2Lymph node size 3-6 cm or bilateral lymph
nodes; N2a—single node 3-6 cm size on same
side; N2b—multiple nodes 3-6 cm size on same
side; N
—bilateral or opposite nodes enlarged
2c
upto 6 cm size.
N3Lymph node size > 6cm.
Features of Advanced Carcinoma Cheek
Involvement of retromolar trigone; extension into the
base of skull and pharynx; fixed neck lymph nodes;
extension to the opposite side.
Carcinoma Lip
It is common in men; common in old age; common
in lower lip (90%) (Fig. 10.45); upper lip 5-10%;
less common in Negroes; common in white Caucasians.
It is commonly due to exposure to sunlight (ultraviolet
rays); common in pipe smokers; initially starts as a
red, granular dry lesion which eventually gets ulcerated
and forms an ulceroproliferative lesion. Occasionally
Staging (for all Oral Carcinomas)
TNM Staging.
T1Tumour size < 2cm
T2Tumour size 2-4 cm
T3Tumour >4cm
T4Tumour is of any size involving bone, soft tissues,
muscles.
N1Lymph node size <3 cm
Fig. 10.45: Carcinoma lower lip
Examination of Oral Cavity
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it occurs at the angle of mouth. Often carcinoma of
lip is an extension from carcinoma of cheek. It is slowly
progressive tumour; it spreads to submental nodes and
later to other neck nodes on both sides; usually it is
a well differentiated squamous cell carcinoma.
Causes: UV rays, smoking, cheilitis, solar keratosis,
papilloma, leukoplakia, tobacco chewing, Khaini
chewers (tobacco + lime); agriculturist who are exposed to sunlight—countryman’s lip.
Clinical features: Nonhealing progressive painless
ulcer/ulceroproliferative lesion; offensive discharge;
proliferative with everted edge; stony hard in consistency; cannot be moved separately from lip; indurated
edge and surrounding area; bleeds on touch; palpable
hard submental/submandibular/upper deep cervical
nodes.
Differential diagnosis: Keratoacanthoma, basal cell
carcinoma, minor salivary gland tumours.
Carcinoma Tongue
Incidence is equal in both sexes. Presently its incidence
is increasing in females due to increase in number
of female smokers.
Etiology: Leucoplakia, erythroplakia, all ‘S’s mentioned earlier, premalignant conditions mentioned
earlier.
Types: Gross: (1) Papillary; (2) Ulcerative or
ulceroproliferative; (3) Fissure with induration; (4)
Lobulated, indurated mass.
Histologically: Squamous cell carcinoma—com-
monest; adenocarcinoma may be from minor salivary
glands or mucus glands; melanomas. Sites: Lateral
margin—commonest–47-50% (Fig. 10.46); posterior
third—20%; dorsum—6.5%; ventral surface—9%;
tip—10%. It is common in India and France.
Clinical Features
Painless ulcer/swelling in the lateral margin (commonest site) of the tongue which becomes painful later
(Florid, painless, friable, bleeding, everted edge,
sloughing yellow gray floor, serosanguinous discharge, induration of edge and base and is extending
into surrounding area are the features). Pain in the
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Fig. 10.46: Carcinoma tongue is more common in
lateral aspect of the tongue.
tongue due to infection or ulceration or due to the
involvement of lingual nerve (pain is referred to ear);
pain on swallowing, in case of carcinoma of posterior
third of tongue; excessive salivation (It is due to
irritation of nerves of taste buds and ankyloglossia
causing difficulty in swallowing saliva); dysphagia
either due to fixed tongue or due to the involvement
of genioglossus or growth in the posterior third of
the tongue; visible ulcer in anterior two thirds of tongue
with raised everted edge, area of induration is more
extensive than visible ulcer area; ulcer may cross the
midline or extend into alveolus, floor of the mouth,
mandible; bleeds on touch; growth or ulcer in posterior
third, is usually not visible. Ankyloglossia; inability
to articulate; foetor oris (halitosis) due to infection
and necrosis in the oral cavity; change in voice occurs
in posterior third tumours. T umour in posterior third
area is more aggressive. Indirect laryngoscopy is often
needed to visualise posterior third of the tongue. Lymph
nodes may be palpable in the neck which are hard,
nodular and may get fixed in advanced stages. Features
of bronchopneumonia may be present. Spread of
carcinoma tongue: Local spread: In case of anterior
two thirds of tongue, the spread occurs to genioglossus
muscle, floor of the mouth, opposite side and mandible.
