Papillary, Follicular, Hurthle Cell, Poorly Differentiated, and Anaplastic Thyroid Carcinoma pT4b TNM Finding v8

**Semantic type:** Finding

**Definition:** Gross extrathyroidal extension invading prevertebral fascia or encasing the carotid artery or mediastinal vessels from a tumor of any size. (from AJCC 8th Ed.)

**Synonyms:** - Differentiated and Anaplastic Thyroid Carcinoma pT4b TNM Finding v8 - pT4b