血清降钙素在甲状腺髓样癌全程管理中意义与应用

Significance and application of serum calcitonin measurement in the diagnosis and management of medullary thyroid cancer

降钙素(Ctn)是一种参与骨钙代谢的多肽类激素,主要由甲状腺滤泡旁细胞分泌。甲状腺髓样癌(MTC)起源于甲状腺滤泡旁细胞,可大量分泌Ctn。Ctn是MTC最敏感的血清学标记物之一,对于MTC的诊断、术前和术后的评估和管理均有重要意义:(1)对甲状腺结节病人进行Ctn筛查可早期诊断MTC,有助于改善预后。(2)术前Ctn水平与肿瘤恶性程度有关,可辅助决定手术范围。(3)术后随访中监测Ctn可用于预测复发风险,早期发现并处理转移病灶。随着对MTC认识的增加和检测技术的改善,Ctn在各国相关临床指南中的地位也逐渐提升。然而,目前Ctn的检测仍缺乏明确的截断值,Ctn检测的假阳性率较高,并且尚缺乏Ctn筛查的卫生经济学获益证据。对细针穿刺针洗脱液进行Ctn检测可一定程度上提升诊断的准确率,有望成为新的临床切入点。相信通过未来更多研究,Ctn检测在MTC全程管理中的应用框架将日益完善。

Calcitonin is a peptide hormone regulating the homeostasis of calcium metabolism.lt is mainly secreted by parafollicular cells(also known as C cells)of the thyroid gland.Medullary thyroid cancer(MTC)originates from parafollicular cells,generally characterized by excess secretion of calcitonin.As one of the most sensitive biomarkers of MTC,serum calcitonin is of great significance to the diagnosis,evaluation and follow-up of MTC:(1)Screening of serum calcitonin in patients with thyroid nodules may diagnose and manage MTC in early stage,leading to a better prognosis;(2)The level of serum calcitonin preoperatively is associated with the aggressiveness of MTC and may help determine the extent of operation;(3)Early detection of tumor recurrence would be achieved by monitoring the level of calcitonin postoperatively.With the increasing knowledge about MTC and advancement in detection assays,the measurement of calcitonin plays an emerging role in the management guidelines of MTC.Nonetheless,controversies remain regarding the cut-off value of serum calcitonin,its high false positive rate and the costeffectiveness evidence of calcitonin screening.Calcitonin measurement in wash-out fluid from fine-needle aspiration of thyroid nodules may increase the accuracy of diagnosis.Further progress in the application of calcitonin testing to manage MTC will be made with more relevant studies in the future.