2. •
•
•
•
•
•
•
•
•
Introduction
Definition
Nomenclature
Classification
Epidemiology
Etiology
Molecular biology
Tumor metastasis
Clinical features

3. • Cancer is the common term for all malignant tumors.
• Cancer (Latin word) : crab (Ancient Greek word)
• Presumably because, a cancer cell adheres to any part that it
seize upon in an obstinate manner like a crab.
• The study of cancer is – “Oncology’’
onco = Greek onkos, meaning bulk, mass, or tumor,
logy = study

4. • Common terminologies : cancer or tumor
• Literature terminology : neoplasia or neoplasm
• It is a disorder of cell growth, characterized by
uncontrolled, uncoordinated & undesirable cell division.
• There is no exact definition for cancer.

5. • British oncologist – Dr. Willis tried to define it as –
“A neoplasm is an abnormal
mass of tissues, the growth of
which exceeds & is
uncoordinated with that of the
normal tissues and persists in
the same excessive manner
after cessation of
Kumar V. , Abbas A.K. , Fausto N. 2007. Robbins & Corton
Pathologic Basis Of Disease.7 ed. Saunders. ISBN 10: 0721601871
stimuli, which evoked the
th

6. Condition
Tissue involved
Suffix
Benign
Mesenchymal tissue
Oma
Benign
Epithelial
tissue
Malignant
Mesenchymal tissue
Sarcoma
Malignant
Epithelial
tissue
Carcinoma
• adenoma
• Papilloma
• Cystadenoma
• Papillary cystadenoma
• polyp

7. • More than 90% of head and neck malignancies are squamous
cell carcinomas.
L. Licitra, E. Felip. Squamous cell carcinoma of the head and neck: ESMO Clinical Recommendations for
diagnosis, treatment and follow-up. Ann Oncol . 2009; 20 (4):iv121-iv122. doi: 10.1093/annonc/mdp149.
• According to Stell & Maran’s Textbook Of Head & Neck
Surgery & Oncology
CANCERS OF HEAD & NECK
Squamous cell carcinoma
Non - Squamous cell carcinoma
1. Cancer of oral cavity &
1. Cancer of thyroid
oropharynx
2. Cancer of salivary glands
2. Cancer of larynx & hypophaynx
3. Sarcomas
3. Cancer of nasopharynx
- soft tissue
4. Cancer of nasal cavity & paranasal
- hard tissue
sinuses

8. • Cancer is a leading cause of death worldwide, accounting for
7.6 million deaths (around 13% of all deaths) in 2008
•




Head and Neck Cancer: Worldwide –
640,000 cases /year
356,000 deaths per annum (55% mortality)
5% incidence of all cancers (excl. skin)
5% mortality of all cancers
GLOBOCAN 2008 (IARC) Section of Cancer Information (8/12/2013).

9. - wide variations
 France (supraglottic, oral cancers)
 Hong Kong (nasopharyngeal cancers)
 India (oral cancers)

11. Region of Contribution
cancer
Oral cavity
41- 43%
Oropharynx
3rd most common
Larynx
30 %
Hypophaynx
10%
Nasopharynx
1-2%
Nasal cavity
Rare
Paranasal
sinuses
Rare
(60-70% in
maxillary sinus)

12. 1. Tobacco
2. Alcohol
3. Dental factors
4. Occupational exposures
5. Infections
6. Nutritional factors
7. Inflammatory cause
8. Genetic factors
9. Immunologic factors
10. Endocrinal disturbances
11. Radiation

13. The areas of oral cavity which is bathed with
saliva, are most common sites to be involved.
Eg. – oropharynx, crypts of
tonsil, glossotonsillar sulcus, tongue, soft palate
& posterior pharyngeal wall.
Smoking :
• 90% cases
• Contains 30 known carcinogens : polycyclic aromatic hydrocarbons
: nitrosamines
• Alcohol adds up in pathology
Black / dark
Air cured
More carcinogenic
Blend & blond
Flute cured

14. Smokeless :
• Most common in Indian suncontinent
Bidi
khaini
Chutta
paan

15. • Synergistic action with tobacco.
• Mostly associated with cancer of - lateral border of tongue
- glossotonsillar sulci
- pharyngoepiglotic fold
7 possible mechanisms –
1.
Acts as an solvent
2.
Some contents of alcoholic beverages
3.
Metabolites like – acetaldehyde
4.
Up regulation of enzyme – cyt p450
5.
Decreased activity of DNA repair enzymes
6.
Impairment of immunity
7.
Decrease resistance to cancer

