L35 - NPC, Other Head and Neck Tumours

Question 1

What is the most common neoplasm in nasal cavity in paediatric population?

Answer 1

juvenile angiofibroma

Question 2

Pathologenesis of juvenile angiofibroma? Presentation and onset age?

Answer 2

vascular + fibrous lesion (thickened vessels) causing malformation of nasal erectile tissue
» Benign but can infiltrate surrounding tissue and cause extensive destruction

nasal obstruction / intermittent epistaxis

Occurs in young boys (often develops around puberty, regresses afterwards)

Question 3

Pathologenesis of inflammatory nasal polyps?

Answer 3

inflammation, allergy or mucoviscidosis (cystic fibrosis)

> > very oedematous fibrous tissue infiltrated by eosinophils and plasma cells

> > respiratory epithelium showing goblet cell hyperplasia

Question 4

What are the 2 histological features of nasal polyp?

Answer 4

2 histological features (exam):

1. Infiltrated by eosinophils, plasma cells (frequent)
2. Respiratory epithelium often shows goblet cell hyperplasia

Question 5

List 4 infections of the nose/ nasal sinuses from uncommon pathogens?

Answer 5

Tuberculosis (caseous necrosis)

Leprosy

Scleroma (granulomatous disease)

• Fungal diseases: aspergillosis and candidiasis

Question 6

Pathogenesis of scleroma?

Answer 6

chronic bacterial infection

> > Fungating polypoid mass begins in nose

> > progressively extends into nasopharynx, oropharynx, larynx

> > Presents as a granulomatous disease

Question 7

List common congenital conditions that affect the nose/ nasal sinus? What physiological defect is caused?

Answer 7

cleft palate (unilateral / bilateral) / choanal atresia / stenosis

> > connection between the nasal canals and the pharynx is blocked completely or partially by a soft tissue membrane or bony plate

Question 8

Name of a group of auto-immune conditions that affect the nose/ nasal sinuses/ upper respiratory tracts? Conditions included in this group?

Answer 8

Lethal midline granuloma

clinical syndrome = noninfective destructive lesion of the upper respiratory tract:
Wegener’s granulomatosis, conventional malignant lymphoma, and polymorphic reticulosis

Question 9

Pathogenesis of wegener’s granulomatosis? Clinical sequalae? (think renal)

Answer 9

• Necrotising giant cell granulomas*** from upper respiratory tract

> > spread to trachea and lungs

> > multinucleated giant cells, histiocytes infiltration + granulation tissue formation

Untreated = renal failure by renal arteritis, necrotizing glomerulitis or necrotizing vasculitis

Question 10

List an example of traumatic/ toxic cause of nasal neoplasm?

Answer 10

Wood dust associated adenocarcinoma

Question 11

List an example of endocrine/ environment cause of nasal neoplasm?

Answer 11

Allergic nasal polyp

Question 12

List the 3 sites of origin of nasal neoplasms.

Answer 12

• Epithelial
• Lymphoid
• Stromal

Question 13

What is the most common benign and malignant epithelial** nasal neoplasm?

Answer 13

Most common benign = papilloma

Most common malignant = squamous cell carcinoma (followed by malignant melanoma)

Question 14

Histology of nasal epithelial papilloma?

Answer 14

 Squamous or transitional

 Fungating mass: sometimes inverted, but not invasive

Question 15

Pathogenesis of malignant lymphoma of the nose?

Answer 15

Mainly affect T cell lineage:

small number of lymphoma cells intermixed with reactive cells like plasma cells, histiocytes, immunoblasts, neutrophils, eosinophils

> > form polymorphous mixture&raquo_space; polymorphic reticulosis

Question 16

What is the 1st and 2nd most common extra-nodal lymphoma?

Answer 16

1st = gastrointestinal 
2nd = malignant lymphoma of the nose

Question 17

Condition strongly associated with malignant lymphoma of the nose?

Answer 17

EBV infection

Question 18

Which type of nasal neoplasm can be easily mistaken for benign lesions?

Answer 18

Malignant lymphoma

Because of the scattered lymphoma cells, the early biopsy is easily mistaken for a benign lesion

Question 19

Most common epithelial nasopharyngeal neoplasm?

Answer 19

Nasopharyngeal carcinoma (NPC): 
= commonest epithelial tumor (exam)

Question 20

Epidemiology of NPC?

