Thyroid carcinoma invading the upper aerodigestive system.

Well-differentiated thyroid carcinoma infrequently invades the upper aerodigestive tract. However, when invasion occurs it is the source of significant morbidity and excess mortality. The most common structures invaded by thyroid carcinoma are the recurrent laryngeal nerves, larynx, pharynx, and esophagus, which can produce symptoms of airway insufficiency, dysphagia, and hemoptysis. Locally invasive thyroid carcinoma can often be successfully treated while preserving function of the upper airway. If the tumor involves only the wall of the larynx or trachea without intraluminal extension, "shaving" the tumor from the trachea or larynx will produce local control rates comparable to more radical and destructive procedures. Intraluminal extension is a more serious problem that usually requires resection of a portion of the aerodigestive tract. Even in this situation, partial laryngeal or tracheal resection with preservation of function might be possible and should be used. Adjuvant therapy using radioiodine or external beam radiotherapy should be considered an integral part of any treatment plan for these tumors. These modalities will significantly reduce the rate of local recurrence and control symptomatic local disease.