16. • Different alcoholic beverages have different carcinogenic
contentes :
- Beer – Nitrosomethylamine
- Wine – tannin
- Dark liquor – ester,
acetaldehyde
- Light liquor – ester,
acetaldehyde

17. • Sharp tooth
• Oral hygiene
• Patients with ill fitting dentures
• Alcohol containing mouth washes
(to mask the smell of tobacco/alcohol)

18. Cancer
Associated factors
Cancer of oral cavity &
oropharynx
Wood dust, chemicals, coals
Cancer of larynx &
hypophaynx
Wood dust, Ni & mustard gas and
asbestos exposure, H2so4 & HCl
exposure in battery plants
paranasal sinuses
Wood dust, textile & lather dust,
flour, formaldehyde, solvents, Ni &
Cr dust, mustard gas, radium,
isopropyl alcohol.
Cancer of salivary glands
Ni alloy dust & si
Sarcomas
Urethane, ethylene derivatives,
polycyclic hydrocarbons
Cancer of nasopharynx
Cancer of nasal cavity &

19. 30-100% verrucous carcinoma
50% cases of NPC have HPV
5% cases of H&E cancers have
HIV inhections (kaposi sarcoma)
Mostly associated with
nasopharyngeal cacinoma
42 % oral cancer & all smokers
with & without cancer,have
higher HSV antibody titre.

20. Anti-oxydants
Vit A , C, E

21. Diet low in iodine : carcinoma of thyroid gland
Carcinogenic nitrosamine in
high salted fish (NPC)

22. 1. GERD : Risk factor in 36-54 % cases of laryngeal /
pharyngeal cancer.
2. PRECANCEROUS CONDITIONS OR
LESIONS : leukoplakia, erythroplakia
OSMF – in anterior palatoglossal arch

23. • Li- Fraumeni syndrome : autosomal dominant condition
mutation of p53 gene
•
•
•
•
Fanconi’s anemia
Bloom syndrome
Ataxia
Telegiactasis
Autosomal recessive disorder
with increased chromosomal
fragility are associated with
oral cavity & pharyngeal
carcinoma.
• 4-6% of cancer of larynx & hypophaynx have history of
- plummer vinson syndrome
or
- Patterson Brown – Kelly syndrome

24. • Cancer of nasopharynx has strong predilection for interaction
between genetic & environmental factors.
•
•
•
•
Gardener syndrome
Increased incidence of thyroid cancer.
25 % cases associated with hereditary form
Multiple polyposis
Cowden disease
Multiple endocrine neoplasia (autosomal dominant)
•
•
•
•
Li- Fraumeni syndrome
Children with ratinoblastoma
Gardener syndrome
Nevoid basal cell
carcinoma syndrome
osteosarcoma
sarcoma

25. • Patient suffering from HIV infection.
• Patient on long term immunosupressive medication for organ
transplantations (risk of cancer of skin & oral cavity).
• Compromised general condition

26. • Early menarchy
• Nulliparity
Increased risk for salivary gland
carcinomas
• Older age at full term pregnancy
• Log term Oral contraceptive
Decreased risk for salivary
gland carcinomas

27. • NPC : Previous history of radiation therapy for cricoid
carcinoma or carcinoma of posterior wall of pharynx.
• Thyroid & salivary gland cancer : history of radiation
therapy, exposure to radiation fallot from nuclear power plant
or nuclear weapon in childhood .

28. • 4 stages of tumor growth
1.
2.
3.
4.
Malignant changes in 1 cell (transformation)
Growth of transformed cell
Local invasion
Distant metastasis

29. Alteration in 4 normal regulatory genes
I.
II.
III.
IV.
Growth promoting oncogenes
Growth inhibiting tumor suppressor genes
Genes that regulate apoptosis
Genes involved in DNA repair

30. • A proto-oncogene is a normal gene that can become an
oncogene due to mutations or increased expression.
• Proto-oncogenes code for proteins that help to regulate cell
growth and differentiation.
• An
oncogene
is
a gene that has the
potential
to
cause cancer. In tumor
cells, they are often
mutated or expressed at
high levels

31. • A tumor suppressor gene, or anti-oncogene, is a gene that
protects a cell from the path to cancer.
• Tumor-suppressor genes, or more precisely, the proteins for
which they code, either have a dampening or repressive effect
on the regulation of the cell cycle or promote apoptosis, and
sometimes do both.

