head and neck cancer staging

1. Major changes in Head
and Neck cancer in 2018
By:
summar Mohamed elmorshidy
Supervised by:
Professor Dr: Samir shehata

2. Introduction
• Assigning the proper clinical and pathological stage is one of the key activities for clinicians
caring for those afflicted with cancer. Staging entails stratification into similar groups
based on anatomic and nonanatomic criteria to assist in estimating prognosis and planning
treatment.
• Head and neck oncology encompasses a group of malignancies that arise in the mucosal
surfaces of the upper aerodigestive tract (UADT), including the oral cavity, pharynx, larynx,
and paranasal sinuses, as well as cancers of the major and minor salivary glands.
• As such, the staging of malignancies arising in the UADT was defined in the American Joint
Committee on Cancer (AJCC) Staging Manual, seventh edition.

3. 7th edition AJCC staging
• Definitions for regional lymph node(N) and involvement and spread
to distant metastatic sites are uniform except for N staging of
nasopharyngeal carcinoma .
• In general ,stage I,II defines a relatively small 1ry tumor with
no regional lymph node involvement.
• Stage III and IV cancers include large 1ry tumors which may
invade underlying structures and or spread to regional lymph
nodes.
• In the 7th edition of AJCC ,the words resectable (T4a) and
unresectable( T4b) were replaced by moderately advanced and
very advanced.

4. 7th edition N staging
( all other sites) Nasopharyngeal

5. Traditional staging

6. Why need of new staging• For head and neck cancers that are largely treated using nonsurgical
modalities (eg, nasopharyngeal cancer), pathological staging data, such as
the number of involved lymph nodes or microscopic ENE, are seldom
available; therefore, such diseases are staged using only the clinical TNM
(cTNM) system.
• Cancers that are usually treated surgically (eg, oral cavity cancer [OCC])
provide robust pathological and clinical staging information; therefore,
separate cTNM and pathological TNM (pTNM) systems are described for
these situations.
• Appearance of new risk factors Since 1990, the incidence of cancers of
the tonsil and tongue base associated with HR-HPV has risen at an
alarming 5% per year in the United States and elsewhere.

8. Key Updates:
Restaging Pharyngeal cancers based on 3 subgroups:
(a)HPV (–) Oropharynx and Hypopharynx
(b)HPV (+) Oropharynx
(C)Nasopharynx (+/- EBV)
• Entirely new staging paradigm for HPV associated OPC
• New/Updated T staging for:
(a)Oral Cavity
(b)Nasopharynx
• Change in nomenclature/classification of “unknown primary” head & neck cancer
• Expanded staging for nodal disease – ENEc

9. Risk factors
• HPV infection: It is the cause of a distinct subset of HNSCCs that occur primarily in the
oropharynx.
• The proportion of HPV-positive (HPV+) OPCs is growing.
• HPV Type 16 (HPV16) is responsible for more than 90% of HPV+ OPCs. The time from first
oral HPV infection to the development of cancer is estimated to be more than a decade.
• Measures of sexual behaviour (number of vaginal and oral partners, history of genital warts)
have been associated with HPV+ OPC.
• Patients with HPV+ OPC are less likely to be smokers than HPV-negative (HPV-) patients.
However, approximately 50% of patients with HPV+ OPC have history of tobacco use.

10. • HPV infection carcinogenesis: The integration of HPV DNA into the host genome disrupts the
expression of factor E2, the transcriptional repressor of E6 and E7 viral proteins.
• E6 and E7 encode oncoproteins that bind and degrade p53 and retinoblastoma (Rb) tumour suppressors,
respectively.

11. Testing for HPV Status p16
• Must be simple, inexpensive, and reproducible – Needs to be available
worldwide
• Immunohistochemistry for overexpression of the tumor suppressor
protein p16
• Established, reliable surrogate biomarker
– Independent positive prognosticator for OPC
– Inexpensive, widely availability, easy to interpret
• OPC will now be staged according to 2 distinct systems, depending on
whether or not they overexpress p16
• p16 overexpression = diffuse >/=75% tumor expression, with at least
moderate
• (+2/3) staining intensity

12. Unique characteristic of HPV +ve Head &
Neck Cancer

13. HPV positive OPC Staging
• T Classification:
Largely unchanged except:
– Carcinoma in situ (Tis) removed
– T4b removed
• N Classification:
Difference between clinical and pathologic staging
– Clinical staging based on laterality and size of nodes
– Pathologic staging based on number of nodes
Obviously for surgical patients only – ENE not included
• M Classification: Unchanged
• Overall Stage: Drastic Change
– Stage IV reserved for M1 disease

21. Nasopharynx
• There are 2 changes in nasopharynx T classifications relating to
anatomic markers rather than depth of invasion (DOI) . The
previous T4 criteria “masticator space” and “infratemporal fossa”
were used as synonyms, but their anatomic descriptions differ, sowing
confusion among clinicians. These terms will now be replaced by a
specific description of soft-tissue involvement to avoid ambiguity.
• In addition, adjacent muscle involvement (including medial
pterygoid, lateral pterygoid, and prevertebral muscles)
will now be “downstaged” to T2 based on a recent analysis
showing them to have a more favorable outcome using
current treatment

25. UnKnown primary
• Squamous cell carcinoma in lymph nodes arising from an undetected
primary cancer is a well recognized clinical entity in the head and neck.
• The typical presenting finding is of an enlarged cervical lymph node
with carcinoma identified by biopsy. A search through history, physical
examination, appropriate imaging, and biopsy of candidate sites must
yield no evidence of a primary tumor. These patients are categorized
as T0 but cannot be assigned to a specific anatomic site.
• Currently, greater than 90% of these T0 (unknown primary)
designations (lymph nodes in patients with no detectable primary)
reflect HR-HPV–associated cancers.
• A large majority of nasopharyngeal cancers are positive for Epstein-
Barr virus (EBV) by Epstein-Barr– encoded RNA (EBER) on ISH.

26. Unknown primary
• Recommending HPV-ISH, p16 immunohistochemistry, and EBER-
ISH on
pathologic analysis of all unknown primary cervical LNs.
• T0 designation being reserved only for virally mediated metastatic
carcinoma (i.e. ability to localize subsite by viral expression)
– HPV + OPC and NPC
• All HPV negative and EBV negative metastatic carcinoma to be
staged according to the system detailed in the cervical node and
unknown primary guidelines.
– The primary could be from ANY mucosal or epithelial site.

27. UnKnown Primary
• Cervical lymph node metastases that are HR-HPV ISH-
positive/p16-positive with no primary tumor identified through
history, physical examination, or available imaging studies will be
staged as p16-positive, HR-HPV– associated OPC, which includes a
T0 category. EBV-positive cancers identified in a cervical lymph
node with no detected primary tumor will be staged according to
the nasopharynx classification in which the T0 category remains.
• Squamous carcinoma in a cervical lymph node that is negative for
EBER and p16 cannot be assigned to any specific head and neck
primary site and will be staged according to the system detailed in
the cervical node and unknown primary chapter.

31. Changes to the T Category(oral cavity
cancer)