Ahmed Omar I, Salih Ziyan T
Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina.
Diagn Cytopathol. 2017 Sep;45(9):851-856. doi: 10.1002/dc.23748. Epub 2017 May 22.
Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Simultaneous involvement of the thyroid gland by multiple malignancies, is a rare occurrence. Similarly, primary thyroid lymphomas are also rare. We are reporting a rare case of a dual thyroid malignancy; PTC with secondary thyroid involvement by chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diagnosed on cytology and confirmed with flow cytometry, histology and immunohistochemistry. Imaging showed two hypermetabolic nodules, one in left parotid gland, and the other in the thyroid isthmus. Cytology smears showed features of PTC along with an atypical lymphocytic infiltrate, which co-expressed CD5, CD19, and CD23 on flowcytometry analysis. Subsequent thyroidectomy showed the atypical lymphocytic infiltrate involving the PTC papillae themselves. The diagnosis of dual malignancies on thyroid FNA is extremely rare and often unexpected, but is possible using appropriate ancillary studies.
乳头状甲状腺癌（PTC）是最常见的甲状腺恶性肿瘤。甲状腺同时被多种恶性肿瘤累及的情况很少见。同样，原发性甲状腺淋巴瘤也很罕见。我们报告一例罕见的双重甲状腺恶性肿瘤病例；PTC合并慢性淋巴细胞白血病/小淋巴细胞淋巴瘤（CLL/SLL）继发性甲状腺受累，通过细胞学诊断，并经流式细胞术、组织学和免疫组织化学证实。影像学检查显示两个代谢活跃的结节，一个位于左侧腮腺，另一个位于甲状腺峡部。细胞学涂片显示PTC特征以及非典型淋巴细胞浸润，流式细胞术分析显示其共表达CD5、CD19和CD23。随后的甲状腺切除术显示非典型淋巴细胞浸润累及PTC乳头本身。通过甲状腺细针穿刺活检（FNA）诊断双重恶性肿瘤极为罕见且常常出乎意料，但使用适当的辅助检查是有可能的。
