Patients

After institutional review board approval, we retrospectively reviewed the medical records of patients with PTC who underwent TET from January 2015 to January 2021 in the Department of General Surgery in Beijing Friendship Hospital. In our institution, the records of thyroid cancer patients are maintained in a prospectively collected database. Criteria for inclusion in the study were as follows: 1) age ≥14 years, 2) PTC was diagnosed pathologically via examination of fine needle aspiration or surgical specimens, and 3) TET was performed as first-line treatment. We excluded patients with multiple primary malignancies, previous neck surgery; abnormal preoperative serum parathyroid hormone (PTH) or calcium concentration, and chronic renal failure. Those with incomplete clinicopathological data were also excluded. Patients were informed of the study content in both written and oral forms before the operation and signed informed consents. Patients were assigned to receive either the TOVA or BA according to patients’ preference or choices. This study was approved by the ethics committee and institutional review board of Beijing Friendship Hospital affiliated with Capital Medical University (number, 2021-P2-246-01) and written informed consent was signed by all patients. This study complied with the Declaration of Helsinki.

The following clinical and pathological data were recorded: patient age and sex; tumor number, size, location, and histopathology; surgical procedure; intraoperative neuromonitoring (IONM) findings; number of dissected lymph nodes; parathyroid status; parathyroid autotransplantation; recurrent laryngeal nerve invasion, vascular invasion, and background thyroid disease such as Hashimoto thyroiditis or nodular goiter.