NasopharynxPresented by: Dr.Isha Jaiswal Moderator:Dr.Rohini Khurana Date: 11th December 2013

Nasopharynx

-Behind the nasal cavity-Extends from skull Base superiorly to the soft palate inferiorly- Communicates inferiorly with

the oropharynx through the velo-pharyngeal sphincter

- The nasopharyngeal tonsil lies in the roof

- The pharyngeal opening of ET lies in the lateral wall

ANATOMICAL EXTENT OF NASOPHARYNX

RoofFloorAnterior wallPosterior wallLateral wall

ROOF: formed by basiocciput & basispenoid.

FLOOR: Formed by soft palate anteriorly; deficient posterior called as nasopharyngeal isthmus via which it communicates with the oropharynx .

Anterior :continuous with the nasal cavity via choanae.

Posterior wall:.

Bounded by: Atlas vertebra Axis vertebraSup. Constrictor msBuccopharyngeal fasciaRetropharyngeal spacePrevertebral fascia

Lateral wall: contain openings of eustachian tube bounded by elevation called as torus tubarius.

LATERAL VIEWMEDIAL VIEW

SINUS OF MORGAGNISpace between base of

skull & sup.connstictor.Through it enters- Eustachian tube Tensor &Levator veli

palatini muscle Asc. Palatine

artery(facial artery)

a-mucosab-pharyngobasilar fasciac-muscular coatd-buccopharyngeal fascia

FOSSA OF ROSENMULLER

Fossa of rosenmuller

What is Waldeyer’s ring?

Arterial supply: External carotid artery• Ascending pharyngeal • Spheno palatine artery• Facial arteries

Venous drainage • The pterygoid venous plexus (superiorly) • The pharyngeal plexus (inferiorly)• Finally drain in int. jugular vein

Nerve supply:Sensory -Ant. to ET opening: maxillary nerve (V2) Post. to ET opening: glossopharyngeal nerve (IX)

Motor –pharyngeal plexus formed by IX,X & cranial part of XI nerve.

LYMPHATICDRAINAGELateral Retropharyngeal L.N also called as nodes of Röuviere, are the first nodes in the lymphatic drainage of Nasopharynx.Extends from base of skull to C3 cervical vertebra.

Lymphatic drainage

MUCOSA OF NASOPHARYNX

respiratory type (ciliated pseudostratified columnar with goblet cells) near the nasal cavities

non-keratinising stratified squamous type near the pharyngeal isthmus

RADIOANATOMY

Radioanatomy

TORUS TUBARIUS

ADENOIDS: nasopharyngeal tonsil

FOSSA OF ROSENMULLER

NASOPHARYNGEAL CANCER

Epidemology

NPC shows a distinct racial and geographical distribution.

The annual incidence rate (per 100,000 per year) ranged from <1 among whites to >20 among Southern Chinese populations.

Incidence common in southern China and Taiwan and they constitute high risk group. USA & rest part of world constitute low risk group.

It is uncommon in India and constitutes 0.5% of all cancers

AGE & SEX DISTRIBUTION

bimodal age distribution is observed in low risk group. First peak incidence at 15 to 25years,second peak at 50 to 59 years of age

incidence in high-risk populations rises after 30 years of age, peaks at 40 to 60 years, and declines thereafter.

Sex ratio; M:F= 2:1 to 3:1

ETIOLOGY OF NPC

GENETIC

ENVIORMENTVIRAL

GENETIC FACTORS

Chinese have higher genetic susceptibility for NPC .

Genomic studies have revealed 3 HLA locus.HLA A2; HLA B46; HLA B17 are associated with

increased risk of NPC

ENVIORMENTAL FACTOR

DIET: Chinese salted fish food contain nitrosamines: carcinogen

Lack of vit C in dietBurning of incense & woods: polyaromatic

hydrocarbon:carcinogenAlcohol consumption & Cigarette smokingoccupational exposure to dust, smoke, and

chemical fumes

VIRUSHPV associated with keratinizing type NPC???EBV associated with NON keratinizing type NPC .EBV-DNA or RNA presence in cell indicates that

the virus has entered the tumor cell before clonal expansion.

EBV’s tumerogenic potential is due to two latent genes: LATENT MEMBRANE PROTEINS (LMP)

EBV-NUCLEAR ANTIGEN (EBNA)

NASOPHARYNGEAL CARCINOMA-NATURAL HISTORY

Inception

silent period

Focal invasion

Primary lymph node station

Genetic, environmental, viral factors

Blood stained mucus, ET blockage

Locoregional spread

retropharyngeal

Systemic spread

Parapharyngeal, skull base

Clinical Manifestation

NPCsymptoms

NASAL

NEURAL

NECK MASS

EAR

SYMPTOMSOF NPC

• Neck mass: may be due to primary tumour or secondary neck nodes. Bilateral metastasis to lymph node is common

Nasal : Discharge, bleeding, obstructionAural: tinnitus, hearing lossCranial nerve palsy : Most common 6th nerveWeight loss

Clinical Manifestation

• Neck lump 60%• Ear (s) plugging & fullness 41%• Hearing loss 37%• Nasal bleeding 30% • Nasal obstruction 29%• Head pain 16% • Ear pain 14%• Neck pain 13%• Weight loss 10%• Diplopia 8%

Symptom & sign of NPC frequency at diagnostic in Mayo clinic series

Extension pathways.

Localized tumour: m.c site FOSSA OF ROSENMULLER may

present as neck mass,dysphagia.

Anterior Spread into nasal cavity

nasal symptoms

Blood-tinge anterior or posteriornasal drainage

Obstruction of nasal pathway EpistaxisHalithosisNasal congestionsinusitis

Posterior spread: into retropharyngeal lymph node.

retropharyngeal lymph node

Post.lateral spread & involvement of prevertebral muscles.

