Differentiated Thyroid Cancer
4
Table 1. Ultrasound Features of Lymph Nodes Predictive of
Malignant Involvement
Sign Reported sensitivity % Reported specificity %
Microcalcifications 5–69 93–100
Cystic aspect 10–34 91–100
Peripheral vascularity 40–86 57–93
Hyperechogenicity 30–87 43–95
Round shape 37 70
Adapted with permission from the European yroid Association guidelines for cervical ultrasound
(Leenhardt L et al. Eur yroid J 2013;2(3):147-159.)
Table 2. AJCC 7th edition/TNM Classification System for
Differentiated Thyroid Carcinoma
Primary tumor (T)
T0 No evidence of primary tumor
T1a Tumor ≤1 cm, without extrathyroidal extension
T1b Tumor >1 cm but ≤2 cm in greatest dimension, without extrathyroidal
extension
T2 Tumor >2 cm but ≤4 cm in greatest dimension, without extrathyroidal
extension.
T3 Tumor >4 cm in greatest dimension limited to the thyroid
-or-
Any size tumor with minimal extrathyroid extension (e.g., extension into
sternothyroid muscle or perithyroidal so tissues).
T4a Tumor of any size extending beyond the thyroid capsule to invade
subcutaneous so tissues, larynx, trachea, esophagus, or recurrent laryngeal
nerve.
T4b Tumor of any size invading prevertebral fascia or encasing carotid artery or
mediastinal vessels
Regional Lymph Nodes (N)
N0 No metastatic nodes
N1a Metastases to Level VI (pretracheal, paratracheal, and prelaryngeal/Delphian
lymph nodes)
N1b Metastases to unilateral, bilateral, or contralateral cervical (Levels I, II, III,
IV, or V) or retropharyngeal or superior mediastinal lymph nodes (Level VII)
Distant metastases (M)
M0 No distant metastasis
M1 Distant metastasis
