Chapter 41 Nasopharyngeal Carcinoma Flashcards Preview

Perez and Brady's Principles and Practice of Radiation Oncology 6th Edition > Chapter 41 Nasopharyngeal Carcinoma > Flashcards

Flashcards in Chapter 41 Nasopharyngeal Carcinoma Deck (61):
1

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

2

Describe torus tubarius

Formed by cartilage of pharyngotympanic tube elevating mucous membrane of lateral nasopharynx

3

Most common site of origin of nasopharyngeal malignancies

Fossa of Rosenmullar

4

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

5

What does proximity of foramen lacerum, foramen ovale, foramen spinosum, jugular foramen, hypoglosal canal, carotid space with sinus of morgagni signify?

Intracranial extension

6

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

7

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

8

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

9

Most prevalent cases of Nasopharynx in the world

Hong Kong and Guangdong Province in southern China
26.9 per 100,000 people per year

10

3 major cause of Nasopharyngeal Carcinoma

1.Genetic - Gene closely linked to HLA locus
2.Environmental - high salt, alcohol, smoking, exposure to dust,fumes,formaldehyde
3.Viral - EBV

11

Proteins predominantly expressed in NPCA induced by EBV infection

Latent Membrane Protein (LMP1, LMP2A, LMP2B)
EBV determined nuclear antigens(EBVA1, EBVA2)

12

Name principle oncogene which play likely etiologic role for EBV in NPC

LMP1 Latent Membrane Protein 1

13

Foramina of base of skull and associated anatomic structure
Cribiform plate

olfactory nerve
ant ethmoidal artery

14

Optic foramina

Optic nerve
Opthalmic artery

15

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

16

Foramen rotundum

V2

17

Foramen ovale

V3
accessory meningeal artery
lesser superficial petrosal nerve

18

Foramen lacerum

internal carotid
sympathetic carotid plexus
Vidian nerve
meningeal branch of ascending pharyngeal artery
Emissary vein

19

Foramen spinosum

Recurrent branch of V3 nerve
Middle meningeal artery and vein

20

Stylomastoid foramen

Facial nerve

21

Internal acoustic meatus

Auditory nerve VIII
Internal auditory artery

22

Jugular foramen

IX,X,XI
Inferior petrosal sinus
Transverse sinus
Meningeal branches from occipital and ascending pharyngeal arteries

23

Hypoglosal canal

XII
Meningeal branch of ascending pharyngeal artery

24

Foramen magnum

Spinal canal
Spinal accessory nerve
Vertebral vessels
Anterior and posterior spinal vessels

25

Structures locally infiltrated by NPC anteriorly.

Nasal fossa - lateral wall invasion can lead to involvement and destruction of pterygoid plates
Less common - posterior ethmoid and maxillary sinus
Advanced stage - orbital apex, inferior orbital fissure

26

Structures locally infiltrated by NPC superiorly and posteriorly

Superior
base of skull, sphenoid sinus, Clivus
foramen lacerum positioned directly above pharyngeal recess(fossa of Rosenmullar), merkel's cave,foramen ovale, petrous part of temporal bone

Posterior
Prevertebral muscle longus capitus

27

Structures locally infiltrated by NPC inferiorly

Oropharynx
Advanced disease - C1 vertebra

28

Structures locally infiltrated by NPC laterally

Parapharyngeal space along with invasion of levator and tensor veli palatini muscles
Advanced disease - invasion of pterygoid muscles, direct invasion or compression of internal carotid artery
Invade middle ear through pharyngotympanic tube

29

Lymphatic drainage of Nasopharynx

2 major lymph collectors that runs along lateral and posterior side of pharyngeal wall.
1.Lateral lymph collector drainage sites
Lateral pharyngeal node
Jugulodigastric/Subgastric node
3rd/4th/5th node of retropharyngeal group
2.Posterior lymph collector drainage sites
1st node of Retropharyngeal group(node of Rouviere)

30

Most common level of lymph node involved in NPC

Level IIb

31

Percentage of distant metastasis in NPC at presentation and during disease process.