Retropharyngeal & parapharyngeal space involvement

Retropharyngeal L.N involved

Parapharyngeal spread leads to E.T blockade &

serous otitis media.

Large tumour extending into nasal cavity,parapharyngeal & prevertebral space

Superior spread: into base of skull, may involve cavernous sinus

Superior spread: infilteration of orbital cavity via inferior Orbital fissure

RETROPAROTID SYNDROME :also calledas VILLARET SYNDROME. Occur due toenlarged lateral retropharyngeal lymph nodemetastasizing to retroparotid space. Involves 9 to12 cranial nerve & cervical

sympathetic trunk. Patient presents with difficulty in speech

&swallowing, Altered taste sensations in post.1/3 of tongue. Weakness of sternocleidomastoid & trapezius muscle. Unlateral atrophy of tongue & horner’s syndrome

Ophthalmo-neurological SYMPTOMS:

PETROSPHENOID SYNDROME of JACOD: tumour invasion to base of skull may involve II

to VI cranial nerve.(II)nerve involvement lead to decreased

vision,amurosis

VI nerve involvement results in squint and diplopia. III, IV, VI nerve involvement results in

ophthalmoplegia. V nerve involvement results in facial pain & absent

corneal reflex.

Ophthalmo-neurological SYMPTOMS:

TROTTER’S TRIAD

NPC

Hearing loss

Palatal palsyFacial pain

HORNER’S SYNDROME

Inferior Spread: to oropharynx may lead to dysphagia,regurgitation

Lateral spread:otologic symptoms

• Result from eustachian tube involvement • Sensation of ear blockage • Serous otitis media• Conductive hearing loss• Tinitus

nasopharyngeal tumor with infratemporal fossa extension

LYMPHATIC SPREAD

Frequency of lymph node manifestration

• Upper jugular-94%• Middle juular-85%• Retropharyngeal

node-80%• Posterior cervical -

46%• Lower jugular-19%• Supraclavicular -17%• Submental-17%

• LYMPHATIC SPREAD most common to upper, middle deep cervical & retropharyngeal lymph nodes.

Diagnostic Evaluation

Clinical evaluation

History takingPhysical examination:

-palpation of neck node-Testing of cranial nerve-Vision & hearing assesment-Examination for distant metastasis:palpation of abdomen chest & spine.

CRANIAL NERVE TESTING

The Olfactory nerve (CN I) is simply tested by offering something familiar for the patient to smell and identify.

Olfactory nerve test

fundoscopy should be performed on both eyes.

Visual reflexes comprise direct and concentric light reflexes. -

• OPTIC NERVE TESTING

Occulomotor, trochlear & abducens nerve testing

• The Oculomotor nerve ( III), Trochlear nerve (IV) and Abducent Nerve (VI) are involved in movements of the eye. They supply the extraocular muscles of eye.

Trigeminal nerve (CN V) is involved in sensory supply to the face and motor supply to the

muscles of mastication

Corneal reflex

The corneal reflex should also be examined as the sensory supply to the cornea is from this nerve. Do this by lightly touching the cornea with the cotton wool. This should cause the patient to shut their eyelids.

To test the motor supply, ask the patient to clench their teeth together, observing and feeling the bulk of the

masseter and temporalis muscles.

perform the jaw jerk on the patient by placing your left index finger on their chin and striking it with a tendon hammer. This should cause slight protrusion of the jaw.

Crease up the forehead

The Facial nerve (CN VII) supplies motor branches to the muscles of facial expression. -

Keep eyes closed against resistance

Puff out the cheeks Reveal the teeth

Vestibulocochlear (VIII) nerve test

Rinne test - place tuning fork on the mastoid process .

Webers test - place the tuning fork at centre of the forehead -

Rinne test - place tuning fork beside the ear

Glossopharyngeal nerve (IX) test• The Glossopharyngeal

nerve (CN IX) provides sensory supply to the palate. It can be tested with the gag reflex or by touching the arches of the pharynx.

vagus nerve (CN X) provides motor supply to the pharynx. Ask the patient to speak .The uvula should be observed

before and during the patient saying “aah”. Check that it lies centrally and does not deviate on movement.

Spinal acessory nerve(XI) test

Sternocldeiomastoid ms. test against resistance

Trapezius ms. test against resistance

Hypoglossal nerve (XII) test

Ask the patient to stick their tongue out. If the tongue deviates to either side, it suggests a weakening of the muscles on that side.

Radiologic evaluation

• Nasopharyngoscopy• X Ray head & neck • CT scan head & neck ( for evaluation &

treatment planning ) • MRI ( if intracranial extension )• Bone scan• Pet scan

Endoscopic nasopharyngoscopy

MRI.

Advantages: Superior in assessingprimary tumour, invasion intosurrounding soft tissuepharyngobasilar fascia,skull base invasion,intracranial invasion, aswell as cavernous sinusextension andperineural disease

Advantages:Superior to MRI and CT

forassessing lymph nodemetastasis, especiallycervical nodal

metastases,and distant metastases,especially occult

metastatic disease

PETCTImaging techniques

Histopathologic evaluation

• Biopsy• Most common site are roof of nasophalynx

& Rosenmuller fossa• Most common histological type:

squamous cell carinoma ( SCC)KERATINIZING TYPE NON KERATINIZING TYPE –diffretiated & undiffentiated subtypesBASALOID TYPE

Immunology

• Indirect immunofluorescence for IgG & IgA antibodies to viral capsid antigen (VCA) & early antigen (EA)– Most specific test for diagnosis– Highly predictive of the clinical

course:monitoring of EBV DNA in serum of affected pt.using RTPCR is useful for monitoring therapy.

– not yet commercially available