Abstract：
BACKGROUND: A basal serum calcitonin (Ct) increase >100 pg/mL in patients with a thyroid nodule is consistent with the diagnosis of medullary thyroid cancer (MTC). In cases where the CT test have a slight to moderate increase, the calcium gluconate stimulation test is helpful to increase diagnostic accuracy. However, reliable cut-offs for calcium-stimulated Ct are still lacking. The aim of this study was to evaluate the sex-specific calcium-stimulated Ct cutoffs for the diagnosis of MTC in a multicenter series. A comparison between different Ct assays has been also performed.
METHODS: 90 subjects undergone calcium-stimulated Ct for a suspected MTC in 5 Endocrine Units between 2010-2021 were retrospectively analyzed. Serum Ct concentrations were assessed by immunoradiometric (IRMA) or chemiluminescence (CLIA) assays.
RESULTS: MTC was diagnosed in 37 (41.1%) and excluded in 53 (58.9%) patients. The best calcium-stimulated Ct cut-off to identify MTC was 611 pg/mL in males (AUC =0.90, 95% CI (0.76;1) and 445 pg/mL in females (AUC=0.79, 95% CI (0.66;0.91). Logistic regression analysis showed that both basal (OR 1.01, P=0.003) and peak Ct after stimulation (OR 1.07, P=0.007) were significantly associated with MTC, together with sex (OR=0.06, P<0.001). The \"Ct assay\" variable was also considered in the logistic regression model, but it was not significantly associated with MTC (OR=0.93, P=0.919).
CONCLUSIONS: This study indicates that calcium test could be helpful to identify patients with early-stage MTC and those without MTC. A Ct value of 611 pg/mL in males and 445 pg/mL in females are proposed as the optimal Ct cut-offs at the stimulation test.
METHODS: 90 subjects undergone calcium-stimulated Ct for a suspected MTC in 5 Endocrine Units between 2010-2021 were retrospectively analyzed. Serum Ct concentrations were assessed by immunoradiometric (IRMA) or chemiluminescence (CLIA) assays.
RESULTS: MTC was diagnosed in 37 (41.1%) and excluded in 53 (58.9%) patients. The best calcium-stimulated Ct cut-off to identify MTC was 611 pg/mL in males (AUC =0.90, 95% CI (0.76;1) and 445 pg/mL in females (AUC=0.79, 95% CI (0.66;0.91). Logistic regression analysis showed that both basal (OR 1.01, P=0.003) and peak Ct after stimulation (OR 1.07, P=0.007) were significantly associated with MTC, together with sex (OR=0.06, P<0.001). The \"Ct assay\" variable was also considered in the logistic regression model, but it was not significantly associated with MTC (OR=0.93, P=0.919).
CONCLUSIONS: This study indicates that calcium test could be helpful to identify patients with early-stage MTC and those without MTC. A Ct value of 611 pg/mL in males and 445 pg/mL in females are proposed as the optimal Ct cut-offs at the stimulation test.
摘要：
背景：甲状腺结节患者的基础血清降钙素（Ct）增加>100pg/mL与甲状腺髓样癌（MTC）的诊断一致。在CT检查有轻微到中度增加的情况下，葡萄糖酸钙刺激试验有助于提高诊断准确性。然而,仍然缺乏可靠的钙刺激的Ct截止值。这项研究的目的是在多中心系列中评估性别特异性钙刺激的Ct截止值，以诊断MTC。还进行了不同Ct测定之间的比较。
方法：对2010-2021年期间在5个内分泌单位中接受钙刺激的Ct疑似MTC患者进行回顾性分析。通过免疫放射(IRMA)或化学发光(CLIA)测定评估血清Ct浓度。
结果：在37例（41.1%）患者中诊断出MTC，在53例（58.9%）患者中排除MTC。识别MTC的最佳钙刺激Ct截止值为男性611pg/mL（AUC=0.90，95％CI（0.76;1）和女性445pg/mL（AUC=0.79，95％CI（0.66;0.91）。Logistic回归分析显示，刺激后基础（OR1.01，P=0.003）和峰值Ct（OR1.07，P=0.007）均与MTC显著相关。性别(OR=0.06,P<0.001)。在逻辑回归模型中也考虑了“Ct测定”变量，但与MTC无显著相关性(OR=0.93,P=0.919)。
结论：本研究表明，钙检测有助于识别早期MTC患者和无MTC患者。建议将雄性的Ct值为611pg/mL，雌性为445pg/mL，作为刺激测试中的最佳Ct截止值。
方法：对2010-2021年期间在5个内分泌单位中接受钙刺激的Ct疑似MTC患者进行回顾性分析。通过免疫放射(IRMA)或化学发光(CLIA)测定评估血清Ct浓度。
结果：在37例（41.1%）患者中诊断出MTC，在53例（58.9%）患者中排除MTC。识别MTC的最佳钙刺激Ct截止值为男性611pg/mL（AUC=0.90，95％CI（0.76;1）和女性445pg/mL（AUC=0.79，95％CI（0.66;0.91）。Logistic回归分析显示，刺激后基础（OR1.01，P=0.003）和峰值Ct（OR1.07，P=0.007）均与MTC显著相关。性别(OR=0.06,P<0.001)。在逻辑回归模型中也考虑了“Ct测定”变量，但与MTC无显著相关性(OR=0.93,P=0.919)。
结论：本研究表明，钙检测有助于识别早期MTC患者和无MTC患者。建议将雄性的Ct值为611pg/mL，雌性为445pg/mL，作为刺激测试中的最佳Ct截止值。