32. • The tumor-suppressor protein p53 accumulates when DNA is damaged due
to a chain of biochemical factors.
• Part of this pathway includes alpha-interferon and betainterferon, which induce transcription of the p53 gene - p53 protein
level and enhancement of cancer cell-apoptosis.
• P53 - stopping the cell cycle at G1/interphase, to give the cell time to
repair, however it will induce apoptosis if damage is extensive and repair
efforts fail.
• Any disruption to the regulation of the p53 or interferon genes will result in
impaired apoptosis and the possible formation of tumors.

33. • Self sufficiency in growth signals
• Insensitivity to growth inhibiting signals
• Evasion of apoptosis
• Defects in DNA repair
• Limitless replicative potential
• Sustained angiogenesis
• Ability to invade & metastasize

34. Acquired / environmental
• DNA damaging agents
• chemicals
• radiations
• virus
Normal cells
Successful DNA repair
DNA damage
Failure of DNA
repair
Inherited mutations in
• gene affecting DNA
repairning
• cell growth &
apoptosis
Mutation in the genome of somatic cells
Activation of growth
promoting oncogenes
Unregulated cell
proliferation
Inactivation of tumor
supressor genes
Clonal expansion
Angiogenesis &
Escape from immunity
Additional mutations
Tumor progression
Malignant
neoplasm
Alteration in genes
regulating the apoptosis
Decreased apoptosis

35. • Pathway of metastasis
1. Haematogenous spread
2. Lymphatic spread
3. Other routes
- Trancelomic spread
- Spread through the epithelial surface
- Spread through CSF
- Implantation

38. •
Unfortunately patients are most often identified only after
development of symptoms at advanced stages of disease.
•
Discomfort is the most common symptom that leads a patient
to seek care & may be present at the time of diagnosis in up
to 85 % of cases.
•
As the high risk sites of oral carcinoma are lower lip, anterior
floor of mouth & the lateral border of tongue, the examination
of oral cavity should not be neglected.
•
Careful assessment of cervical & submandibular lymph nodes
should be done & followed by examination of oral cavity.

39. Common signs and symptoms of head and neck cancers include:
•
•
•
•
•
•
•
•
•
•
•
A chronic sore throat
Hoarseness of voice
Difficulty in swallowing
Earache
Headaches
Unusual bleeding in the mouth
A discolouration on the gums, tongue, or lining of the mouth
Nasal obstruction
Numbness of the face
Trouble when breathing or speaking
Undefined weight loss

40. 1.
Red , white or red & white lesions (flat / elevated)
2.
Change in surface texture (smooth, granular, rough, crusted)
3.
Chronic ulcer , not responding to conservative management
4.
Ulcer with irregular edge & induration of underlying soft tissues.
5.
Varying degree of pain
6.
Occasional episodes of bleeding
7.
Exophytic growth may present as a cauliflower like irregular growth / flat
8.
Submucosal growth with surrounding indurations (pain in advanced stages )
9.
Bleeding & fixity to surrounding structures

41. 10. Buccal mucosa cancers involving the infratemporal fossa may lead to
trismus (D/D OSMF)
11. Hypoglossal palsy & restriction of tongue mobility, progressive difficulty
in mastication & speech, pooling of saliva, friability & surface bleeding.
12. Trismus affects the nutritional status, functional impairment (obstruction
from large mass) – decrease tolerance to CT, RT & surgery.
13. Unexplained loosening of the involved tooth/teeth.
14. Tumor closer to midline & posterior in position in oral cavity/ orophaynx
may involve bilateral lymph nodes.

42. 15. Involved lymph nodes are –
Initially – soft, mobile, non-tender, enlarged
firm to hard in texture, usually non tender,
tender (due to inflammatory response )
Advanced stage (aggressive disease) – fixation of nodes to adjacent tissue
due to invasion of cells through the capsule
16. Fixation of primary tumor to adjacent tissue overlying bone suggests
involvement of periosteum & possible spread to bone.

