Bundhit Tantiwongkosi, MDFrank R. Miller, MD

University of Texas Health Science Center San Antonio, TX

Annual Scientific Meeting American Society of Neuroradiology

Chicago, IL

April 25-30, 2015

T4a versus T4b of Head Neck Cancers: Current Concepts beyond Resectibility

Issues

Control #: 387eEdE#: eEdE-95

Control #: 387eEdE#: eEdE-95

7th Edition of American Joint Committee of Cancer (AJCC) staging defines T4a and T4b HN cancers as moderately advanced local and very advanced local disease respectively, instead of resectable and unresectable disease per the 6th edition

Differences between the two stages are greatly important because they dictate treatment options and patient prognosis

Introduction

Table of Content

Oral Cavity

Oropharynx

Larynx

Hypopharynx

References

Oral Cavity Cancer: T4a Mucosal Lips, Buccal Mucosa, Upper & Lower Alveolar Ridges, Retromolar Trigone, Floor of Mouth, Hard Palate, Anterior 2/3 Tongue

Structure involved Surgery

Extrinsic Tongue Muscles (A)

Glossectomy with 1 cm margins

Cortical Bone (B) Marginal or lingual mandibulectomy

Medullary Bone (C) Segmental mandibulectomy

Skin (D) Wide local excision with 1-2 cm margins

Maxillary Sinus (E) Infrastructure, partial or total maxillectomy

A

B

C

D

E

A: FOM cancer (↓) involves M. Genioglossus (→)

B: Oral tongue cancer (↑) involves lingual mandibular cortex (→)

C: RMT cancer (↓) involves mandibular medulla (→)

D: Mandibular alveolar ridge cancer (→)involves skin (↑)

E: RMT cancer (↑) involves maxillary sinus (→)

Surgery is followed by Radiation +/- CMT

Oral Cavity Cancer: T4bStructure involved Surgery

Masticator space Extended Total Maxillectomy/Mandibulectomy

Pterygoid plates Unresectable

ICA Carotid artery resection with possible bypass (often deemed unresectable due to high rate of stroke)

Skull base Skull base resection(usually not surgically possible)

Main treatment for T4b oral cavity cancer is chemoradiation with poorer local control when bone involvement occurs. Surgery options are limited as aboveA & B: Primary RMT cancer (→) involves M. Buccinator (↓) , M.

Medial Pterygoid (↑), M Massector, Pterygoid plates (←)

B

A

Oropharyngeal Cancer: T4aBase of Tongue (BOT), Palatine Tonsils, Soft Palate, Posterior Pharyngeal Wall : from hard palate to vallecula floor

Structure involved

Surgery

Extrinsic Tongue Muscles (A)

Glossectomy with 1 cm margins

Medial pterygoid muscle (B)

Extended Maxillectomy

Larynx (C)  Total laryngectomy

Hard palate (D,E) Infrastructure Maxillectomy

Mandible (not shown) Segmental Mandibulectomy

AA

B

C

D

E

A: BOT cancer (→) involves M. Genioglossus (←)

B: Oropharyngeal wall cancer (↑) involves M. Medial Pterygoid (←)

C: BOT cancer (↑) involves suprglottic larynx (←)

D&E: Palatine tonsil cancer (→) involves maxillary sinus (↑)

Both T4a and T4b OP cancers are treated with radiation first +/- CMT for organ preservation with possible surgical salvage for local failure in selected

patients.

Oropharyngeal Cancer: T4bStructure involved

Surgery

M. Lateral Pterygoid (A) Unresectable

Pterygoid plate (B) Unresectable

Skull base (C) Skull base resection 

(usually not surgically  possible)  Nasopharynx (D) Wide local excision with 1 cm margin

 (usually not feasible)

ICA (E) Carotid artery resection with possiblebypass (often deemed unresectable due to high rate of stroke)

A&B: Palatine tonsil cancer (→) involves M. Lateral Pterygoid (←) and pterygoid

plate (→)

C&D: Palatine tonsil cancer (↑) involves skull base (→) and lateral nasopharyngeal wall (←)

E: Palatine tonsil cancer extends to encase ICA 360 degrees (→)

Both T4a and T4b OP cancers are treated with radiation first +/- CMT for organ preservation with possible surgical salvage for local failure in

selected patients.

