ANATOMY OF NASOPHARYNX AND STAGING CORRELATION

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 [email protected] M-9160470564 ANATOMY OF CANCER NASOPHARYNX AND STAGING CORRELATION

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

3. Ammunitions CECT CEMRI PETCT NASOPHARYNGOSCOPY

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

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

6. IMAGING 9/22/2021 10

7. PET vs.MRI 9/22/2021 11 Mahatma Gandhi Cancer Hospital & Research Institute,Visakhapatnanm

8. PET vs.MRI 9/22/2021 12 Mahatma Gandhi Cancer Hospital & Research Institute,Visakhapatnanm

9. Unknown primary 9/22/2021 Mahatma Gandhi Cancer Hospital & Research Institute,Visakhapatnanm 13

10. Impact on radiotherapy 9/22/2021 Mahatma Gandhi Cancer Hospital & Research Institute,Visakhapatnanm 14 Elective nodal irradiation Nodal boost

11. TRIPLE FUSION PET CT MRI 9/22/2021 15 Mahatma Gandhi Cancer Hospital & Research Institute,Visakhapatnanm

12. Nasopharynx

13. Parapharyngeal space

14. Window settings for FORAMEN

15. 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

16. 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

17. SUPERIOR SPREAD

18. 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 )

19. INFERIOR SPREAD

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

21. POSTEROIR SPREAD

22. LYMPHATIC AND INNERVATION

23. Changes in staging

24. Changes in T staging

25. 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

26. 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 ).

27. 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 ).

28. 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

29. 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 ).

30. 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

31. 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).

32. T3-ANTEROIR SPREAD

33. 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

34. 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).

35. T4-Foramen lacerum involvement

36. CHANGES IN NODAL STAGING

37. 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

38. Nasopharynx-N1

39. 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

40. 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

41. 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

42. Nasopharynx-N3

43. Nasopharynx -INTRA PAROTID NODE

44. Radiation Oncologist and Radiologist