44. • Clinical Examination:
– Tumours, when first seen, are almost always confined to the
head and neck with no distant metastasis
– Head and neck tumours are rarely irremovable, all structures
can be removed with the tumour in continuity and repaired
later
• The majority of cases are potentially treatable

45. • Whether to treat or not depend on:
–
–
–
–
the age
the health status of the patient
advance stage
local disease
• Full assessment will lead to one of the following
conclusions:
– Patient is potentially curable
– Primary tumour is curable but patient develop another
illness
– Patient is incurable but should be treated
– Patient is incurable and should not be treated

46. • History:
– Age:
• Patient are generally over 45 years.
• Tumours affecting younger age group are usually
sinister, defective immunological make-up
• Most tumours are of epithelial origin and they require
years of abuse by smoking and tobacco
• Tumours in younger patients, who do not smoke, is
usually very sinister
• Tumours developing in an immuno-compromised
patients do not respond to any treatment modality

47. • Complaint:
– Vary widely and is often unreliable
– Painless lump which persisted for a varying period of time
– Persistent ulceration
– Difficulty of wearing denture
– Later Symptoms:
• Pain locally or referred to the jaw or ear
• Difficulty with chewing food and swallowing
• Altered speech and respiratory difficulty
– Asymptomatic and noticed during routine dental examination

48. • Examination:
– Think in term of T Staging, delineate its border by
inspection and palpation
– Record and draw the lesion from different angles using
normal anatomical landmarks
– The status of teeth should be assessed as causative and if
radiotherapy is to considered

49. CARCINOMA OF LIP
• Age and sex:
– The sixth decade and Male : female ratio is 80:1
• 93% affect the lower lip with squamous cell carcinoma,
exophytic type
• 5% in the upper lip and commonly basal cell carcinoma,
commoner in females
–
–
–
–
Solar exposure, more radiation on the lower lip
Commoner in fair complexion
Smoker - cigarette, cigar, pipe stem
In the upper lip, SCC metastasizes earlier than lower lip

50. – Covered with non-keratinized stratified squamous epithelium which is
transparent, appear red, and contain no hair, sebaceous gland or pigments
– Crusted oozing, non-tender, indurated ulceration of <1 cm
– On the vermilion border it closely cover the orbicularis oris muscle but on
the lingual side mucous gland is present within the muscle and mucosa
– Perineural invasion through mental nerve

51. – Lymphatic drainage:
• Mucosal and cutaneous systems.
• Lower lip:
– One medial trunk which drain the inner third of the lip into the
submental group
– Two lateral trunk which drain the outer two-third into the
submandibular lymph nodes
– Anastomosis account for bilateral metastases
• Upper lip:
– Drain into the periauricular, parotid, submandibular and
submental lymph nodes

52. CARCINOMA OF LABIAL MUCOSA
• Lower labial mucosa > upper
• Tobacco pouching
• Exophytic growth , swelling, ulceration
• Unilateral or bilateral lymph nodes may be involved

53. CARCINOMA OF BUCCAL MUCOSA
Site : along or inferior to a line opposite to occlusion line
(distal to third molars)
Sign : painful lesion
Appearance
Metastasis : The submandibular lymph nodes to the lower deep
cervical chain

54. CARCINOMA OF TONGUE
• A disease of the middle age and elderly with equal
sex incidence, youngers
• 85% occurs in the lateral border of the anterior 2/3
while tip, dorsum and ventral surface are rarely
involved
• Appearance : painless indurated mass or ulcer
• The lesion may be infiltrative (small on the outside
but palpation shows deep invasion) or exophytic
and usually of the well-differentiated type

55. – Specialized keratinized epithelium with collection of
minor salivary gland and muscle fibres
– The interlacing muscle fibres form an easy pathway for
cancer spread and the constant movement of the tongue
disseminates the disease widely
• Excision should be wide with 2 cm
safe margin

56. • Lymph drainage:
– Tip of the tongue:
• To the submental lymph nodes – to the lower
deep cervical chains
– The anterior 2/3:
• the lower deep cervical chains – juguloomohyoid nodes
– The posterior 1/3:
• drain to the upper deep cervical chains
 The tip and middle part of the tongue have rich bilateral capillary network
but less in the lateral margins

57. CARCINOMA OF FLOOR OF THE MOUTH
– Anterior medial part:
• Commoner than the lateral part
• Felame > male
• Spread medially into the ventral
surface of the tongue and laterally
• Deep spread to the base of the
tongue and the hyoglossus and
genioglossus muscles
• Shows bilateral lymphatic spread to
the submandibular and the
submental nodes

58. – Lateral part:
• Spread medially to the side of the tongue
• May involve sublingual &/or submandibular
glands
• Lateral spread to the alveolar ridge where
presence or absence of the teeth govern the
outcome:
– Teeth act as a barrier against buccal
spread
– In edentulous patient, the alveolar
process has resorbed and cortex is
incomplete, tumour reaches the
cancellous spaces and the canal and
spread through the nerve.

