Table 3.

A Clinically Based Approach to Staging in Differentiated Thyroid Cancer Using the Eighth Edition AJCC/TNM Update

	Distant metastasis	Gross ETE present?	Structures involved with gross ETE	T category	N category	Stage
<55 years	No	Yes or no	Any or none	Any	Any	I
	Yes	Yes or no	Any or none	Any	Any	II
≥55 years	No	No	None	≤4 cm (T1–2)	N0/Nx	I
					N1a/N1b	II
				>4 cm (T3a)	N0/Nx/N1a/N1b	II
		Yes	Only strap muscle (T3b)	Any	Any	II
			Subcutaneous, larynx, trachea, esophagus, recurrent laryngeal nerve (T4a)	Any	Any	III
			Prevertebral fascia, encasing major vessels (T4b)	Any	Any	IVA
	Yes	Yes or no	Any or none	Any	Any	IVB

The expected 10-year DSS estimates presented in this table are approximate figures based on a review of previously published retrospective studies evaluating the AJCC staging system and/or the prognostic importance of critical clinical features (age, gross extrathyroidal extension, cervical lymph node metastases, and distant metastases).