ANATOMY OF NASOPHARYNX AND STAGING CORRELATION

1. RADIOLOGY FOR RADIATION ONCOLOGISTS
DR KANHU CHARAN PATRO
MD,DNB(RADIATION ONCOLOGY),MBA,FAROI(USA),PDCR,CEPC
HOD,RADIATION ONCOLOGY
Mahatma Gandhi Cancer Hospital And Research Institute, Visakhapatnam
drkcpatro@gmail.com M-9160470564
ANATOMY OF CANCER NASOPHARYNX AND STAGING CORRELATION

2. What does a radiation oncologist want?
• Clear identification
• Target
• OAR
• Good resolution
2

6. Ammunitions
• CECT
• CEMRI
• PETCT
• NASOPHARYNGOSCOPY

7. WHY MRI?
• Soft tissue delineation
• Marrow involvement
• Parapharyngeal extension
• Differentiating retropharyngeal node
• Perineural spread
• Optic chiasma
• Hippocampus

9. WHY PET?
• Sub centimeter node
• CUP
• Suspicious soft tissue involvement

10. IMAGING
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11. PET vs.MRI
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Mahatma Gandhi Cancer Hospital & Research
Institute,Visakhapatnanm

12. PET vs.MRI
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Mahatma Gandhi Cancer Hospital & Research
Institute,Visakhapatnanm

13. Unknown primary
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Mahatma Gandhi Cancer Hospital & Research
Institute,Visakhapatnanm
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14. Impact on radiotherapy
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Mahatma Gandhi Cancer Hospital & Research
Institute,Visakhapatnanm
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1.Elective nodal irradiation
2.Nodal boost

15. TRIPLE FUSION
PET
CT
MRI
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Mahatma Gandhi Cancer Hospital & Research
Institute,Visakhapatnanm

18. Nasopharynx

22. Parapharyngeal space

28. Window settings for FORAMEN

29. Boundary
• Anteriorly
• Posterior nares and posterior margin of nasal septum
• Inferiorly:
• Soft palate
• Superiorly:
• Basisphenoid and basiocciput
• Roof of the nasopharynx is called the vault (or fornix) of the pharynx, where the mucosa firmly
attaches to the sphenoid and pharyngobasilar fascia
• Posteriorly:
• C1 and C2
• Laterally
• The pharyngeal opening of the Eustachian tube is located in the centre of the lateral wall
• Lymphoid tissue aggregates, also known as the tubal tonsil occur around the opening of the
Eustachian tube
• The fossa of Rosenmüller lies between the posterior margin of the Eustachian tube and the
posterior wall of the nasopharynx

30. Nasopharynx-BOUNDARY
• The nasopharynx (asterix) and its
superior limit represented by the
basisphenoid (arrow) and the
clivus (arrowhead). Inferiorly, the
junction between nasopharynx
and oropharynx (red line) is
represented by a line between the
hard palate and the superior edge
of the anterior arch of C1

33. SUPERIOR SPREAD

34. LATERAL SPREAD
Contrast-enhanced T1- weighted MR images in a patient presenting with direct
lateral extension through the pharyngobasilar fascia to the prestyloid
compartiment of the parapharyngeal space (a, arrow), and the infratemporal
fossa, with infiltration of the pterygoid muscles (b, arrow)

35. INFERIOR SPREAD

36. • Axial post-contrast T1 weighted
MRI showing a bulky
nasopharyngeal carcinoma
with gross extension into the
right nasal cavity (arrows).
ANTEROIR SPREAD

37. POSTEROIR SPREAD

38. LYMPHATIC AND INNERVATION

39. Changes in staging

40. Changes in T staging

41. T1-Nasopharynx
• Axial post-contrast T1 weighted
magnetic resonance imaging
(MRI) showing a small
nasopharyngeal carcinoma
within the right lateral
pharyngeal recess (arrow).
• This is a frequent site for early
cancer

42. T1 Nasopharynx
• Localized to nasopharynx (T1).
• Axial contrast-enhanced T1-
weighted image shows small NPC
(short arrows) centered in left
Rosenmuller fossa (long arrow),
which is the most common site for
this cancer, and involving
posterior wall.
• Tumor is confined to
nasopharynx, and there is small
metastatic left retropharyngeal
node (curved arrow).

