Finley J L, Silverman J F, Strausbauch P H, Dabbs D J, West R L, Weaver M D, Norris H T
Diagn Cytopathol. 1986 Apr-Jun;2(2):118-25. doi: 10.1002/dc.2840020205.
Two cases of malignant thymic neoplasms diagnosed by transthoracic fine-needle aspiration (FNA) biopsy under fluoroscopic and computerized axial tomography (CT) guidance with histologic, immunocytochemical, and ultrastructural confirmation are presented. The clinical and cytomorphologic features of the first case were typical of a malignant thymoma. A characteristic biphasic cell population of benign epithelial cells and mature lymphocytes was seen in Diff-Quik- and Papanicolaou-stained smears from the anterior mediastinal mass and the paravertebral metastasis and was confirmed by histologic examination. Immunoperoxidase studies for T and B cell subsets demonstrated lymphocytes with the thymic lymphocyte phenotype (Leu 6). Electron microscopic (EM) examination revealed epithelial cells with desmosomal attachments, tonofilaments, and extended cell processes along with mature lymphocytes. FNA biopsy of the second case demonstrated features of a thymic carcinoma. Individually scattered and loosely clustered small groups of markedly anaplastic and pleomorphic large cells were seen both in the Diff-Quik- and Papanicolaou-stained smears. EM performed on the FNA specimen demonstrated the poorly differentiated epithelial nature of the malignancy. The mediastinal mass was partially resected and demonstrated an undifferentiated carcinoma staining positively for low-molecular-weight cytokeratin. Ultrastructure demonstrated cell attachments and relationships consistent with carcinoma. The lack of a lung or other extrapulmonary primary tumor was consistent with a thymic carcinoma. These cases demonstrate the value of performing EM and immunocytochemistry on material obtained by fine-needle aspiration, which can aid in establishing the correct diagnosis and facilitate the clinical management of patients with malignant thymic neoplasms.
本文介绍了两例经荧光镜和计算机断层扫描（CT）引导下经胸细针穿刺（FNA）活检诊断的恶性胸腺肿瘤，并经组织学、免疫细胞化学和超微结构证实。第一例的临床和细胞形态学特征典型为恶性胸腺瘤。在前纵隔肿块和椎旁转移灶的Diff-Quik和巴氏染色涂片中可见良性上皮细胞和成熟淋巴细胞组成的特征性双相细胞群，并经组织学检查证实。T和B细胞亚群的免疫过氧化物酶研究显示淋巴细胞具有胸腺淋巴细胞表型（Leu 6）。电子显微镜（EM）检查显示上皮细胞有桥粒连接、张力丝和延长的细胞突起以及成熟淋巴细胞。第二例的FNA活检显示为胸腺癌特征。在Diff-Quik和巴氏染色涂片中均可见单个散在和松散聚集的小群明显间变和多形性大细胞。对FNA标本进行的EM显示恶性肿瘤的上皮分化不良。纵隔肿块部分切除，显示为低分子量细胞角蛋白染色阳性的未分化癌。超微结构显示细胞连接和关系符合癌的特征。缺乏肺或其他肺外原发性肿瘤符合胸腺癌。这些病例证明了对细针穿刺获得的材料进行EM和免疫细胞化学检查的价值，这有助于确立正确诊断并促进恶性胸腺肿瘤患者的临床管理。
