List II - Less Common 'Know of' Conditions

Question 1

What is the most common symptom of mouth cancer?

Answer 1

• Having a sore or ulcer for more than three weeks

Question 2

What does mouth cancer include?

Answer 2

• Cancer that can develop in any part of the mouth, including the tongue, the gums, the palate (roof of mouth), under the tongue, the skin lining the mouth or the lips

Question 3

What is the most common cancer in the oral cavity?

Answer 3

• Squamous cell carcinoma accounts for 90-94% of malignant tumours of the oral cavity

Question 4

How common is oral squamous cell carcinoma?

Answer 4

• 6th most common type of cancer

* Globally represents 5% of all cancers for men and 2% of all cancers for women

Question 5

Where are tumours of the oral cavity most common?

Answer 5

Highest frequency is found in:

• Floor of the mouth
• Ventrolateral tongue
• Retro-molar region
• Lower lip
• Soft palate
• Gingiva

Question 6

What are the causes of carcinoma in the oral cavity?

Answer 6

• Tobacco
• Alcohol
  (Dominant risk factors, strongly synergistic, account for 75% of the disease burden)
• Oral smokeless tobacco is a major cause in the Indian subcontinent
• May be consumed in betel quids containing areca nut and calcium hydroxide
• HPV subtypes 16 and 18 (oncogenic) are found in a small proportion of oral and up to 50% of oropharyngeal SCC particularly involving the tonsils and tongue base (HPV positive patients have a better survival than HPV negative patients)
• Dietary factors - fruit and vegetables high in vitamin A and C are described as protective, red meat and chilli powder are thought to be risk factors
• Genetic - FH thought to be a risk factor

Question 7

What are the pre-cancerous lesions of the oral cavity?

Answer 7

• Submucous fibrosis
• Actinic keratosis
• Lichen planus
• Leukoplakia and erythroplakia
• Chronic hyperplastic candidosis

Question 8

What is thought to worsen the prognosis of carcinoma of the oral cavity?

Answer 8

• Lymphovascular invasion - mechanism of spread is almost always tumour embolism
• Local metastases = cervical lymph nodes
• Distant = mediastinal lymph nodes, lung, liver, bone

Question 9

What are the other signs of mouth cancer?

Answer 9

• White patches anywhere in the mouth (leukoplakia)
• Red patches anywhere in the mouth (erythroplakia)
• Lump on the lip or tongue, or in the mouth or throat
• Unusual bleeding or numbness in the mouth
• Loose teeth, or dentures feeling uncomfortable and not fitting properly
• Change in voice or speech problems
• Weight loss
• Lump in the neck

Question 10

What is trigeminal neuralgia?

Answer 10

• Defined as severe, episodic facial pain, in the distribution of one or more branches of the fifth (trigeminal) cranial nerve

Question 11

Which branches of the trigeminal nerve are involved in trigeminal neuralgia?

Answer 11

• Typically, the maxillary or mandibular branches are affected, either alone or in combination - involvement of the ophthalmic branch alone is uncommon
• Only 3% of cases are bilateral

Question 12

What is the cause of trigeminal neuralgia?

Answer 12

• Thought to be caused by vascular compression of the trigeminal nerve in 95% of cases, leading to central demyelination of the nerve root entry zone reinforced electrical excitability, and impairment of the nociceptive system
• Rarer causes include MS, tumours, abnormalities of the skull base and AV malformations

Question 13

What are the risk factors for the development of trigeminal neuralgia?

Answer 13

• MS
• Advancing age
• Female sex
• Family history
• Hypertension and stroke

Question 14

How common is trigeminal neuralgia?

Answer 14

• Rare 2.5-5 per 100,000 per year

Question 15

What is the prognosis of trigeminal neuralgia?

Answer 15

• Variable - attacks can occur daily for weeks or months and/or there can be months or years of remission
• 50% of people with trigeminal neuralgia experience remissions of at least 6 months duration

Question 16

What are the complications of trigeminal neuralgia?

Answer 16

• Impairment of ADL’s
• Depression/isolation
• Weight loss caused by inability to eat

Question 17

When should a diagnosis of trigeminal neuralgia be suspected?

Answer 17

• If the person has pain in the distribution of the trigeminal nerve (usually lower cheek or lower jaw) that is:
• Severe - electric shock like, sharp or shooting
• Unilateral - only bilateral in 3%
• Short lived - seconds to minutes
• Recurrent - with refractory periods between attacks
• Episodic - pain may go into remission for weeks or months before returning
• Provoking factors such as light touch to the face, eating, talking or exposure to cold air
• May also have some autonomic features such as conjunctiva injection, lacrimation, nasal congestion or rhinorrhoea, eyelid oedema, ptosis or facial swelling

Question 18

What is the management of a person with trigeminal neuralgia?

Answer 18

• Assess for red flag symptoms and signs that may suggest a serious underlying cause
• Assess the person for signs of depression
• If red flags are excluded they can be started on carbamazepine
• 100mg up to x 2 daily and titrate up in steps of 100-200 mg every two weeks until pain is relieved
• Majority of people a dosage of 200 mg three or four times per day is sufficient to prevent paroxysms of pain
• If carbamazepine is not tolerated - seek specialist advice
• Arrange follow up to assess progress
• Advise the person to follow the titration advice
• Advise on the adverse effects of carbamazepine
• Consider referring to a neurologist or specialist pain service if there is severe pain

Question 19

What are the adverse effects of carbamazepine?

Answer 19

• P450 enzyme inducer
• Dizziness and ataxia
• Drowsiness
• Headache
• Visual distubances (especially diplopia)
• Steven-Johnson syndrome
• Leucopenia and agranulocytosis
• Hyponatraemia secondary to syndrome of inappropriate ADH secretion