同步性甲状腺髓样癌与乳头状癌伴混合成分侧颈淋巴结转移：一例病例报告

文献信息

中文摘要

背景： 同步性甲状腺髓样癌（MTC）与甲状腺乳头状癌（PTC）是不常见的甲状腺恶性肿瘤，而同一转移灶内同时含有两种肿瘤成分的混合成分颈部淋巴结转移则极为罕见。本病例强调了整合不一致的特定部位细针穿刺（FNA）结果与血清生物标志物对于术前识别这种不寻常表现的重要诊断价值。
病例描述： 一名65岁男性因右侧颈部肿块进行性增大并伴同侧颈部淋巴结肿大超过两个月就诊。超声检查显示一个4.28 cm × 2.28 cm × 2.54 cm的甲状腺影像报告和数据系统（TI-RADS）5类甲状腺结节，并伴有多个右侧颈部肿大淋巴结。血清降钙素（Ctn）（1,796.38 ng/L）、癌胚抗原（CEA）（81.69 μg/L）和甲状腺球蛋白（Tg）（163.65 μg/L）水平显著升高。甲状腺结节FNA支持MTC，而转移性颈部淋巴结FNA显示PTC，提供了不一致的细胞学证据，从而在术前提高了对同步性甲状腺恶性肿瘤的怀疑。全甲状腺切除术联合双侧颈淋巴结清扫术发现多灶性MTC和对侧微小PTC，并伴有累及10个颈部淋巴结的混合成分转移。术后未发生喉返神经损伤或永久性甲状旁腺功能减退等并发症。血清甲状旁腺激素（PTH）水平在12个月时恢复至40.85 ng/L。血清Ctn、CEA和Tg水平持续保持低位（分别为57.29 ng/L、3.96 μg/L和0.39 μg/L），且12个月内的随访颈部CT扫描未见淋巴结肿大迹象。
结论： 本病例表明，原发甲状腺病变与转移淋巴结之间不一致的FNA结果，伴随双标志物升高（Ctn、CEA和Tg），强烈提示同步性MTC和PTC。全面的根治性手术方法和严格的双生物标志物纵向监测是实现最佳肿瘤学控制和防止诊断遗漏的关键。

英文摘要

BACKGROUND: Synchronous medullary thyroid carcinoma (MTC) and papillary thyroid carcinoma (PTC) are uncommon thyroid malignancies, whereas mixed-component cervical lymph node metastases containing both tumor components within the same metastatic deposit are exceptionally rare. This case highlights the diagnostic value of integrating discordant site-specific fine-needle aspiration (FNA) findings with serum biomarkers for preoperative recognition of this unusual presentation.
CASE DESCRIPTION: A 65-year-old man presented with a progressively enlarging right-sided neck mass accompanied by ipsilateral cervical lymphadenopathy for more than two months. Ultrasonography demonstrated a 4.28 cm × 2.28 cm × 2.54 cm Thyroid Imaging Reporting and Data System (TI-RADS) 5 thyroid nodule with multiple enlarged right cervical lymph nodes. Serum calcitonin (Ctn) (1,796.38 ng/L), carcinoembryonic antigen (CEA) (81.69 μg/L), and thyroglobulin (Tg) (163.65 μg/L) levels were markedly elevated. FNA of the thyroid nodule supported MTC, whereas FNA of a metastatic cervical lymph node demonstrated PTC, providing discordant cytological evidence that raised preoperative suspicion of synchronous thyroid malignancies. Total thyroidectomy with bilateral neck dissection revealed multifocal MTC and microscopic contralateral PTC with mixed-component metastases involving 10 cervical lymph nodes. No postoperative complications such as recurrent laryngeal nerve injury or permanent hypoparathyroidism occurred. Serum parathyroid hormone (PTH) levels recovered to 40.85 ng/L at 12 months. Serum Ctn, CEA, and Tg levels remained persistently low (57.29 ng/L, 3.96 μg/L, and 0.39 μg/L, respectively), and follow-up neck CT scans over the 12 months showed no signs of lymphadenopathy.
CONCLUSIONS: This case demonstrates that discordant FNA results between primary thyroid lesions and metastatic lymph nodes, accompanied by dual-marker elevation (Ctn, CEA and Tg), strongly indicate synchronous MTC and PTC. A comprehensive radical surgical approach and rigorous dual-biomarker longitudinal surveillance are key to achieving optimal oncological control and preventing diagnostic omissions.