At presentation : 3-6%
During disease process : 18-50%

32

Risk factor of distant metastasis in NPC

Advanced neck node metastasis esp low neck involvement

33

Most common site of distant metastasis in NPC

Most common : Bone

2. Lung
3. Liver

Brain and Skin : Rare

34

Clinical presentation of NPC

Upper neck mass
Mass in Nosopharynx : Epistaxis, Nasal obstruction
Skull base erosion : headache,cranial nerve palsy

35

Most common presenting symptom in NPC

Neck mass followed by nasal and aural symptoms

36

Cranial nerve frequently involved in NPC

VI 13.3%
V 7.8%
(Chai and Perez et al)

37

Ng et al How is MRI superior to CT in assessing tumor extent in NPC

Higher sensitivity for
skull base involvement(60% vs 40%)
Intracranial involvement(57% vs 36%)
RP node(58% vs 21%)
Tumor infiltration prevertebral muscles(51% vs 22%)

38

Van den Brekel et al LN mets radiologically defined in H&N as

Presence of central necrosis
ECS
Shortest axial diameter >=10mm
(11mm jugulodigastric node, 5mm RP node)
Cluster of 3 or more node that are borderline in size

39

Name 2 tumor markers for NPC

IgA anti VCA(Viral Capsid Antigen)
IgG anti-EA(Early Antigen)

40

Oropharyngeal extension T stage?

T1

41

Paranasal extension T Stage?

T3

42

Hypopharyngeal extension T stage?

T4

43

T4 stage extension in NPC

Intracranial extension
Cranial nerve involvement
Hypopharynx
Orbit
Infratemporal fossa/masticator space

44

T1N0 NPC stage?

Stage I

45

T2N1 NPC what stage?

Stage II

46

T3N2 NPC stage?

Stage III

47

T4N2 NPC stage?

Stage IVA

48

Any T N3 NPC stage?

IVB

49

Define boundaries of supraclavicular fossa?

Triangular region defined by
Superior margin of sternal end of clavicle
Superior margin of lateral end of clavicle
Point where neck meets the shoulder

50

Pathologic classification WHO 2005 NPC

Keratinizing SCC
Non Keratinizing SCC
Differentiated
Undifferentiated
Basaloid SCC

51

Which pathologic subtype of NPC strongly associated with EBV?

Non Keratinizing SCC

52

Most important prognostic factor in NPC

TNM staging

53

Poor prognostic factors in NPC

Bone erosion
Cranial nerve palsy
Lower nodal involvement
Extension to prestyloid space or anterior part of masticator space
Parapharyngeal space extension(controversial)
Prevertebral Space Involvement(PSI)
Gross volume of primary tumor(GTV-P)
Better prognosis for female and younger patients

54

Sensitivity and specificity of plasma EBV DNA for detecting NPC(Lo et al)

Sensitivity 96%
Specificity 93%

55

Clinical trials that found high pretreatment plasma EBV DNA level associated with advanced stage and poorer prognosis in NPC

Lo et al
Lin et al
Leung et al

56

Clinical trials that found posttreatment plasma EBV DNA level strong predictor of outcome in NPC

Le et al
Wang et al
An et al

57

Biologic markers expressed in NPC associated with prognosis

EGFR
HIF 1alpha
CA IX
VEGF

E-catherin and beta-catenin
c-erbB2
p53
NM23-HI
Interleukin-10

58

Local Control Rate NPC
T1-2 >70Gy vs 66-70Gy
T3-4 >70Gy
Perez et al

100% vs 80%
<55%

59

What is the most important radiation factor in NPC
Total dose or Dose fraction?

Total dose

60

Lee et al prophylactic neck irradiation in clinically negative neck vs untreated, what was the nodal recurrence rate in NPC?

11% vs 40%

61

Describe high risk subclinical CTV
(CTV59.4Gy) in NPC

GTV +
Entire Nasopharynx
Retropharyngeal node
Clivus
Skull base
Pterygoid fossa
Parapharyngeal space
Sphenoid sinus
Posterior 1/4th to 1/3rd of nasal cavity and maxillary sinus
Nodal regions: bilateral upper jugular,submandibular,subdigastric,midjugular,
posterior cervical,retropharyngeal.