Department of Endocrine Oncology and Nuclear Medicine, Maria Skłodowska-Curie National Institute of Oncology - National Research Institute, Warsaw, Poland.
Department of Haematology, Institute of Haematology and Transfusion Medicine, Warsaw, Poland.
Endokrynol Pol. 2020;71(2):126-133. doi: 10.5603/EP.a2020.0006. Epub 2020 Mar 10.
Inadvertent removal of, or damage to the parathyroid glands in the course of operations on the anterior neck compartment are responsible for over 80% of cases of chronic hypoparathyroidism (HypoPT). This study searched for factors related to the development of permanent HypoPT after total thyroidectomy and central neck lymphadenectomy in patients with thyroid carcinoma.
In total, 89 of 103 screened patients met the study's criteria and were put under prospective one-year observation. Demographic and surgical factors as well as the biochemical parameters of mineral homeostasis, controlled both preoperatively and postoperatively, were subject to statistical analysis. In line with contemporary guidelines, postoperative hypocalcaemia, rather than an abnormally low serum parathormone (PTH) concentration, was considered a diagnostic criterion of HypoPT.
On postoperative day one (POD1), serum concentration of PTH decreased below the normal range (< 12 pg/mL) in 29 patients and was undetectable in 19 patients (< 6 pg/mL). At one year postoperatively, 12 patients with undetectable POD1 PTH required treatment for hypocalcaemia and were diagnosed with permanent hypoPT. All the other patients regained normocalcaemia. Relative risk of permanent HypoPT associated with undetectable POD1 PTH was 88.75. A significant difference in median POD1 serum calcium concentration between the patients with undetectable POD1 PTH and those with detectable POD1 PTH was found (p < 0.001). The difference between the POD1 serum calcium in patients with permanent or transient HypoPT in the subgroup with undetectable POD1 PTH did not reach the level of statistical significance (median, 1.82 mmol/L vs. 1.96 mmol/L). At one month postoperatively, in patients who later developed permanent HypoPT, serum calcium was lower than it was in all other patients (p = 0.167). At one year postoperatively, serum concentration of PTH was in the normal range in 10 of 12 patients with permanent HypoPT; however, it was significantly lower than it had been before the operation and distinctly lower than it was in patients who regained normocalcaemia. The number of parathyroid glands either dissected or autotransplanted did not affect the development of permanent HypoPT.
Undetectable POD1 PTH is an important risk factor of permanent HypoPT. The main cause of permanent HypoPT was irreversible damage to the left in situ parathyroid glands.
在颈部前区手术中，甲状旁腺的意外切除或损伤导致了超过 80%的慢性甲状旁腺功能减退症（HypoPT）病例。本研究旨在探讨甲状腺癌患者行甲状腺全切除术和中央区淋巴结清扫术后发生永久性 HypoPT 的相关因素。
共有 103 例患者经筛选符合研究标准，其中 89 例患者进行了为期一年的前瞻性观察。对所有患者的人口统计学和手术相关因素以及术前和术后的矿物质稳态生化参数进行了统计学分析。术后低钙血症（血清钙浓度<2.25mmol/L）而非甲状旁腺素（PTH）浓度降低被认为是 HypoPT 的诊断标准。
术后第 1 天（POD1），29 例患者的 PTH 血清浓度降至正常范围以下（<12pg/mL），19 例患者的 PTH 检测不到（<6pg/mL）。术后 1 年，12 例 POD1 PTH 检测不到的患者出现低钙血症，需要接受治疗，被诊断为永久性 HypoPT。其余患者均恢复正常血钙水平。POD1 PTH 检测不到的患者发生永久性 HypoPT 的相对风险为 88.75。POD1 血清钙浓度中位数在 POD1 PTH 检测不到的患者和 POD1 PTH 检测到的患者之间存在显著差异（p<0.001）。在 POD1 PTH 检测不到的亚组中，永久性或暂时性 HypoPT 患者的 POD1 血清钙差异无统计学意义（中位数，1.82mmol/L 比 1.96mmol/L）。术后 1 个月，永久性 HypoPT 患者的血清钙水平低于其他所有患者（p=0.167）。术后 1 年，12 例永久性 HypoPT 患者中有 10 例的 PTH 血清浓度在正常范围内，但明显低于术前，明显低于血钙恢复正常的患者。甲状旁腺的切除或移植数量并不影响永久性 HypoPT 的发生。
POD1 PTH 检测不到是永久性 HypoPT 的重要危险因素。永久性 HypoPT 的主要原因是左侧原位甲状旁腺的不可逆损伤。
