Thyroid Gland
51
Thyroid Gland (ICD‐O‐3 C73.9)
The classification applies only to carcinomas. There should be microscopic confirmation of the disease and division of cases by histological type. The following are the procedures for assessing T, N, and M categories: T categories Physical examination, endoscopy, and imaging N categories Physical examination and imaging M categories Physical examination and imaging
Regional Lymph Nodes The regional lymph nodes are the cervical and upper/superior mediastinal nodes.
TNM Clinical Classification T – Primary Tumour* TX T0
T1
Primary tumour cannot be assessed No evidence of primary tumour
Tumour 2 cm or less in greatest dimension, limited to the thyroid T1a Tumour 1 cm or less in greatest dimension, limited to the thyroid T1b Tumour more than 1 cm but not more than 2 cm in greatest dimension, limited to the thyroid T2 Tumour more than 2 cm but not more than 4 cm in greatest dimension, limited to the thyroid T3 Tumour more than 4 cm in greatest dimension, limited to the thyroid or with gross extrathyroidal extension invading only strap muscles (sternohyoid, sternothyroid, or omohyoid muscles) T3a Tumour more than 4 cm in greatest dimension, limited to the thyroid T3b Tumour of any size with gross extrathyroidal extension invading strap muscles (sternohyoid, sternothyroid, or omohyoid muscles) T4a Tumour extends beyond the thyroid capsule and invades any of the following: subcutaneous soft tissues, larynx, trachea, oesophagus, recurrent laryngeal nerve
Head & Neck
Rules for Classification
52
Head and Neck Tumours
T4b Tumour invades prevertebral fascia, mediastinal vessels, or encases carotid artery Note * Including papillary, follicular, poorly differentiated, Hurthle cell and anaplastic carcinomas.
N – Regional Lymph Nodes NX N0 N1
Regional lymph nodes cannot be assessed No regional lymph node metastasis Regional lymph node metastasis N1a Metastasis in Level VI (pretracheal, paratracheal, and prelaryngeal/Delphian lymph nodes) or upper/superior mediastinum N1b Metastasis in other unilateral, bilateral or contralateral cervical (Levels I, II III, IV, or V) or retropharyngeal
M – Distant Metastasis M0 No distant metastasis M1 Distant metastasis
pTNM Pathological Classification The pT and pN categories correspond to the T and N categories. For pM see page 8. pN0 Histological examination of a selective neck dissection specimen will ordinarily include 6 or more lymph nodes. If the lymph nodes are negative, but the number ordinarily examined is not met, classify as pN0.
Histopathological Types The four major histopathological types are: Papillary carcinoma (including those with follicular foci) ▪▪ Follicular carcinoma (including so‐called Hürthle cell carcinoma) ▪▪ Medullary carcinoma ▪▪ Anaplastic ▪▪
Thyroid Gland
53
Stage
Papillary and Follicular* under 55 years Stage I Any T Any N Stage II Any T Any N
M0 M1
Papillary or Follicular 55 years and older Stage I T1a,T1b,T2 N0 Stage II T3 N0 T1,T2,T3 N1 Stage III T4a Any N Stage IVA T4b Any N Stage IVB Any T Any N
M0 M0 M0 M0 M0 M1
Medullary Stage I Stage II Stage III Stage IVA
Stage IVB Stage IVC
T1a, T1b T2, T3 T1, T2, T3 T1, T2, T3 T4a T4b Any T
N0 N0 N1a N1b Any N Any N Any N
M0 M0 M0 M0 M0 M0 M1
Anaplastic Stage IVA Stage IVB Stage IVB Stage IVC
T1,T2,T3a T1,T2,T3a T3b,T4a,T4b Any T
N0 N1 N0,N1 Any N
M0 M0 M0 M1
Note * Including papillary, follicular, poorly differentiated, and Hurthle cell carcinomas.
Head & Neck
Separate stage groupings are recommended for papillary and follicular (differentiated), medullary, and anaplastic (undifferentiated) carcinomas:
54
Head and Neck Tumours
Prognostic Factor Grid – Papillary and Follicular Thyroid Carcinoma Prognostic factors for survival in differentiated thyroid carcinoma of follicular cell derivation Prognostic factors
Tumour related
Host related
Environment related
Essential
Extrathyroid extension (T category) M category Post‐treatment thyroglobulin
Age
Residual disease: R0, 1 or 2
Additional
N category Site of metastases BRAF V600E mutation
Gender
Extent of resection Iodine ablation Endemic goitre
New and promising
Molecular profile
Source: UICC Manual of Clinical Oncology, Ninth Edition. Edited by Brian O’Sullivan, James D. Brierley, Anil K. D’Cruz, Martin F. Fey, Raphael Pollock, Jan B. Vermorken and Shao Hui Huang. © 2015 UICC. Published 2015 by John Wiley & Sons, Ltd.
Prognostic Factor Grid – Medullary Cancer Prognostic factors
Tumour related
Host related
Environment related
Essential
Pre‐ and postoperative calcitonin and CEA
Age
Extent of resection
Additional
MEN Germline mutation Calcitonin doubling time
New and promising
Molecular profile