Transoral endoscopic thyroidectomy by vestibular approach in Viet Nam: surgical outcomes and long-term follow-up.

Background: The transoral endoscopic thyroidectomy by vestibular approach (TOETVA) has been developed for early-stage thyroid cancer treatment as well as benign thyroid nodules worldwide including Viet Nam, with low rate of complications and excellent results. However, there has not been any comprehensive studies with a large number of patients and long-term follow-up in our country. Therefore, we conducted this study to evaluate the results of treatment by TOETVA for benign and malignant lesions of thyroid gland in Viet Nam.

Methods: A prospective study was performed on 326 eligible patients who underwent TOETVA due to thyroid cancer and benign thyroid nodules in Department of Oncology and Palliative Care, Hanoi Medical University Hospital from July 2018 to April 2021. The clinical, surgical, and pathological characteristics, postoperative complications, and visual analog scale (VAS, 0-10 cm) score in day 1, 4, and 7 after surgery, long-term oncological and surgical outcomes were recorded.

Results: The mean age was 36.9 ± 9.8 years. 231 patients (70.9%) were diagnosed with differentiated cancer and 95 patients (29.1%) were diagnosed benign tumors of thyroid gland. In the cancer group, 12 patients (5.2%) undergone TOETVA had T3b-intraoperative-stage diagnosis, 219 patients (92.2%) were diagnosed T1 according to AJCC 8th. After 1 month of surgery, among thyroid cancer patients, there was no abnormality reported by thyroid scintigraphy and neck ultrasound as well as in unstimulated-Tg and anti-Tg values. The mean number lymph-node dissected in the cancer group was 6.1 ± 4.1 (range 0-21 nodes). However, only 2.6 ± 1.8 metastasis nodes were discovered (range 1-8 nodes), and the maximum size of these nodes was less than 2 mm. 81 patients presented occult lymph-node metastasis among thyroid cancer patients with cN0 stage (account for 35%). The occult lymph-node metastasis was 34.2% and 50% in patients diagnosed with T1 and T3b groups, respectively. The median postoperative hospital stay was 5.4 ± 0.7 days. Postoperatively, transient hypoparathyroidism was recorded in 12 patients (4.8%), transient hoarse was noted in 9 patients (3.6%), and numb chin was identified in 7 patients (2.8%). No permanent complication was noted. VAS score on first postoperative day was 4.5 ± 0.8. Median follow-up time was 12 (3-25) months. No recurrence was recorded.

Conclusions: TOETVA is an innovative and revolutionary technique in the treatment of benign thyroid nodules, as well as early-stage differentiated thyroid cancer. The results of oncology, postoperative complications, and satisfied outcomes supported the wide application of TOETVA in Viet Nam.