A Comparative Study of Robotic Versus Conventional Open Modified Radical Neck Dissection for the Papillary Thyroid Carcinoma with Lateral Neck Node Metastasis

Sang-Wook Kang, MD, So Hee Lee, MD, Haeng Rang Ryu, MD, Woong Youn Chung, MD. Department of Surgery, Yonsei University College of Medicine

Purpose: Since the introduction of endoscopic technique to thyroid surgery, several endoscopic lateral neck dissection trials have been conducted with the aim of avoiding a long cervical scar, and the recent introduction of surgical robotic systems has simplified and increased the precisions of endoscopic techniques. The aim of this study was to evaluate and compare the early surgical outcomes of robotic and conventional open modified radical neck dissection (MRND) for papillary thyroid carcinoma (PTC) with lateral neck node metastasis (LNM).
Patients and Methods: From January 2009 to May 2010, 165 patients with PTC underwent bilateral total thyroidectomy with ipsilateral MRND for PTC with LNM. Of these patients, 56 underwent a robotic procedure using a gasless, transaxillary approach (the robotic group; RG) and 109 a conventional open procedure (the conventional open group; OG). These two groups were retrospectively compared in terms of their clinicopathologic characteristics, early surgical outcomes, and surgical completeness.
Results: The RG was younger than the OG(35.8±9.1 vs. 46.1±13.0, P<0.0001). The operative time was longer in the RG than the OG(277.4±43.2 vs. 218.2±43.8min, P<0.0001). The number of retrieved lymph nodes were similar between the RG and OG.(37.3±12.8 vs. 39.4±14.1, P=0.359). The RG had smaller tumor size(1.14±0.59 vs. 1.49±0.80, P=0.004) and earlier stage than the OG(stage I:IVa = 80.4%:19.6% vs. 46.3%:53.7%, P<0.0001). The period of hospital stay after surgery was shorter in the RG than the OG(6.0±2.5 vs. 8±5.2, P=0.008). Compared with the OG, the complication-rate was not different. There was no abnormal uptake on RAI scans in the two groups. The mean level of serum Tg(TSH suppressed) were acceptable in the two groups. The patients who had >1 ng/ml of serum Tg were 3 and 7 in the RG, and OG, respectively(Tg level; 4.59±4.54 vs. 3.41±2.40).
Conclusions: Robotic MRND was found to be similar to conventional open MRND in terms of early surgical outcomes and surgical completeness but to offer an advantage of excellent cosmetic result. Based on our initial experiences, robotic MRND should be viewed as an acceptable alternative method in low risk PTC patients with lateral neck node metastasis.