Answer 20

19/100,000

 Males affected 3-4 times more frequently than females

 Peak at age 44 (middle age)

Question 21

Define the 3 aetiological risk factors of NPC (excluding smoking).

Answer 21

1) Genetic factor: HLA A2 + BW 46 combination increases relative risk by 3x; family history
2) Diet: Dimethylnitrosamines in salted fish, phorbol esters in plants, oils = mutagenic compounds

3) EBV: 2 oncogenic proteins to cause proliferation:
a) . Latent membrane protein 1 (LMP1)
b) . Bam ARightFragment1 (BARF1)

Question 22

What is the serological marker for NPC patients with EBV infection?

Answer 22

IgA component of Viral Capsid Antigen (VCA)

Question 23

Multistep pathogenesis model of NPC?

Answer 23

1. Normal nasopharyngeal epithelium
2. Reversible mild hyperplasia
3. Early premalignant lesion
4. Irreversible malignant transformation

Question 24

Anatomical location of NPC? 3 Routes of spread and structures affected?

Answer 24

Fungating mass located in the fossa of Rosenmüller/ pharyngeal recess (clinically obscure area)

1) local spread to the parapharyngeal space&raquo_space; base of skull&raquo_space; foramina into the cranium
2) Local spread to blood vessels, cranial nerves, lymphatics and muscle
3) Distal spread by lymphatics or blood&raquo_space; first to the neck nodes in the head and neck

Question 25

List and explain 4 important symptoms of NPC?

Answer 25

1. Deafness, tinnitus (due to blockage of Eustachian tube) 2. Bleeding (blood in postnasal drip): very significant in early diagnosis 3. Headache (frequently temporal), facial pains (caused by involvement of trigeminal nerve) 4. Palpable upper jugular lymph nodes at the apex of posterior triangle

Question 26

Rank the 3 categories of NPC in terms of commonality?

Answer 26

1. Undifferentiated carcinoma = most common, >95% *exam* 2. Non- keratinizing carcinoma 3. Squamous cell carcinoma = uncommon

Question 27

What does non-keratinizing carcinoma NPC resemble histologically?

Answer 27

transitional cell carcinoma

Question 28

Histological appearance of undifferentiated carcinoma NPC?

Answer 28

sheets of polygonal cells or spindle cells >50% have prominent lymphoid infiltrate >> lymphoepithelioma

Question 29

Does lymphoid infiltration into NPC mean it is malignant?

Answer 29

NO not malignant >> represent a local tissue reaction to the tumour

Question 30

Treatment modalities for NPC?

Answer 30

external radiotherapy (Undifferentiated carcinoma responds best, Squamous cell carcinoma the least favourable) Adjuvant chemotherapy

Question 31

Recurrence rate for NPC?

Answer 31

High recurrence: Commonly within first 2 years following completion of radiotherapy Shown to occur after a 10-year period **Treated NPC patient should have routine follow up to detect early relapses **

Question 32

List 2 Non-epithelial neoplasms in the nasopharynx.

Answer 32

sarcomas - seen after radiation for NPC Lymphomas - important in Hong Kong. Often T-cell and also associated with EBV

Question 33

Go through VINDICATE and outline oral cavity and tongue pathologies?

Answer 33

Inflammatory = Aphthous ulcers Neoplastic = Squamous cell carcinoma – related to smoking+++ Auto-immune = Lichen planus Traumatic/Toxic = Ulcers

Question 34

List some risk factors for squamous cell carcinoma in the oral cavity?

