• RATT
• robotic
• surgical completeness
• thyroidectomy

Backgrounds - Nowadays trans-axillary robot-assisted total thyroidectomy (RATT) is worldwide accepted as a safe and effective procedure for the treatment of benign and some malignant thyroid diseases, but surgical completeness about RATT is still debated.
Materials and Methods - This prospective study aims to demonstrate that total thyroidectomy can be performed by single trans-axillary robot-assisted procedure, with same results in surgical completeness compared to conventional open thyroidectomy. Patients inclusion criteria for the present study were: non toxic multinodular goiter with biggest nodule < 6 cm in the major diameter, indeterminate thyroid nodule < 6 cm, well differentiated thyroid cancer less than 5 cm without local and/or distant metastasis. Each patient was evaluated by means of three blood specimens: TSH, AbTg, hs-Tg and a neck ultrasound performed preoperatively and three months postoperatively.
Results - From January 2017 to September 2019 we enrolled 100 patients: 50 consecutive female patients underwent robot assisted trans-axillary total thyroidectomy and 50 matched female patients who underwent conventional open thyroidectomy. The type of surgical procedure was chosen according to patient’s preference. We divided patients in subgroups based on the final histology: benign and malignant subgroup. There were no significant differences in terms of postoperatively values of hs-Tg levels in patients operated on with robotic thyroidectomy and open thyroidectomy either for benign and malignant subgroup (benign: 1,22+-1,254 ng/ml vs 0,654+-0,672 ng/ml, p=0,207; malignant: 2,116+-4,677 ng/ml vs 0,921+-1,819, p=0,256), despite the RATT group of benign patients had a significantly higher preoperative hs-Tg level (320,58+-709,197 ng/ml vs 222,781+-215,529 ng/ml, p=0,014). The postoperative thyroid remnant volume estimated by means of neck ultrasonography was not significantly different between the two groups, both for benign and for malignant subgroups (benign: 0,167+-0,250 ml vs 0,194+-0,111 ml, p= 0,717 and malignant: 0,202+-0,260 ml vs 0,154+-0,160 ml, p=0,366). We also analyzed the difference between the remnant volume of thyroid tissue ipsilateral to the axillary access VS the remnant on the contralateral side, the result was not significantly different for benign subgroup (p=0,302) neither for malignant subgroup (p=0,127). Moreover in the RATT group the thyroid remnant tissue of both side were equivalent if compared with an equivalency test either for both benign (inf.limit p=0,001, sup.limit p<0,0001) and malignant subgroups (inf.limit p=0,006, sup.limit p<0,0001).
Conclusions - Despite the small number of patients enrolled and the short-term follow-up, RATT confirm to be a safe technique for treatment of both, benign thyroid diseases and well differentiated thyroid cancer. In addition, it demonstrates to offer a comparable surgical completeness with open conventional procedure and it seems of not affecting the outcome. We performed RATT by a single trans-axillary access, therefor we would like to share our experience with other professionals who performed bilateral axillary approach or use an extra chest or peri-areolar incision to perform robot-assisted total thyroidectomy. We look forward for a long term follow up of these patients to evaluate oncological outcome.