Diseases of the head and neck

Question 1

What accounts for 90-94% of malignant tumours of the oral cavity?

Answer 1

Squamous cell carcinoma

Question 2

What accounts for 90-94% of malignant tumours of the oral cavity?

Answer 2

Squamous cell carcinoma

Question 3

Which parts of the oral cavity represent the highest frequency of SCC?

Answer 3

Floor of mouth

Ventrolateral tongue

Retromolar region

Lower lip

Soft palate

Gingiva

Question 4

What is the aetiology of carcinoma of the oral cavity?

Answer 4

The dominant risk factors are tobacco use and alcohol abuse

• Strongly synergistic
• Account for 75% of the disease burden of oral and oropharyngeal malignancies
• Oral smokeless tobacco is a major cause in the Indian subcontinent, parts of South-East Asia, China and Taiwan
• May be consumed in betel quids containing areca nut and calcium hydroxide

Question 5

Which virus is a risk factor for carcinoma of the oral cavity?

Answer 5

Human papillomavirus (HPV) infection

• High oncogenic genotypes such as HPV16 and 18 are also found in a variable but small proportion of oral and up to 50% oropharyngeal squamous cell carcinomas particularly involving the tonsils and tongue base
• Speculation that HPV infection arising from oral/genital contact might be important
• Interestingly these patients have a better overall survival than HPV negative patients

Question 6

What dietary factors are involved in carcinoma of the oral cavity?

Answer 6

Fruits and vegetables (high in vitamins A and C) are described as protective against oral neoplasia, related to inherent anti-oxidant properties

Meat and red chilli powder are thought to be risk factors

Question 7

What genetic factors are involved in carcinoma of the oral cavity?

Answer 7

Increasing epidemiologic evidence that a family history of head and neck cancer may be a risk factor for the disease and it is postulated that inherited genomic instability may increase susceptibility

Question 8

What precancerous lesions may be present in the oral cavity?

Answer 8

Submucous fibrosis

Actinic keratosis

Lichen planus

Leukoplakia and erythroplakia

Chronic hyperplastic candidosis

Question 9

What worsens the prognosis in carcinoma of the oral cavity?

Answer 9

Lymphovascular invasion

Question 10

What is usually the mechanism of spread from the oral cavity?

Answer 10

Tumour embolism

Question 11

Where are metastases from carcinoma of the oral cavity commonly found?

Answer 11

Local metastases = cervical lymph nodes

Distant = mediastinal lymph nodes, lung, liver, bone

Question 12

What is the most common carcinoma of the larynx?

Answer 12

Squamous cell carcinoma most common

The age-adjusted incidence is 3.6 per 100,000

Question 13

What is the aetiology of carcinoma of the of the larynx?

Answer 13

Tobacco and alcohol are recognized as the major risk factors

Infection with human papillomavirus (6 and 11)

Diets low in green leafy vegetables and rich in salt preserved meats and dietary fats

Metal/plastic workers

Exposure to paint, diesel and gasoline fumes, asbestos

Exposure to radiation

Laryngopharyngeal reflux

Genetic susceptibility

Question 14

What is lichen planus?

Answer 14

Muco-cutaneous condition

Unknown pathogenesis however suggested to be a T cell–mediated autoimmune response

Cutaneous lesions = itchy, purple, papules forming plaques with Wickham’s striae

Oral lesions = reticular striations, plaque-like, erosive, ulcerative lesions, desquamatve gingivitis

Small risk of malignant transformation

Question 15

What are vocal cord nodules and polyps?

Answer 15

Reactive lesions

Most often seen in heavy smokers or in individuals who impose great strain on their vocal cords (singers’ nodules)

Adults and predominantly men affected

Most commonly associated with a voice change e.g. hoarseness, change in voice quality, and increased effort in producing the voice

Usually located on the true vocal cords

Question 16

What are nasal polyps?

Answer 16

Recurrent attacks of rhinitis can eventually lead to focal protrusions of the mucosa

May reach 4cm in size

When large -/+ multiple can encroach the airway and impede sinus drainage

Features point to an allergic aetiology, but most patients with nasal polyps are not atopic

Question 17

What is the histology of nasal polyps?

