Incidental parathyroidectomy after thyroid surgery and relationship with postoperative hypocalcemia: a single tertiary center analysis.

Incidental parathyroidectomy (IP) is a complication seen at varying rates after thyroid surgery, and its relationship with postoperative hypocalcemia has not been clarified. In this study, our goal was to identify the frequency and risk factors for IP in a large patient cohort and assess its correlation with postoperative hypocalcemia. A total of 4052 patients who underwent thyroid surgery between 2008 and 2020 were reviewed retrospectively. The patients were divided into two groups, the IP and non-IP groups, and compared in terms of demographics, surgical procedures, pathological diagnosis, and specimen weight. The relationships between IP and hypocalcemia were also evaluated. There were 587 (14.5%) IPs out of 4052 cases. In these patients, mostly one gland was removed (84.6%), and 23.2% of these glands were intrathyroidal. The rate of transient hypocalcemia was 39.9%, and that of permanent hypocalcemia was 1.7%. Female gender, malignancy, lower preoperative thyroid volume, presence of central lymph node dissection, lower specimen weight, presence of autotransplantation and capsule invasion in malignant cases were determined to be risk factors for IP. After excluding hemithyroidectomy and autotransplantation, transient and permanent hypocalcemia were found to be significantly higher in cases with IP (p < 0.001). Multivariate analysis showed that female sex, no multinodular goiter, central dissection, and low thyroid volume were risk-adjusted independent variables. Our findings highlight the significant role of IP in postoperative hypocalcemia. Given that most IPs are located in the perithyroidal region, precise surgical dissection is vital to preserve parathyroid gland function and prevent IP and subsequent hypocalcemia.