Endocrine Abstracts

The experience and expertise of a thyroid surgery team is a relevant factor in the development of postsurgical hipoparathyroidism (hypoPP). In 2005, we published a 9.6% prevalence of permanent hipoparathyroidism among patients operated on for thyroid cancer (TC) at our centre between 1985 and 2001. Since 2002, an expert surgery team was implemented as part of a multidisciplinary committee. The aim of the present study is to assess the prevalence and risk factors associated with permanent hypoPP after total thyroidectomy (TT) because of TC after the expert surgery team was introduced.

Methods: Retrospective analysis of a cohort of 56 patients attended consecutively in an endocrinology clinic between January and March 2018, having been operated on for TC from 2002 onwards and who had at least one-year follow-up since surgery (TT). Prevalence of transient (up to 6 months), prolonged (up to 12 months) and permanent (>12 months) after surgery hypoPP was calculated. Uni and multivariant logistic regression analysis were used adjusting for confounding variables and the Odds Ratio (OR) (95% CI) of presenting hypoPP was estimated. It was considered significant when P<0.05.

Results: 56 individuals were included (41 F, 15 M), average age (SD): 49 (13.9) years old. TT was undergone by an expert surgery team in 34 cases (60.7%). In 35 cases (62.5%) TT + lymphadectomy (LF) was performed: 18 central and 17 central + lateral. In 7 cases (12.5%), a two-stages TT was conducted. Overall, 1 (1.8%) patient presented permanent hypoPP, 4 (7.1%) prolonged hypoPP and 22 (39.3%) transient hypoPP. The univariate analysis showed the risk of developing hypoPP immediately after surgery was greater if LF (OR: 5.4 (1.6–18.2)), extrathyroid extension (OR 5.8 (1.5–21.2)) or lymph node metastases (OR 8 (1.9–33)) were present. The multivariant analysis (adjusted for local extension, performing LF and presence of lymph node metastases) revealed that surgery by the expert team reduced the risk of hypoPP with an OR of 0.18 (0.04–0.82). This model explained 44% of the variability of the risk estimation.

Conclusions: The presence of locoregional extension and the performance of lymphadectomy are predictive factors of postsurgical hypoPP in patients undergoing total thyroidectomy due to thyroid cancer. The implementation of an expert surgical team was independently associated with an 80% risk reduction of postsurgical hypoPP. Based on these results, centres where thyroid cancer surgery is performed, should implement an expert surgical team, coordinated within a multidisciplinary committee, for surgical management of this pathology.