Answer 17

Oedematous mucosa with loose stroma containing hyperplastic/cystic mucous glands and infiltrated with mixed inflammatory infiltrate rich in eosinophils

Question 18

What is sinusitis?

Answer 18

Acute sinusitis usually proceeded by acute or chronic rhinitis

Maxillary sinusitis can arise from the extension of a periapical infection from an upper tooth through the antral floor

• Oral flora
• Inflammatory reaction is non specific

Acute sinusitis may progress into chronic, especially when there is impairment of sinus drainage

• As a result of the inflammatory oedema of the mucosa
• May impound the suppurative exudate producing empyema of the sinus

Obstruction most often affects the frontal and anterior ethmoid sinuses

Question 19

What are the causitive organisms in acute sinusitis?

Answer 19

Mixed microbial flora usually inhabitants of the oral cavity, severe forms may be caused by fungi e.g. mucomycosis esp in diabetics

Question 20

What are the complications of acute sinusitis?

Answer 20

Potential of spread into the orbit or into the enclosing bone producing cranial osteomylitis, meningitis or cerebral abscess – very rare!

Question 21

Who usually gets otitis media?

Answer 21

Occurs mostly in infants and children

Question 22

What is often the aetiology of otitis media?

Answer 22

Often viral and associated with generalised upper respiratory tract symptoms

Question 23

What are the usual causative bacterial agents in acute otitis media?

Answer 23

Streptococcus pneumoniae

H. influenzae

Moraxella catarrhalis

Question 24

What does chronic otitis externa usually result from?

Answer 24

Recurrent +/- persistent episodes and failure of resolution of acute bacterial infections

Question 25

What are the usual causitive agents in chronic otitis externa?

Answer 25

Pseudomonas aeruginosa,

Staphylococcus aureus

Fungal

Question 26

What are the potential complications of otitis externa?

Answer 26

Perforation of eardrum

Aural polyps, cholesteatoma

Mastoiditis, temporal cerebritis or abscess

Destructive necrotising otitis consequence of otitis media in a diabetic person especially when P. aeruginosa is the causative organism

Question 27

What is cholesteatoma?

Answer 27

Cystic lesions lined by keratinising squamous epithelium and filled with debris and cholesterol clefts

Precipitates surrounding inflammatory reaction which is enhanced if the cyst ruptures and may result in a foreign body giant cell reaction

Associated with chronic otitis media

Question 28

What is the pathogenesis of cholesteatoma?

Answer 28

Chronic inflammation and perforation of the eardrum with ingrowth of the squamous epithelium or alternatively metaplasia of the secretory epithelial lining of the middle ear are responsible

Question 29

What are the potential complications of choleseatoma?

Answer 29

Progressive enlargement may lead to erosion of ossicles, the labyrinth (dizziness) and adjacent bone or the surrounding soft tissue

Hearing loss

Very rarely CNS complications: brain abscess and meningitis

Question 30

What is otosclerosis?

Answer 30

Abnormal bone deposition in the middle ear

Usually bilateral

Usually begins in early decades of life, most cases are familial

Question 31

What is the pathogenesis of otosclerosis?

Answer 31

Uncoupling of normal bone resorption and bone formation

Initially fibrous ankylosis -> bony overgrowth -> anchorage of middle ear bones to oval window

Degree of immobilisation governs the severity of hearing loss

Question 32

What is labyrithitis?

Answer 32

Inflammatory disorder of the inner ear or labyrinth

Produces disturbances of balance and hearing

Bacteria or viruses can cause acute inflammation of the labyrinth in conjunction with either local or systemic infections

Autoimmune processes e.g. Wegener granulomatosis or polyarteritis nodosa

Question 33

What is the aetiology of external ear carcinomas?

Answer 33

Basal cell and squamous cell carcinomas, tend to occur in elderly men and are associated with actinic radiation

Question 34

What is the aetiology of ear canal carcinomas?

Answer 34

Squamous cell carcinoma, middle-aged to elderly women, not associated with sun exposure

Question 35

What are paragliomas?

Answer 35

Most common tumour of the middle ear, originating in the paraganglia
Presenting symptoms - pulsatiletinnitus, hearing loss, aural pressure/fullness,dizziness, otalgia, and bloody otorrhea