Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Department of Pathology, Catholic University-Fondazione Policlinico Universitario, Rome, Italy.
Cancer Cytopathol. 2021 Jun;129(6):439-449. doi: 10.1002/cncy.22390. Epub 2020 Nov 24.
Thyroid paragangliomas are extremely rare and often are misdiagnosed by preoperative fine-needle aspiration (FNA) because their cytologic features overlap with those of other thyroid neoplasms. The objective of this study was to review the cytomorphology in a series of thyroid paragangliomas and correlate the findings with histopathology.
Five thyroid paraganglioma cases that underwent FNA were reviewed. Their clinical presentation, radiology features, cytomorphology, ancillary tests, and histopathology were analyzed.
All patients were women with an average age of 49 years (age range, 35-61 years) and presented with an asymptomatic, solitary thyroid nodule. Radiologically, these nodules (size range, 1.8-3.0 cm) were well circumscribed, hypoechoic, and hypervascular. FNA smears showed clusters of loosely cohesive, medium-to-large epithelioid cells with clear-to-eosinophilic and occasionally foamy cytoplasm that had indistinct cytoplasmic borders. The nuclei were round to oval with focal nuclear membrane irregularities, inconspicuous nucleoli, focal marked anisonucleosis, and occasional intranuclear pseudoinclusions. Naked nuclei, variable numbers of plasmacytoid cells, multinucleated giant cells, and sustentacular cells were present in the background along with blood vessels and lymphocytes. Cytology diagnoses were incorrect and included follicular neoplasm (n = 4) and follicular lesion of undetermined significance (n = 1). Final histopathology with immunohistochemistry revealed conventional paraganglioma (n = 3) or sclerosing paraganglioma with invasive features (n = 2).
All thyroid paragangliomas were misdiagnosed on FNA as follicular neoplasms, in part because of the rarity of these tumors in this location and cytomorphology mimicking follicles. The absence of colloid, the presence of naked nuclei, focal marked anisonucleosis, and the presence of sustentacular cells are important cytology clues.
甲状腺副神经节瘤极为罕见，术前细针抽吸（FNA）常误诊，因为其细胞学特征与其他甲状腺肿瘤重叠。本研究的目的是回顾一系列甲状腺副神经节瘤的细胞学形态，并将其与组织病理学相关联。
回顾了 5 例接受 FNA 的甲状腺副神经节瘤病例。分析了其临床表现、影像学特征、细胞学形态、辅助检查和组织病理学特征。
所有患者均为女性，平均年龄 49 岁（年龄范围 35-61 岁），表现为无症状的单发甲状腺结节。影像学上，这些结节（大小范围 1.8-3.0cm）边界清晰，呈低回声，富含血管。FNA 涂片显示松散聚集的中等至大上皮样细胞簇，具有透明至嗜酸性，偶尔呈泡沫状细胞质，细胞质边界不明显。细胞核呈圆形至椭圆形，核膜不规则，核仁不明显，局灶性显著异形核，偶尔有空泡核内包涵体。背景中存在裸核、不同数量的浆细胞样细胞、多核巨细胞和支持细胞，以及血管和淋巴细胞。细胞学诊断不正确，包括滤泡性肿瘤（n=4）和滤泡性病变意义未明（n=1）。最终的组织病理学和免疫组化显示，常规副神经节瘤（n=3）或具有侵袭性特征的硬化性副神经节瘤（n=2）。
所有甲状腺副神经节瘤在 FNA 上均误诊为滤泡性肿瘤，部分原因是这些肿瘤在该部位罕见且细胞学形态类似于滤泡。缺乏胶体、裸核、局灶性显著异形核和支持细胞的存在是重要的细胞学线索。