Answer 34

```  Smoking (tobacco = 6-fold risk)  Alcohol abuse  Poor dentition  Viral infection (HSV, HPV)  Sunlight exposure ```

Question 35

Go through VINDICATE and outline salivary gland pathologies/ neoplasms?

Answer 35

Inflammatory: a) Sialadenitis – usually due to obstruction by stone b) Mucocele (due to obstruction of minor salivary gland) *exam* Infectious: Viral -mumps Auto-immune: Sjogren’s syndrome Neoplasm: benign and malignant

Question 36

List 2 benign salivary gland neoplasms. Which gland is most commonly affected?

Answer 36

Warthin's tumour and Pleomorphic adenoma* Both commonly affect parotid gland

Question 37

List 3 malignant salivary gland neoplasms?

Answer 37

- Mucoepidermoid carcinoma - Adeonoid cystic - Lymphoepithelioma- like carcinoma

Question 38

What is the most common salivary gland tumour? Which gland most commonly affected? Histology?

Answer 38

Pleomorphic adenoma parotid gland: epithelium forming small ducts, myoepithelial cells + Stroma may be myxoid / chondroid

Question 39

Treatment for the most common slivary gland tumour?

Answer 39

Pleomorphic adenoma Local excision (if in parotid: ensure preserve facial nerve) Local recurrence possible

Question 40

Which epithelium is affected in mucoepidermoid carcinoma?

Answer 40

glandular + squamous epithelium

Question 41

Salivary glands and cell types most commonly affected in adenoid cystic (malignant salivary neoplasm).

Answer 41

 More common in minor salivary glands (less so in parotid)  Composed of a mixture of myoepithelial cells + glandular cells (form gland-like cysts)

Question 42

Histological appearance of lymphoepithelioma- like carcinoma, associated disease and sites of metastasis?

Answer 42

 Looks like NPC  Can be associated with EBV  Can metastasize to lungs, lymph nodes

Question 43

Most common cause of mass in larynx?

Answer 43

Inflammatory – vocal polyp (singers' nodule)

Question 44

Pathogenesis of vocal polyps? Histological changes?

Answer 44

mechanical injury to vocal folds due to misuse >> localised form of chronic laryngitis Histological changes: - Squamous metaplasia - Localized stromal edema - Degeneration - Well-circumscribed polypoid mass

Question 45

List viral agents that cause laryngeal infection?

Answer 45

influenza, adenovirus, chickenpox

Question 46

List bacterial agents that cause acute laryngitis?

Answer 46

beta-haemolytic streptococci, Haemophilus influenzae, Corynecbacterium diphtheria

Question 47

Most common pathogen to cause epiglottitis?

Answer 47

Haemophilus influenzae

Question 48

Name a severe and rapidly progressive bacterial infection that cause severe laryngeal edema?

Answer 48

Epiglottitis by Haemophilus influenzae

Question 49

One congenital defect of the larynx?

Answer 49

laryngeal web (= thin, translucent membrane between vocal folds near anterior commissure)

Question 50

Go through VINDICATE and outline any neoplasms/ pathologies of the larynx.

Answer 50

Inflammatory = vocal polyp Neoplasm: numerous Infectious: viral, bacterial (acute laryngitis or epiglottitis) Congenital = laryngeal web Auto-immune – bee stings causing oedema Traumatic/Toxic – burns causing oedema

Question 51

Name the commonest benign tumor in larynx?

Answer 51

Squamous papillomas of larynx

Question 52

Compare the onset and presentation of different forms of Squamous papillomas of larynx?

Answer 52

1. Juvenile: - young age - soft and usually highly mobile due to a loose or long pedicle - Multiple lesions over wide area of laryngeal mucosa 2. Adult: - Later age - Single lesion - Localized on vocal cords

Question 53

Compare the recurrence and malignant change between 2 forms of squamous papillomas of larynx?

Answer 53

Juvenile: - High recurrence rate following excision - usually disappear after puberty - May become malignant after repeated irradiations Adult: - Rarely recur after excision - Malignant change even rarer

Question 54

List all the laryngeal neoplasms? (3)

Answer 54

Squamous papilloma (most common) Carcinoma-in-situ Invasive squamous cell carcinoma

Question 55

Common location of carcinoma- in - situ in the larynx?

Answer 55

Usually occurs on true vocal folds May be multi-centric in origin

Question 56

Age, history and presentation of invasive squamous cell carcinoma in the larynx?

Answer 56

Commonest in 7th decade history of chronic laryngitis or heavy smoking hoarseness, pain, dysphagia, haemoptysis

Question 57

Define the anatomical classification of invasive squamous cell carcinoma in the larynx? Rank them by commonality.

Answer 57

classified anatomically into: - supraglottic - glottic (vocal folds, anterior and posterior commissures) - subglottic ``` Glottic = most common Supraglottic = intermediate Subglottic = rare ```

Question 58

Compare the rate of metastasis between the 3 classes of invasive SCC in the larynx? Rank them by prognosis?

Answer 58

Glottic = mostly local, confined = good prognosis Supraglottic = rapid metastasis to regional LN, lungs Subglottic = rapid metastasis to regional LN, lungs = Worst prognosis

Question 59

Morphological features of laryngeal invasive SCC?

Answer 59

May be papillary / ulcerative / infiltrative Most = well-differentiated with varying degrees of keratin formation Usually direct extension within mucosa, submucosa