Power point presentation of AJCC TNM Staging of thyroid 8th Edition

1. AJCC TNM Staging of
Thyroid 8th Edition
Presenter Dr. Kanato T

2. ANATOMY OF THYROID GLAND
 Thyroid gland includes 2 lobes and
isthmus.

3. Blood supply:
 sup. &
 inf. thyroid arteries
 Anatomy variant: thyroid ima artery,
in 1.5% to 12%, in frontnof the
trachea.
Lymph vessels: drain
 to prelaryngeal,
 pretracheal and
 paratracheal nodes.

4. Venous supply
 • Superior and
 middle thyroid v. drain into the internal
jugular
 • Inferior thyroid v. drains into the
brachiocephalic trunk

5. Neck Node
 The term central neck usually refers
to levels VI and VII
 whereas the lateral neck includes
levels I. II. III, IV, and V

6. TNM STAGING 8th Ed.

7. T1
 T1 Tumor <2 cm in greatest dimension limited to
the thyroid
 T 1a Tumor <1 cm in greatest dimension limited lo
the thyroid
 T lb Tumor >1 cm but <2 cm in greatest dimension
limited to the thyroid

8. T2
 T2 Tumor >2 cm but <4 cm in greatest
dimension limited to the thyroid

9. T3
 T3 Tumor >4 cm limited to the thyroid, or
gross extrathyroidal extension invading
only strap muscles
 T3a Tumor >4 cm limited to the thyroid
 T3b Gross extrathyroidal extension
invading only strap muscles (sternohyoid,
sternothyroid. thyrohyoid, or omohyoid
muscles) from a tumor of any size

10. T4
 T4 Includes gross extra thyroidal extension
 T4a Gross extra thyroidal extension invading
subcutaneous soft tissues, larynx, trachea,
oesophagus, or recurrent laryngeal nerve
from a tumour o f any size
 T4b Gross extra thyroidal extension invading
prevertebral fascia or encasing the carotid
artery or mediastinal vessels from a tumour of
any size

12. N

13. N
 NX Regional lymph nodes cannot be assessed
 NO No evidence of loco regional lymph node
metastasis
 N0a One or more cytological or histologically
confirmed benign lymph nodes
 N0b No radiologic or clinical evidence of loco
regional lymph node metastasis
 Metastasis to regional nodes
 N 1a Metastasis to level VI or VII (pretracheal.
paratracheal, or prelaryngeal/Delphian, or upper
mediastinal) lymph nodes. This can be unilateral or
bilateral disease.
 N 1 b Metastasis to unilateral, bilateral, or
contralateral lateral neck lymph nodes (levels I. II.
III. IV, or V) or retropharyngeal lymph nodes

14. M
 M0-No distant metastasis
 M1 -Distant metastasis is present,
involving distant lymph nodes, internal
organs, bones, etc.

15. Summary of Changes
 Definition of Primary Tumor (T)
 Minor extrathyroidal extension was removed from the definition of T3 disease. As a
result, minor extrathyroidal extension does not affect either T category or overall stage.
 T3a is a new category and refers to a tumor >4 cm in greatest dimension limited to the
thyroid gland.
 T3b is a new category and is defined as a tumor of any size with gross extrathyroidal
extension invading only strap muscles (sternohyoid, stemothyroid, thyrohyoid, or
omohyoid muscles).
 Unlike previous editions where all anaplastic tumors were classified as having T4
disease, the T category for anaplastic thyroid cancers will now use the same definitions
used for differentiated thyroid cancers.

16. Definition of Regional Lymph
Node (N)
 The definition of central neck (N 1a ) was expanded to include both level
VI and level VII (upper mediastinal) lymph node compartments.
 Previously, level VII lymph nodes were classified as lateral neck lymph
nodes (N1b).
 The pN0 designation is clarified as one or more cytologically or
histologically confirmed benign lymph node(s).

18. AJCC Prognostic Stage Groups
 Prognostic Factors Required for Stage Grouping: The age at diagnosis cut off
used for staging was increased from 45 years to 55 years.
 The definition of Stages I, II, III. IV was changed for patients older than 55 years
at diagnosis.
 Stage I now includes TI and T2 tumors if N0/NX and M0 in patients older than
55 years at diagnosis.
 Stage II now includes TI and T2 tumors if NI and T3a/T3b tumors with any N if
M0 in patients older than 55 years at diagnosis.
 Stage III now includes only T4a with any N, if M0 in patients older than 55 years
at diagnosis.
 Stage IV now includes T4b with any N, any M and M 1 with any T or N in
patients older than 55 years at diagnosis.

19. Group Staging..

20. Anaplastic
 With anaplastic carcinoma, intrathyroidal disease is stage IVA,
 Gross extrathyroidal extensión or cervical node metastases is stage IVB,
and
 distant metastases is stage IVC

21. Comparison of 7th and 8th Edition
7th Edition 8th Edition

22. Node
7th Edition 8th Edition

23. Staging
7th edition
8th edition

24. Anaplastic
7th Edition
8th Edition

25. Medullary
7th Edition 8th edition
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