Optimal surgical procedure for locally curative surgery in patients with anaplastic thyroid carcinoma: importance of preoperative ultrasonography.

Anaplastic thyroid carcinoma (ATC) is a very aggressive disease showing a high mortality. However, long-term survival is expected when patients do not show distant metastasis at diagnosis and undergo locally curative surgery. In this study, we investigated the optimal surgical procedure for locally curative surgery for ATC in a series of 34 patients. Twenty patients underwent total thyroidectomy but there were no detectable skip lesions of ATC in the contralateral lobe on pathological examination. Cause-specific survival (CSS) of Stage IVA or IVB patients who underwent limited thyroidectomy did not differ from that of those who underwent total thyroidectomy. Clinical node metastasis on ultrasonography was not detected in 15 patients but 11 of these patients underwent lymph node dissection. Three of these were node-positive on pathological examination but only one showed metastatic node of ATC that was involved in the primary lesion. Of 19 patients having clinical node metastasis, 10 were ATC node positive on pathological examination. Taken together, for locally curative surgery in ATC patients, 1) total thyroidectomy may not be mandatory unless patients have clinical lesions in the contralateral lobe; 2) prophylactic modified radical neck dissection may not be mandatory for patients who do not demonstrate clinical signs of lymph node metastasis; and 3) extensive and careful therapeutic node dissection may be required for patients demonstrating clinical signs of node metastasis.