甲状腺间叶性软骨肉瘤临床病理观察

Mesenchymal chondrosarcoma of thyroid:a clinicopathologic study

目的探讨甲状腺间叶性软骨肉瘤(MC)的临床病理学特征、免疫表型、诊断以及鉴别诊断。方法分析1例甲状腺MC的临床特征、组织学形态、免疫表型及特殊染色结果,并复习相关文献。结果患者男性,33岁。以颈部无痛性肿块半年就诊。肿瘤位于甲状腺被膜内,似有完整包膜;切面灰白、灰黄色相间,有光泽,中央可见点、片状钙化、骨化,质硬。镜下肿瘤由未分化小细胞及分化较好岛状软骨细胞交织而成,小细胞区细胞丰富,由圆形、短梭形细胞组成,可见核分裂象;富于血管,可见血管外皮瘤样结构;软骨细胞多分化较好,细胞核有异型,可见钙化、骨化。免疫组化:小细胞CD99(+)、部分Leu-7和vimentin(+),而S-100、TG、AE1/AE3、FⅧRag、LCA、NSE、Syn、CgA、GFAP、NF和CD117均(-);软骨细胞S-100、NSE、GFAP和FⅧRag(+)。术后无复发和转移。结论甲状腺MC极其罕见,具有典型的病理组织学特征,需与伴有软骨化生的甲状腺未分化癌、非典型腺瘤及有软骨成分的癌肉瘤鉴别。预后可能有别于其他部位MC,尚需进一步随访。

Objective To study the clinicopathological features, immunophenotype and differential diagnosis of mesenchymal chondrosarcoma （MC） of the thyroid. Methods Clinical, radiological and pathological features of this MC of thyroid were analyzed along with a literature review. Results The patient was male of 33 years old, and presented with indolent lump. Grossly, the lesion located under the fibrous capsule of thyroid gland and had a seemingly complete peplos, cut surface of the tumor appeared as the overlapped gray and yellow, with luster. Ossification appeared in the center of the cut surface. Histologically, the tumor was composed of undifferentiated small cell and well-differentiated chondrocyte. In the area of small cell, cell was abundant, round and short spindle, mitotic figure was not scanty, vessels were affluent and showed the bimorphic pattern and haemangiopericytoma-like areas typical of MC. In the area of chondrocyte, the cells were well-differentiated, nuclear atypia and ossification was presented. [mmunohistochemica/fy, the small cells were positive for CD99, incompletely positive for Leu-7 and vimentin, negative for S-100, TG, AE1/AE3, F＇V^Rag, LCA, NSE, Syn, CgA, GFAP, NF, and CDll7. The chondrocytes were positive for S-100, NSE, GFAP, and FVIRag. The patient was alive without evidence of recurrence or matastasis. Conclusion Primary MC of thyroid is rare and has typical histological features, and the differential diagnosis should be made among undifferentiated carcinoma of thyroid coexistent with chondrometaplasia, atypical adenoma and c with part cartilage