1. The Surgical Completeness of Robotic thyroidectomy : A prospective Comparative Study of Robotic versus conventional open thyroidectomy in papillary thyroid carcinoma patients Sohee Lee M.D., Seulkee Park M.D., Cho Rok Lee M.D., Haiyoung Son M.D., Jungwoo Kim M.D., Sang-Wook Kang M.D., Jong Ju Jeong M.D., Kee-Hyun Nam M.D., Woong Youn Chung M.D. and Cheong Soo Park M.D. Department of Surgery Yonsei University Health System, Seoul, Korea

2. Conventional open thyroidectomy with direct approach through the neck Most Effective and safe method Noticeable scar in highly visible area Introduction

3. Robotic thyroidectomy via transaxillary approach Excellent cosmesis Short term outcome : comparable with conventional open thyroidectomy in low risk papillary thyroid cancer patients Introduction

4. The oncologic safety with surgical radicality of robotic thyroidectomy should be prior to cosmesis in managing thyroid cancer Robotic thyroidectomy via trans axillary approach has been criticized about complete excision of contralateral lobe The aim of this study : to show the surgical completeness of robotic thyroidectomy by comparing with conventional open thyroidectomy in papillary thyroid carcinoma Introduction

5. 110 patients with papillary thyroid carcinoma were enrolled from April, 2009 through February 2011 All underwent total thyroidectomty and 30 mci RAI ablation therapy 55 underwent conventional open thyroidectomy 55 underwent robotic thyroidectomy Definite extrathyroidal tumor invasion, lateral neck node metastases, perinodal infiltration at a metastatic lymph node, or distant metastasis were excluded Patients and Methods

6. Tumor located in the thyroid dorsal area (particularly at the tracheoesopheal groove) with posterior capsular invasion or extension to an adjacent structure were also excluded in robotic thyroidectomy Extent of surgery : According to the ATA guidelines Prophylactic ipsilateral CCND : performed for all the patients 12 patients were excluded ( ex. pregnancy, pt’s refusal) : three open thyroidectomy nine robotic thyroidectomy Analysis of surgical completeness : Radioiodine uptake Postoperative serum Tg level Patients and Methods

7. Radioactive iodine uptake calculate RAI uptake (%) in thyroid bed area (thyroid/whole body, thyroid/brain) 30mci RAI ablation therapy at postoperative 2~3 months Diagnostic scan at 1 year after 1 st RAI ablation Before 131-I Tx, at least 3-4 weeks Levothyroxine withdrawal with low iodine diet or rhTSH administration pre RAI TSH level > 30 μIU/mL Patients and Methods

8. Serum Tg level TSH stimulated Tg at 1 st RAI ablation and diagnostic scan TSH suppressed Tg : 6 month after RAI therapy The patient’s clinicopathologic characteristics, surgical outcomes, RAI uptake, serum Tg level were compared between the two groups. Patients and Methods

9. Conventional open thyroidectomy (N=52) Robotic thyroidectomy (N=46) P value Age(year) 48.3±10.640.4±10.4 <0.001 Gender M:F (ratio) 11:413:430.046 Operation time(min) 95.3±26.5130.3±29.9 <0.001 Tumor maximal size(cm) 1.03±0.541.02±0.43 0.943 Extracapsular invasionNo9(17.3%)5(10.9%)0.402 Yes43(82.70%)41(89.1%) MultiplicityNo36(69.2%)47(58.7%)0.299 Yes16(30.8%)19(41.3%) BilateralityNo49(94.2%)45(97.8%)0.620 Yes3(5.8%)1(2.2%) T stage19(17.3%)5(10.9%)0.402 343(82.7%)42(89.1%) N stage025(49.0%)27 (58.7%)0.416 1a22(41.5%)19(41.3%) Stage121(41.2%)32(69.6%)0.008 330(58.8%)14(30.4%) Results

10. Conventional open thyroidectomy (N=52) Robotic thyroidectomy (N=46) P value Retrieved central node number (N) 6.3±4.24.9±2.9 0.074 Radioactive iodine uptake at 30mci RAI ablation Thyroid bed/ Brain ratio 9.122±9.51623.510±34.7860.009 Thyroid bed/ Whole body ratio 0.044±0.0470.097±0.083<0.001 Radioactive iodine uptake at diagnostic scan after 1 st ablation† Thyroid bed/ Brain ratio 1.574±1.0211.480±0.5770.580 Thyroid bed/ Whole body ratio 0.007±0.0040.008±0.0040.455 Stimulated serum Tg level at 30mci RAI ablation(ng/ml) 3.17±8.935.66±7.510.141 Suppressed serum Tg level after 1 st ablation(ng/ml) 0.27±0.3230.38±0.61 0.275 Stimulated serum Tg level at diagnostic scan(ng/ml) 1.84±7.673.35±9.10 0.385 Results † Diagnostic scan was performed at 12months later after 1 st RAI ablation

11.  Robotic thyroidectomy showed significant high uptake at RAI ablation therapy compared with conventional open thyroidectomy.  However, stimulated Tg level at RAI therapy showed no significant difference between two groups.  Remnant thyroid tissue after robotic thyroidectomy can successfully managed by 30mci RAI ablations. (RAI uptake, stimulated Tg at diagnostic scan show no differences between two groups.)  Robotic thyroidectomy is safe and feasible in managing low risk papillary thyroid carcinoma patients Conclusion

12. Thank you for your attention