Diseases of the head and neck Flashcards
What accounts for 90-94% of malignant tumours of the oral cavity?
Squamous cell carcinoma
What accounts for 90-94% of malignant tumours of the oral cavity?
Squamous cell carcinoma
Which parts of the oral cavity represent the highest frequency of SCC?
Floor of mouth
Ventrolateral tongue
Retromolar region
Lower lip
Soft palate
Gingiva
What is the aetiology of carcinoma of the oral cavity?
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
Which virus is a risk factor for carcinoma of the oral cavity?
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
What dietary factors are involved in carcinoma of the oral cavity?
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
What genetic factors are involved in carcinoma of the oral cavity?
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
What precancerous lesions may be present in the oral cavity?
Submucous fibrosis
Actinic keratosis
Lichen planus
Leukoplakia and erythroplakia
Chronic hyperplastic candidosis
What worsens the prognosis in carcinoma of the oral cavity?
Lymphovascular invasion
What is usually the mechanism of spread from the oral cavity?
Tumour embolism
Where are metastases from carcinoma of the oral cavity commonly found?
Local metastases = cervical lymph nodes
Distant = mediastinal lymph nodes, lung, liver, bone
What is the most common carcinoma of the larynx?
Squamous cell carcinoma most common
The age-adjusted incidence is 3.6 per 100,000
What is the aetiology of carcinoma of the of the larynx?
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
What is lichen planus?
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
What are vocal cord nodules and polyps?
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
What are nasal polyps?
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
What is the histology of nasal polyps?
Oedematous mucosa with loose stroma containing hyperplastic/cystic mucous glands and infiltrated with mixed inflammatory infiltrate rich in eosinophils
What is sinusitis?
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
What are the causitive organisms in acute sinusitis?
Mixed microbial flora usually inhabitants of the oral cavity, severe forms may be caused by fungi e.g. mucomycosis esp in diabetics
What are the complications of acute sinusitis?
Potential of spread into the orbit or into the enclosing bone producing cranial osteomylitis, meningitis or cerebral abscess – very rare!
Who usually gets otitis media?
Occurs mostly in infants and children
What is often the aetiology of otitis media?
Often viral and associated with generalised upper respiratory tract symptoms
What are the usual causative bacterial agents in acute otitis media?
Streptococcus pneumoniae
H. influenzae
Moraxella catarrhalis
What does chronic otitis externa usually result from?
Recurrent +/- persistent episodes and failure of resolution of acute bacterial infections