In case of posterior third of tongue it spreads locally
to tonsil, side of pharynx, soft palate, epiglottis, larynx
and cervical spine. Lymphatic spread: From tip of
tongue it spreads to submental nodes. From lateral
margin it spreads to submandibular lymph nodes and
later to upper and middle deep cervical lymph nodes.
Lymphatics in the tongue are freely communicating,
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Fig. 10.47: Lymphatic drainage of tongue.
SRB’s Clinical Surgery
and so involvement of bilateral neck lymph nodes
is common. From posterior third it spreads to
pharyngeal nodes and upper deep cervical lymph
nodes. Posterior third growths can show blood spread
(Fig. 10.47).
common. Carcinoma posterior third of the tongue is
often poorly differentiated and so carries poor prognosis. Blood spread can occur into bones, liver and
lungs in posterior third cancers. Palpation under
anaesthesia gives better idea about the tumour, its
spread and also allows the biopsy. CT scan is always
needed to plan the staging and therapy. Lymphoepithelioma and transitional cell carcinoma can occur
in posterior third tongue (rarely).
Carcinoma Floor of the Mouth
It is usually aggressive tumour. It is rare in India. It
is 2nd common site of oral carcinoma (SCC) in western
countries. It invades hyoglossus, mylohyoid, genioglossus and anterior mandible early . Trismus, ankyloglossia, mandibular spread is common. Bilateral neck
nodes are commonly involved (Fig. 10.48). Prognosis
is poor and also has poor cosmetic results.
Terminal Events in Advanced Cases
Aspiration pneumonia; erosion of major vessels by
primary tumour (lingual artery) or by secondaries in
neck (carotid artery); cachexia; laryngeal oedema;
asphyxia; starvation due to inability to swallow.
Carcinoma of Posterior One-Third /
Base of the Tongue
Here lesion may remain asymptomatic for long time.
Clinically it may be missed easily . Earlier symptoms
are features mimicking sore throat and throat
discomfort. Dysphagia and change in voice (hot potato
voice) occurs later. Referred pain in the ear , bleeding
from mouth, visible mass in posterior third of tongue
is late local features. Induration on palpation in
posterior third tongue is diagnostic of the carcinoma.
As posterior third tongue has got abundant lymphatics
which cross communicates on either side, lymph node
spread is common (70%). Bilateral nodal spread is
common. Massive nodes and involvement of jugulodigastric node are also common. Infiltration into the
tongue muscles like genioglossus, epiglottis, preepiglottic space, tonsillar pillars and hypopharynx are
Fig. 10.48: Carcinoma floor of the mouth.
Carcinoma Alveolus
It is squamous cell carcinoma arising from gums. It
is common in males. It is common in India. It is
commonly due to tobacco/pan chewing. Features and
precipitating factors are similar to other oral carcinomas. There will be invariable bone involvement by
direct extension. Nodal spread is also common.
Carcinoma of Hard Palate
Squamous cell carcinoma in the hard palate is common
in males; common in reverse smokers (Rolled tobacco
Examination of Oral Cavity
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leaf – Churat); due to repeated thermal injury . It spreads
to periosteum, bone, maxilla, sinus or nose. Ulcerated
raised everted edge with induration and fixity is the
presentation. Upper deep cervical nodal spread occurs
in 25% of patients. Hard palate is the common site
for minor salivary gland tumours (Fig. 10.49). They
are commonly malignant; common is adenoid cystic
type; single solid smooth swelling with ulcer over the
summit is the presentation. Edge biopsy, FNAC of
nodes; CT scan of neck and base of skull are the needed
investigations.
249
palpable neck nodes and referred pain are common
features. Hoarseness of voice, loss of weight,
respiratory obstruction, and halitosis are late features.
Carcinoma in epiglottis causes bilateral nodal spread.
Local spread occurs to vallecula, base of tongue and
pyriform fossa. Glottic (65%): It is the commonest
type. It begins from upper part or free edge of vocal
cords (mid or anterior) often extending 10 mm below.
