extrathyroidal extension
Invasion of thyroid cancer beyond the thyroid capsule into surrounding neck structures.
Full Definition
Extrathyroidal extension represents invasion of thyroid carcinoma through the thyroid capsule into adjacent cervical structures such as strap muscles, esophagus, trachea, or recurrent laryngeal nerve. This finding significantly impacts staging, prognosis, and surgical planning in thyroid cancer management. Minimal extrathyroidal extension involves invasion into strap muscles, while gross extension affects major neck structures. Pre-operative identification through imaging guides surgical approach and extent of resection. The presence and degree of extrathyroidal extension influence post-operative radioiodine recommendations and long-term surveillance strategies.
Usage
Usage note: Distinguish between minimal and gross extension as they have different staging implications.
In Context
- "Gross extrathyroidal extension into the esophagus required en bloc resection during thyroidectomy." — Operative report
- "Minimal extrathyroidal extension into strap muscles was confirmed on final pathology." — Pathology report