59. Deeper spread, mylohyoid muscle act as a barrier anteriorly, posteriorly
the floor is close to the skin, appear as a palpable lump in the
submandibular area.
Lymphatic drainage – through submandibular lymph nodes to the upper
deep cervical chains
Sign & symptoms :
• Painful / painless lesion
• Restricted tongue movement
• Slurring of speech
• Excessive salivation
• loosening / exfoliation of teeth
• Root resorption

60. CARCINOMA OF GINGIVA & ALVEOLOUS
 Least associated with tobacco chewing
 The lesion is usually painless
 Looks like inflammatory or reactive lesion
(eg. Pyogenic granuloma)
 Warts around the denture flanges
– Carcinoma of the lower alveolus affects the
antero-lateral part and spread to the floor of
the mouth
– Tongue and floor of the mouth tumours
reach the lower alveolus by marginal spread
in the mucosa and submucosa overlying the
sublingual, submandibular glands and the
mylohyoid muscle. They act as barrier
against deep infiltration.

61. • Edentulous jaws, mylohyoid line is on the occlusal ridge and the
loss of the cortical bone barrier will allow tumour to spread
downward into the medullary cavity
– The inferior alveolar nerve provide a pathway for perineural spread in a
predominately proximal direction with little involvement of the bone
• Nerve looks clinical normal till late
• Spread is not continuous, multiple pathological samples is required
– Lymphatic spread to the submandibular lymph nodes

62. CARCINOMA OF PALATE
• Disease of the elderly (60 – 70 years)
• Associated with reverse smoking
• Common location for carcinoma of the minor salivary
gland
• Presented as smooth, rounded, bulging masses
• Squamous cell carcinomas present as ulcerative or
exophytic lesion
• Invade the bone at an early stage
• Involve the tonsillar pillars, soft palate, nasal
cavity, nasopharynx and the antrum
• Metastases to submandibular and upper deep
cervical chains

63. •
•
•
•
Site : soft palate & oropharyngeal mucosa
Appearance : like other lesions
Size : greater than that of other sites
Symptoms : dysphagia (most common)
: pain (dull, sharp, radiating to ear)

64. • Derived from lining epithelium
of lymphoid tissue.
• Older age & male predilection
• Initial lesion is small & difficult
to detect.
SYMPTOMS :
• Serious otitis media
• Otalgia
SIGN :
• First sign is firm to hard
(enlarged) cervical lymph nodes
• Neurological symptoms
• Obstruction of eustachian tube
• Hearing loss
• Nasal obstruction
• Pharyngeal pain

65. • The sinus is related to the orbit, nose, alveolar process, infratemporal fossa
and nasopharynx.
• It has an outlet to the nose, ethmoid sinuses and the root of the teeth
• Old age & male predilection
SYMPTOMS :
• Pain
• swelling
• Nasal obstruction
• Unilateral nasal stiffness
• Pain / paresthesia of midface
(involvement of maxillary nerve)
SIGN :
• Ulceration or mass on the hard palate

66. • The inferior orbital fissure provide a route for entry of tumours into the
orbit, the periostium offer an excellent resistant barrier to spread into the
orbit.
• The roots of the upper premolars and molars and the alveolus are in
intimate contact to the floor.
• The infratemporal fossa is the space behind the maxillary antrum and it
connects to the para-pharyngyeal space, and the sphenoid bone superiorly
with foramen spinosium and ovale with their emerging nerves.
Lymphatic drainage:
• Drain posteriorly to the retropharyngeal nodes
• Directly to the jugulo-digastric nodes
• If it cross to the nose or the cheek it will drain to submandibular lymph
nodes

68. Precancerous lesion (precancer/ premalignancy)
A benign, morphologically altered tissue that has a greater than normal risk of
malignant transformation .
Eg : leukoplakia
erythroplakia
mucosal changes associated with smoking habits
carcinoma insitu
Bowen disease
Actinic keratosis, cheilitis & elastosis