43. Nasopharynx-PREVERTEBRAL EXTENSION- T2
• Image obtained before treatment
shows NPC involving
nasopharyngeal mucosa,
centered in right Rosenmuller
fossa (straight arrow) with deep
posterior extension into longus
muscles (curved arrow).

44. T2-Nasopharynx- parapharyngeal extension
• Nasopharyngeal carcinoma
(NPC) with parapharyngeal
extension (T2).
• Axial contrast T1-weighted image
shows NPC (white arrows) with
left parapharyngeal extension and
involvement of parapharyngeal fat
space.
• Note normal levator palatini
muscle (red arrow), tensor palatini
muscle (blue arrow),
pharyngobasilar fascia (black
arrow), and fat space (yellow
arrow) on normal right side

45. T3- Nasopharynx
• Nasopharyngeal carcinoma with
prevertebral extension Axial
contrast-enhanced image shows
nasopharyngeal carcinoma
(straight arrows) with extensive
spread predominantly posteriorly
into longus muscles (arrowheads)
and clivus (T3) (curved arrows).

46. Nasopharynx- CLIVUS
• Patient presenting with a
nasopharyngeal tumor showing direct
superior extension and infiltration of
the sphenoid bone. a CT depicts small
skull base erosions, b whereas MRI,
in particular the non-enhanced T1-
weighted sequence without fat
saturation, shows a much more
important infiltration of sphenoid bone
marrow

47. T3-Nasopharynx- PPF
• Contrast-enhanced MRI shows
NPC invading pterygopalatine
fossa (circle), pterygomaxillary
fissure (arrow), and vidian canal
(arrowhead).
• This fossa can be located in the most
medial aspect of the pterygomaxillary
fissure on the axial images and
provides a route of tumor spread to
the orbit (via the inferior orbital
fissure), infratemporal fossa (via the
pterygomaxillary fissure), oral cavity
(via the pterygopalatine canal), nasal
cavity (via the sphenopalatine
foramen), foramen lacerum (via the
vidian canal) and middle cranial
fossa (via foramen rotundum).

48. T3-ANTEROIR SPREAD

49. T4 Nasopharynx
• Nasopharyngeal carcinoma
(NPC) with skull base invasion
and pterygoid sclerosis (T3).
• Axial CT bone window shows
large NPC filling nasopharynx and
nasal cavity with bony destruction
of sphenoid bone, including right
pterygoid base, which also shows
sclerosis (arrow).
• INTRACRANIAL-T4

50. Nasopharynx- cavernous sinus
• Coronal post-contrast T1
weighted MRI showing a
nasopharyngeal carcinoma with
direct infiltration through the
sphenoid body (long arrows) into
the sphenoid sinus (short arrows)
and right cavernous sinus (broken
arrows).

51. T4-Foramen lacerum involvement

52. CHANGES IN NODAL STAGING

56. Nasopharynx-N1
• Patient with retropharyngeal
metastatic cervical lymph node
(N1). Axial T1-weighted
contrastenhanced
• MRI shows metastatic node
(arrow) in left retropharyngeal
region, which is frequently first
echelon for nodal spread

57. Nasopharynx-N1

58. Nasopharynx-N1
• Patient with metastatic cervical
lymph node (N1).
• Axial T1-weighted contrast-
enhanced
• MRI shows metastatic node
(arrow) posterior to left upper
internal jugular vein, which is
common site for metastatic node
with or without retropharyngeal
nodal involvement

59. Nasopharynx-N2
• Axial post-contrast T1 weighted MRI in a
patient with nasopharyngeal carcinoma
showing bulky metastatic nodes in the
internal jugular chains (short arrows)
and right submandibular region (long
arrow).
• BILATERAL

60. Coronal T1-weighted post-contrast MR image demonstrates bilateral cervical
lymph node metastases. In the 8th edition AJCC staging system, bilateral
lymphadenopathy of ≤6 cm above the cricoid cartilage is designated as N2.
Nasopharynx-N2

61. Nasopharynx-N3

62. Nasopharynx-INTRA PAROTID NODE

65. Radiation Oncologist and Radiologist