Ilori Evelyn O, Hamdan Hanan, Sarode Venetia, Hussain Iram, Islam Ana, Bishop Justin A
Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390, USA.
Propath, Dallas, TX, USA.
Diagn Pathol. 2025 Jul 29;20(1):88. doi: 10.1186/s13000-025-01682-7.
Spindle epithelial tumor with thymus-like differentiation or elements (SETTLE) is a rare and malignant biphasic tumor of the thyroid that has proven challenging to diagnose by cytology.
A 20-year-old-male presented with a large left neck nodule and neck tightness. Laboratory tests were normal. Computed Tomography (CT) of the neck revealed a thyroid mass involving the isthmus and entire left lobe. Ultrasound-guided fine needle aspiration of the mass demonstrated sheets and clusters of oval to spindle cells with associated fibrovascular cores. The cells had moderately pleomorphic nuclei with stippled chromatin, inconspicuous nucleoli, and minimal cytoplasm, and a diagnosis of medullary thyroid carcinoma was made. A total thyroidectomy and neck dissection was performed. Morphological and immunohistochemical evaluation of the specimen resulted in a diagnosis of SETTLE with angioinvasion and involved lymph nodes.
SETTLE has several mimics cytologically, such as medullary thyroid carcinoma, that makes accurate pre-operative diagnosis challenging. We present a review of cytology information from literature, highlighting features that differentiates SETTLE from its mimics.
伴有胸腺样分化或成分的梭形上皮肿瘤（SETTLE）是一种罕见的甲状腺恶性双相肿瘤，经细胞学诊断颇具挑战性。
一名20岁男性，出现左侧颈部大肿块及颈部紧绷感。实验室检查正常。颈部计算机断层扫描（CT）显示甲状腺肿物累及峡部及整个左叶。超声引导下对肿物进行细针穿刺，可见成片及成簇的椭圆形至梭形细胞，伴有相关纤维血管轴心。细胞具有中度多形性核，染色质呈点彩状，核仁不明显，胞质极少，诊断为甲状腺髓样癌。遂行甲状腺全切术及颈部淋巴结清扫术。对标本进行形态学和免疫组化评估后，诊断为伴有血管侵犯及淋巴结受累的SETTLE。
SETTLE在细胞学上有多种相似病变，如甲状腺髓样癌，这使得术前准确诊断具有挑战性。我们对文献中的细胞学信息进行了综述，强调了SETTLE与其相似病变的鉴别特征。
