Staging Criteria for Thyroid Cancer
[Radiology 2008; Donahue KP, et al. Initial staging of differentiated thyroid carcinoma: continued utility of posttherapy 131I whole-body scintigraphy. 246: 887-894]
| Age and Stage | Size | Location | Metastases | Survival % Papillary | Survival % Follicular |
| Under 45 years | 0 | ||||
| I | Any | Any | 0 |
97 | 95 |
| II | Any |
Any |
(+) |
93 | 90 |
| ≥ 45 years | |||||
| I | Less than 2 cm | 0 | 0 | 97 | 95 |
| II | 2-4 cm | 0 | 0 | 93 | 90 |
| III | Any size | Spread to nodes around the thyroid- prelaryngeal and or Delphian pre and or paratracheal nodes (N1a) | 0 | 83 | 69 |
| Tumor larger than 4 cm | 0 | 0 | |||
| IVa | Any size | Spread to nodes lateral cervical or superior mediastinal nodes (N1b) | 0 | ||
| Any size tumor with local invasion into subcutaneous soft tissues, larynx, trachea, esophagus, or recurrent laryngeal nerves | 0 | 0 | |||
| IVb | Tumor invades mediastinum or prevertebral fascia or encases carotid artery | Any | 0 | 39 | 41 |
| IVc | Any | Any | (+) |
TNM Classification System for Differentiated Thyroid Cancer
[AJR 2009; Park JS, et al. Performance of preoperative sonographic staging of papillary thyroid carcinoma based on the sixth edition of the AJCC/UICC TNM classification system. 192: 66-72]
| Category | Description |
| Tx | Primary tumor cannot be assessed |
| T0 | No evidence of primary tumor |
| T1 | Tumor is ≤ 2cm in greatest dimension and is
limited to the thyroid; T1a 1cm,
but ≤ 2cm |
| T2 | Tumor is >2 cm but ≤ 4cm in greatest dimension and is limited to the thyroid |
| T3 | Tumor
is > 4 cm in greatest dimension and limited to the thyroid or any
tumor with minimal extrathyroid extension such as extension to the
sternothyroid muscle or perithyroid soft tissues |
| T4a | Tumor of any size extends beyond the thyroid capsule to invade subcutaneous tissues, larynx, trachea, esophagus, or recurrent laryngeal nerve |
| T4b | Tumor invades prevertebral fascia or encases carotid artery or mediastinal vessels |
| Nx | Regional lymph nodes cannot be assessed |
| N0 | No regional lymph node mets |
| N1a | Metastases to level VI (pretracheal, paratracheal, and prelaryngeal or Delphian nodes) |
| N1b | Metastases to unilateral or bilateral cervical or superior mediastinal lymph nodes |
| Mx | Distant metastases cannot be assessed |
| M0 | No distant metastases |
| M1 | Distant metastases |
TNM Staging System [From: J Nucl Med 2012; Avram AM. Radioiodine scintigraphy with SPECT/CT: an important diagnostic tool for thyroid cancer staging and risk stratification. 53: 754-764]
Patients under 45 years of age
| Stage |
T |
N |
M |
| Stage I |
Any T |
Any N |
M0 |
| Stage II |
Any T |
Any N |
M1 |
Patients 45 years or older
| Stage |
T |
N |
M |
| Stage I |
T1 |
N0 |
M0 |
| Stage II |
T2 |
N0 |
M0 |
| Stage III |
T3 T1/T2/T3 |
N0 N1a |
M0 M0 |
| Stage IVA |
T1/T2/T3 T4a |
N1b Any N |
M0 M0 |
| Stage IVB |
T4b |
Any N |
M0 |
| Stage IVC |
Any T |
Any N |
M1 |
Thyroid Cancer Risk Assessment
TABLE 3
Thyroid
Cancer Risk Stratification [From: J Nucl Med 2012; Avram AM.
Radioiodine scintigraphy with SPECT/CT: an
important diagnostic tool for thyroid cancer staging and risk
stratification. 53: 754-764]
| ATA | Thyroid Cancer Risk Stratification | |
| Very low risk | Unifocal or multifocal microcarcinomas (< 1cm) | |
| MACIS score < 6, or TNM score: T1?2, N0, M0 (MACIS= (metastases, Age, Completeness of resection, invasiveness, size of tumor, staging system devloped at the Mayo Clinic) | ||
| In patients < 45 years old: tumors < 4 cm confined to the thyroid | ||
| Excludes tumors with aggressive histology* (tall cell, insular, columnar, diffuse sclerosing, trabecular solid, poorly differentiated variants of papillary carcinoma, Hurthle cell variant of follicular thyroid carcinoma) or vascular invasion | ||
| Low-risk (all criteria must be met) | In patients < 45 years old: MACIS < 6, or TNM score: any T any N, M0 | |
| In patients ≥ 45 years old: MACIS < 6, or TNM score: T2, N0, M0 | ||
| √ | No local or distant metastases | |
| √ | All macroscopic tumor has been resected | |
| √ | There is no tumor invasion of locoregional tissues or structures | |
| √ | The tumor does not have aggressive histology* or vascular invasion | |
| √ | If 131I is given, there is no 131I uptake outside the thyroid bed on the first post-therapy scan | |
| Intermediate/Moderate risk (any criteria) | In patients < 45 years old: tumors > 4 cm; macroscopic (> 1cm) N1a or N1b; T1?3, N1b, M0 | |
| In patients ≥ 45 years old: T3, N0, M0 or T1?3, N1a, M0 | ||
| MACIS score > 6 | ||
| Minimally invasive (microscopic capsular, but not vascular invasion) FTC < 4 cm | ||
| √ | Tumor with aggressive histology* or vascular invasion | |
| √ | Microscopic invasion of tumor into the perithyroidal soft tissues at initial surgery | |
| √ | Cervical lymph node metastases, or 131I uptake outside the thyroid bed on the post-therapy scan | |
| High-risk (any criteria) | In patients < 45 years old: T4a?4b, any N, M0, or any T, any N, M1 | |
| In patients ≥ 45 years old: any T, N1a?1b, M0, AJCC Stages IVA, IVB, IVC | ||
| FTC > 4 cm, or macroscopic invasive FTC | ||
| √ | Distant metastases | |
| √ | Macroscopic tumor invasion | |
| √ | Incomplete tumor resection | |
| √ | Thyroglobulinemia out of proportion to what is seen on the post-therapy scan |
