Pathology of ENT Flashcards
What is the normal histology of the auditory meatus and external canal?
Epidermis - stratified squamous epithelium
Contain sebaceous glands and ceruminous glands
What is the epithelium of the middle ear?
Columnar lined mucosa
Eustachian tube is respiratory epithelium
What type of cells are contained within the salivary gland?
Acinar Ductal Serous cells - contain amylase Mucinous Peripheral myoepithelial cells
What bacteria can cause otitis media?
Strep pneumoniae Haemophilus influenzae Moraxella catarrhalis Pseudomonas Staph aureus
What is a cholesteatoma?
Chronic otitis media and perforated tympanic membrane leads to abnormally situated squamous epithelium in the middle ear (normal is cuboidal or columnar glandular) causing an abundance of keratin production with associated inflammation
What is a vestibular schwannoma - also called an acoustic neuroma?
Associated with the vestibular portion of CN 8
Occurs with temporal bone at the cerebellopontine angle
What should be considered in a bilateral vestibular schwannoma in a young patient?
Neurofibromatosis type 2
What will neurofibromatosis present as?
Neurofibromas Bilateral vestibular schwannoma Multiple meningiomas Gliomas Cafe au lait spots Cataracts
What is the inheritance of neurofibromatosis type 2?
AD
Tumour suppressor gene - merlin protein on chromosome 22
What can cause a nasal polyp?
Allergy Infection Asthma Aspirin sensitivity Nickel exposure
What should be considered in a nasal polyp in a child under 5?
CF (AR CFTR gene on chromosome 7)
What mucosa should a nasal polyp be covered with?
Respiratory epithelium - squamous epithelium is a metaplastic change
What will GPA present with?
Pulmonary - SOB, wheeze, chest pain
Renal - haematuria, glomerulonephritis, hypertension
Nasal symptoms - congestion, septal perforation - saddle nose
What antibody test can be used to diagnose GPA?
cANCA
Anti-PR3
What antibody test is used for microscopic polyangiitis?
pANCA
Anti-MPO
What benign lesions commonly affect the nose?
Squamous papilloma
Schneiderian papilloma
Angiofibroma
What malignant lesions commonly affect the nose?
Squamous cell carcinoma (men, smoking and a previous schneiderian papilloma) Primary adenocarcinoma Nasopharyngeal carcinoma Neuroblastoma Lymphoma
What are the different types of schneiderian papilloma?
Inverted, exophytic or oncocytic
Inverted most common - found on the lateral wall and paranasal sinus
What increases the risk of schneiderian papilloma?
Over 50 Male HPV Smoking Organic solvents Welding
What will a schneiderian papilloma present with?
Blocked nose
Sinusitis
What does a nasopharyngeal carcinoma have an association with?
EBV
Volatile nitrosamines in food
Occupation, family history
What cancers does EBV have an association with?
Burkitt’s lymphoma
B-cell lymphoma
Hodgkin’s lymphoma
Nasopharyngeal carcinoma
How does EBV cause cancer?
Hi-jacks and mimics CD4+ T cells leading to proliferation and survival of B cells
EBV encodes a protein to activate cyclin D, promoting cell transition from G0 to G1
What can cause a laryngeal polyp?
Vocal abuse
Infection
Smoking
Hypothyroidism
What is the difference between a nodule and a polyp?
Nodule - young women, will be bilateral on middle 1/3rd to posterior 1/3rd on vocal cord
Polyps are unilateral and pedunculated
What is a contact ulcer?
Benign response to injury
Posterior vocal cord
Caused by chronic throat clearing, voice abuse, GORD or intubation
What is squamous papilloma related to?
HPV exposure - types 6 and 11
Children - aggressive disease
Adults - often solitary and possible not related to HPV 6&11
What is a paraganglioma?
Tumour arising in clusters of neuroendocrine cells dispersed throughout the body
What is a chromaffin positive paraganglioma?
Sympathetic nervous system and can secrete catecholamines
Usually adrenal medulla or paravertebral - organ of zuckerkandl (bifurcation of aorta)
What is a non-chromaffin paraganglioma?
Carotid body
Aortic body
Jugulotympanic ganglia
Ganglia nodosum of vagus with clusters around oral cavity, nose, nasopharynx, larynx and orbit
What will occur with MEN2?
Pheochromocytoma
Thyroid medullary carcinoma
Parathyroid lesion
Where can a squamous cell carcinoma arise in the H&N?
Nose Sinus Pharynx Larynx Oral cavity
What are risk factors for SCC?
Smoking and alcohol
HPV - common in oropharynx
How will HPV cause cancer?
Produces proteins E6 and E7 which disrupt p53 and RB pathways (tumour suppressors) leading to cellular mortality
What is sialolithiasis?
Stones in the salivary glands leading to pain, swelling and bacterial infections
What infections can infect the salivary glands?
Paramyxovirus - mumps causing bilateral parotitis. Associated with orchitis, pancreatitis and secondary meningitis
What are the general rules for salivary gland tumours?
Parotid most common site
Tumours in the smaller glands are likely to be malignant
If young and painfull mass = MALIGNANCY
What is a pleomorphic adenoma?
Most common tumour of the parotid gland
Usually females int he 4th-6th decade
If longstanding can transform into carcinoma ex pleomorphic adenoma
What is warthin’s tumour?
Second most common benign tumour Males over 50 Rare outwith parotid Strong assoc with smoking Bilateral and multicentric
What is the most common salivary tumour worldwide and in the uk?
Worldwide: mucoepidermoid carcinoma
UK: adenoid cystic carcinoma
Why is the survival rate of an adenoid cystic tumour so low (5 year 35%)?
Frequent perineural invasion - assoc pain or LOF
