Chapter 41 Nasopharyngeal Carcinoma Flashcards
Describe boundaries of Nasopharynx
Anterior Nasal cavity via posterior choanae
Inferior Oropharynx
Roof Basilar portion of sphenoid and occipital bones
Floor superior surface of soft palate and nasopharyngeal isthmus
Lateral Pharyngotympanic tube(Eustachian tube) opening
Posterior superior pharyngeal constrictor muscle, pharyngobasilar fascia, buccopharyngeal fascia
Describe torus tubarius
Formed by cartilage of pharyngotympanic tube elevating mucous membrane of lateral nasopharynx
Most common site of origin of nasopharyngeal malignancies
Fossa of Rosenmullar
Define sinus of Morgagni and structures that pass through it
Lateral area of muscular deficiency in superior pharyngeal constrictor muscle
Pharyngotympanic tube and levator veli palatini
What does proximity of foramen lacerum, foramen ovale, foramen spinosum, jugular foramen, hypoglosal canal, carotid space with sinus of morgagni signify?
Intracranial extension
Nerve supply of Nasopharynx
Afferent innervation
-anterior to pharyngotympanic tube orifice V2(Trigeminal nerve)
-posterior to tubal orifice Glossopharyngeal nerve
Motor innervation
-Pharyngeal branch of IX, X and sympathetic fibers from superior cervical ganglion
Blood supply of Nasopharynx
Arterial supply
Ascending Pharyngeal artery
Sphenopalatine artery
Artery of pterygoid canal
Venous drainage
Pharyngeal plexus drains into internal jugular vein, directly or via communication with pterygoid plexus
Bimodel distribution of Nasopharynx in low risk and high risk
Low risk
1st peak 15-25 years
2nd peak 50-59 years
High risk
4th and 5th decade of life
Most prevalent cases of Nasopharynx in the world
Hong Kong and Guangdong Province in southern China
26.9 per 100,000 people per year
3 major cause of Nasopharyngeal Carcinoma
- Genetic - Gene closely linked to HLA locus
- Environmental - high salt, alcohol, smoking, exposure to dust,fumes,formaldehyde
- Viral - EBV
Proteins predominantly expressed in NPCA induced by EBV infection
Latent Membrane Protein (LMP1, LMP2A, LMP2B)
EBV determined nuclear antigens(EBVA1, EBVA2)
Name principle oncogene which play likely etiologic role for EBV in NPC
LMP1 Latent Membrane Protein 1
Foramina of base of skull and associated anatomic structure
Cribiform plate
olfactory nerve
ant ethmoidal artery
Optic foramina
Optic nerve
Opthalmic artery
Superior orbital fissure
III,IV,V1,VI Ophthalmic vein orbital branch of middle meningeal and recurrent branch of lacrimal arteries sympathetic plexus filaments from carotid plexus
Foramen rotundum
V2
Foramen ovale
V3
accessory meningeal artery
lesser superficial petrosal nerve
Foramen lacerum
internal carotid sympathetic carotid plexus Vidian nerve meningeal branch of ascending pharyngeal artery Emissary vein
Foramen spinosum
Recurrent branch of V3 nerve
Middle meningeal artery and vein
Stylomastoid foramen
Facial nerve
Internal acoustic meatus
Auditory nerve VIII
Internal auditory artery
Jugular foramen
IX,X,XI
Inferior petrosal sinus
Transverse sinus
Meningeal branches from occipital and ascending pharyngeal arteries
Hypoglosal canal
XII
Meningeal branch of ascending pharyngeal artery
Foramen magnum
Spinal canal
Spinal accessory nerve
Vertebral vessels
Anterior and posterior spinal vessels