Lymphatic spread is slow (only 4%) as this area has
got least lymphatics. Opposite vocal cord can involve
as kiss cancer. Vocal cord mobility is unaffected in
early cases. Vocal cord fixation signifies spread to
thyroarytenoid which is a poor prognostic sign. It
presents very early due to hoarseness of voice. Eventual
cord fixation causes stridor. Locally it spreads
anteriorly to anterior commissure, posteriorly to vocal
process and arytenoids, above to ventricle and false
vocal cords, below to subglottis. Subglottic (2%)
cancer is less common involving undersurface of true
vocal cords and subglottic space. It spreads to deep
cervical and paratracheal nodes (20%). Upward spread
is rather late and so hoarseness is not an early symptom
in this type. It can spread through cricothyroid
membrane or thyroid gland (Figs 10.50 and 10.51).
Fig. 10.49: Carcinoma of hard palate.
Laryngeal Carcinoma
Aetiology: Smoking, tobacco, alcohol intake, occupational/industrial exposure to chemicals like mustard
gas, asbestos, benzopyrones, petroleum products,
previous radiation, genetic—Russians develop familial
laryngeal cancers, papillomavirus, Herpes simplex
virus, EB virus, keratosis, malnutrition.
Incidence: Squamous cell carcinoma is commonest
(95%); common in males (10:1); common in 5th/ 6th
decade.
Types: Ulcerative; Proliferative.
Anatomical types: Supraglottic (25%): It arises from
infrahyoid part of epiglottis, ventricles, and arytenoids.
It spreads to neck lymph nodes early (40%) due to
rich lymphatics in this area. Throat pain, dysphagia,
Fig. 10.50: Anatomy of larynx showing supraglottic,
glottic and subglottic regions.
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Fig. 10.51: Laryngeal carcinoma types. Note the typical sites. Glottic is the
commonest site. Next is supraglottic. Subglottic is rare.
Note: In Indian subcontinent supraglottic tumours are
more common than glottic. Glottic type is common
in western countries. Fixation of cords is due to
involvement of thyroarytenoid muscle or cricoarytenoid joint.
Clinical features: Hoarseness of voice; pain and
discomfort; cough. dyspnoea, stridor, dysphagia in late
cases; bloody sputum; palpable neck nodes, which
eventually get fixed; absence of laryngeal crepitus.
It is common in males—10:1.
Investigations: ILS (Indirect laryngoscopy); direct
laryngoscopy and biopsy; CT neck—very useful
investigation; chest X-ray; FNAC of lymph node;
microlaryngoscopy in small lesions to identify and
to have proper biopsy; T oluidine blue staining to stain
early superficial cancers which facilitate the accurate
biopsy; Hopkin’s endoscopy; Flexible, fibreoptic
laryngoscopy.
Nasopharyngeal Carcinoma
Nasopharynx lies above the level of the soft palate
which separates it from oropharynx below. It is also
called as post-nasal space or epipharynx. Eustachian
tube opens on its anterolateral wall. Fossa of
Rosenmuller is located above and behind the opening
of the Eustachian tube as a small depression.
Clinical features: Epistaxis, nasal speech, post-nasal
discharge and nasal obstruction; pain in the ear with
unilateral deafness due to compression of Eustachian
tube with fluid collection in the middle ear; elevation
and immobility of soft palate on the same side; pain in
the area of distribution of trigeminal nerve due to direct
infiltration of the nerve at foramen lacerum; palpable
secondaries in upper deep cervical lymph nodes (70%).
Trotter’ s triad: Unilateral deafness; immobile elevated
soft palate; pain in the distribution of trigeminal nerve.
Nasopharyngeal carcinoma is common in China,
Taiwan, Hong Kong and Mongolia. It is rare in USA.
In India it is common in north east region. It is common
in males (2:1). It may be related to Epstein-Barr virus.
It is commonly squamous cell carcinoma (85%).
Lymphoma, minor salivary tumors and sarcoma are
other malignancies that can occur rarely in nasopharynx. Lymphoepithelioma of nasopharynx is called
as Schminke/Regaud tumour. Carcinoma can be of
proliferative, ulcerative, and infiltrative types.
Commonest site is fossa of Rosenmuller in lateral wall
of pharynx. It is three times common in males. HO’s
triangle in supraclavicular fossa (bounded by medial
and lateral ends of clavicle and point where neck meets
the shoulder) is the site where metastatic nodes
commonly exist in nasopharyngeal carcinoma. In 50%
of cases nodal involvement is bilateral. Often cervical
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