69. Malignant potential : 0.3 – 10 %
Mild / thin leukoplakia
Nodular/ speckled leukoplakia
Homogenous / thick leukoplakia
Erythroleukoplakia
Verrucous leukoplakia
Ulcerated leukoplakia

70. Homogenous & smooth Erythroplakia
Granular Erythroplakia
Erythroleokoplakia

71. Stomatitis nicotina
Snuff dipper's lesion
Cigarette smoker’s lip lesion

72. -Mostly involve skin
- but sometime also may involve mucosa
- SCC in situ is termed as – Bowen Disease

73. • A cutaneous premalignant lesion
• Gives – SAND PAPER APPEARANCE
• KERATIN HORN may present

75. Precancerous condition
It is a disease or patient’s habit that doesn’t necessarily alter the clinical
appearance of the local tissue but it is associated with a greater than normal
risk of precancerous lesion / cancer development in the tissue.
Eg : OSMF
syphilis
sideropenic dysphagia
OLP
Diskeratosis congenita
Lupus Erythmatosis

76. Malignant potential : 0.2 – 0.5 % in INDIA

77. Malignant potential : 0.4 – 12.3 %
Wickham’s
striae are
diagnostic

79. It presents a chronic multiple oral mucosal
ulcers, which occurs when there is extreme
degeneration of basal cell layer of
epithelium.
Malignant potential : 1 – 15 %

82. Staging is the process subdivision of cases of cancer into same
groups in which behavior will be similar.

83. • Over the last decade the 2 principle staging classification system of head &
neck cancer, those of AJCC & UICC have undergone a convergent
evolution & are now to all interest & purposes identical.
• Classification by anatomical extent of disease is determined clinically &
histopathologicalyl is the one that the TNM system primarily uses:
T : enlargement of & invasion by primary tumor
N : spread to regional lymph nodes
M : spread to different metastatic sites

84. 4 classifications –
1.
2.
Clinical classification / pretreatment Clinical classification (cTNM)
Pathological classification / postsurgical H/P classification (pTNM)
Gx : Grade Of Differentiation Can Not Be Assessed
G1 : Well Differentiated
G2 : Moderately Differentiated
G3 : Poorly Differentiated
G4 : Undifferentiated
3.
Retreatment classification (rTNM)
Rx : Grade Of Differentiation Can Not Be Assessed
R0 : No residual tumor is present
R1 : microscopic residual tumor
R2 : macroscopic residual tumor
4.
Autopsy classification (aTNM)
Other descriptors
i. “m” suffix (> 1 primary at single site)
ii. “y” prefix : ycTNM, ypTNM

85. T. Primary Tumor
TX. Primary tumor cannot be assessed
T0. No evidence of primary tumor
Tis. Carcinoma in situ
T1, T2, T3, T4. Increasing size and/or local extent of the primary tumor
N. Regional Lymph Nodes
NX. Regional lymph nodes cannot be assessed
N0. No regional lymph node metastasis
N1, N2, N3. Increasing involvement of regional lymph nodes
Mx : Metastasis cannot be assessed
M0 : No evidence of metastasis
M1 : Presence of metastasis

87. Classification schemes that histologically categorize precursor and related
lesions
Definition
WHO 2005
Squamous
intraepithelial
neoplasia
(SIN)
Ljubljana
classification
system
An increase in the number of cells, but
with no cellular atypia
Changes are confined to the lower third
of epithelium
Mild
dysplasia
SIN 1
Basal/parabasal
cell hyperplasia
Changes extend to the middle third of
the epithelium. Cytological changes can
be more marked
Moderate
dysplasia
SIN 2
Atypical
hyperplasia
Changes involve at least 2/3rd of the
epithelium & atypia is more marked.
Severe
Dysplasia
SIN 3
Atypical
hyperplasia
Changes involve the full thickness of
epithelium, but no invasion of basement
membrane
1.
Squamous
cell
hyperplasia
Carcinoma
in situ
SIN 4
Carcinoma in situ
Squamous cell
(simple)
hyperplasia
Barnes L, Eveson JW, Reichart PA, Sidransky D. World Health Organization classification of tumours. Pathology and
genetics. Head and neck tumours. World Health Organization; 2005.
2. Isaäc van der Waal. Potentially malignant disorders of the oral and oropharyngeal mucosa; terminology, classification and
present concepts of management. 2009; 45(4-5):317–323