Standardization of Hybrid-vans (tori Method) for Thyroid Differentiated Cancer Including Invasion to the Trachea

Masayuki Tori, MD, Hiroki Akamatsu, MD, Takeshi Omori, MD, Katsuhide Yoshidome, MD, Toshirou Nishida, MD. Endocrine Surgery, Osaka Police Hospital

Background and Aim: Video-assisted neck surgery (VANS) has not been established, because it cannot be applied to invasive cases and to radical lymph nodes dissection which needs enough view and lift-up of the trachea. And moreover, when trachea is invaded by thyroid cancer, proper instruments are not usually available in VANS. On the other hand, small-incision surgery has a problem of operative window and isolation of back side of the thyroid bed with incomplete view. Therefore, we newly developed sophisticated Hybrid-VANS (HVANS: Tori method) which is a reasonable mixture of endoscopic surgery and small-incision procedure. We would present a novel HVANS thyroidectomy as a standard procedure for thyroid cancer which can be applied to all cases of thyroid cancer (<4cm) including LN metastasis and/or tracheal invasion. Patients and methods: Since April, 2011, HVANS was performed with 46 malignant cases. As to the operative indication, tumor size is <4cm and in trachea invasion cases, invasion is preoperatively thought to be treated by shaving. They consist of 44 papillary ca and 2 follicular ca. (groupA). These cases were clinically compared with the former conventional cases for three years (n=148, April, 2008 – Mar, 2011) (groupB). Evaluation of cosmetics and pain scale were added to the results. Op procedures: Single small color incision (1.5-2.0cm) is made just above the clavicle of the tumor side followed by insertion of one port (5mm) for scope 3cm below the clavicula. To obtain enough working space, anterior neck muscles are isolated after dissection of subcutaneous space, taped and pulled toward the head supported by L-shaped steel lift fixed to the operating table, and at the same time, thyroid lobe is pulled upward using thread support. Then mini-mini wound retractor is installed. That is how recurrent nerve and parathyroid are clearly visible. Lymph nodes dissection and anterior approach for the thyroid (ligation and cut of the isthmus, etc.) is performed directly through the incision, followed by isolation of inferior laryngeal nerve and ligation and cut of superior thyroid vessels with monitor of endoscope. Result: (groupA) Average operation time: lobectomy+CLND (central); 113min (n=33), lobectomy+MRND; 137min (n=5), total thyroidectomy+CLND; 216min (n=8, shaving of the trachea 3). Average blood loss <50ml (all cases). Postoperative course was all uneventful. Namely, Blood loss was very little. No complications including recurrent nerve palsy were encounterd. Average hospital stay was 4.6days. Those results were not significantly different from the data of groupB in each. In terms of cosmetics and pain, group A was superior to group B. Conclusion: Our findings support the idea that HVANS is a feasible, practical and safe procedure, with excellent cosmetic benefits. HVANS has come to be a standard operative procedure for thyroid differentiated cancer including invasion to the trachea.