A D

B E

C

Larynx: T4aSupraglottic, glottic, subglottic

Structure involved Surgery

Through thyroid cartilage Total laryngectomy with thyroid lobectomy if involved 

Extralarngeal soft tissue (strap muscle, trachea, esophagus, thyroid, tongue)

Total laryngectomy with removal of involved tissues to achieve 1 cm margins (i.e. thyroid lobectomy; partial glossectomy; cervical esophogectomy)

Total laryngectomy is followed by radiation +/- concurrent CMT

A

B

A: Glottic cancer (→) involves through right thyroid cartilage

B: Glottic cancer (→) destroys the anterior aspect of the thyroid cartilage to involve the strap muscles and soft tissue

Larynx: T4bSupraglottic, glottic, subglottic

Structure involved Surgery

Prevertebral space Unresectable

Carotid artery Carotid artery resection with possible bypass (often deemed unresectable due to high rate of stroke)

Mediastinum Unresectable

Chemoradiation is the mainstay of treatment with limited surgical options

A

B

A&B: A large transglottic cancer (→) involves the left side of the

prevertebral space (↑)

Hypopharynx: T4aPostcricoid Region, Pyriform sinuses, Posterior Paryngeal Wall: From vallecular floor to inferior border of the cricoid ring

Structure involved Surgery

Thyroid/cricoid cartilages:

Laryngopharyngectomy

Central compartment soft tissue (strap muscle, subcutaneous fat)

Laryngopharyngectomy with resection of additional soft tissue to achieve 1 cm margins

Thyroid gland Laryngopharyngectomy with thyroid lobectomy

Chemoradiation is the treatment of choice in order to preserve organ function with the surgical options as above

A

B

A&B: Right pyriform sinus cancer (↑) invades through the right thyroid cartilage (←), right strap muscle (↓)and subcutaneous fat (→)

Hypopharynx: T4b

Structure involved Surgery

Prevertebral space Unresectable

Carotid artery Carotid artery resection with possible bypass (often deemed unresectable due to high rate of stroke)

Mediastinum Unresectable

Chemoradiation is the mainstay of treatment with limited surgical options

A&B: Right pyriform sinus cancer (↑) involves the aryepiglottic fold (←),

crosses the midline and invades the right prevertebral space (↑)

Take Home Points T4a disease is anatomically resectable but patients often undergo

non-surgical treatment due to overall poor prognosis, poor performance status, or quality of life issues

T4b disease has limited surgical options and chemoradiation is the main treatment

Precise localization of tumor invasion is crucial in staging and treatment planning

AJCC establishes criteria of staging in each sub site that radiologists need to follow for uniform staging and follow up

Edge SB, et al. In: AJCC Cancer Staging Handbook 7rd ed. New York: Springer; 2009:39-126

D.M. Yousem, K. Gad, R.P. Tufano. Resectability Issues with Head and Neck Cancer AJNR Am J Neuroradiol November 2006 27: 2024

Ratko TA, Douglas GW, de Souza JA, Belinson SE, Aronson N. Radiotherapy Treatments for Head and Neck Cancer Update [Internet]. Rockville (MD): Agency for Healthcare Research and Quality (US); 2014 Dec. Available from http://www.ncbi.nlm.nih.gov/books/NBK269018/ PubMed PMID: 25590120.

Kodaira T, Nishimura Y, Kagami Y, Ito Y, Shikama N, Ishikura S, Hiraoka M. Definitive radiotherapy for head and neck squamous cell carcinoma: update and perspectives on the basis of EBM. Jpn J Clin Oncol. 2015 Mar;45(3):235-243. Epub 2014 Dec 9. Review. PubMed PMID: 25492926

Sharma S, Chaukar DA. International Federation of Head Neck Oncology Society 5(th) World Congress/American Head Neck Society 2014 update. Indian J Med Paediatr Oncol. 2014 Jul;35(3):228-30. doi: 10.4103/0971-5851.142041. PubMed PMID: 25336796; PubMed Central PMCID: PMC4202621

References

THANK YOU FOR VIEWING OUR PRESENTATION

Please send questions or comments to:

Bundhit Tantiwongkosi, MD

tantiwongkos@uthscsa.edu