伴淋巴结鳞状细胞癌转移的梭形细胞肌上皮癌临床病理分析

Clinicopathologic Analysis of Spindle Cell Myoepithelial Carcinoma Associated with Lymph Node Squamous Cell Carcinoma Metastasis

目的探讨伴淋巴结鳞状细胞癌转移的梭形细胞肌上皮癌病理特征、诊断和鉴别诊断,提高对该肿瘤的诊断水平。方法对1例颌下腺梭形细胞肌上皮癌及颈清扫淋巴结进行组织形态学和免疫组化观察,并结合文献复习。结果肿瘤主要由梭形细胞构成,细胞排列紧密,异型性明显,分裂相易见伴大片坏死及玻璃样变。经广泛取材,见到少许小管样结构及小灶状鳞状细胞癌成分。颈清扫淋巴结可见鳞状细胞癌转移。免疫组化显示,梭形肿瘤细胞:SMA、Desmin灶状阳性,p53强阳性,CK(AE1/AE3)、S-100、CD34、GFAP、CD10、HMB45均为阴性;淋巴结转移癌成分CK(AE1/AE3)阳性、SMA阴性。结论肌上皮癌属于罕见的恶性肿瘤,梭形细胞为主的肌上皮癌,其淋巴结转移癌的形态可以与肿瘤主体细胞的形态截然不同。根据组织学特点,结合免疫组化及电镜观察,可以作出明确诊断及鉴别诊断。

Objective To explore the clinical pathological features,diagnosis and differential diagnosis of spindle cell myoepithelial carcinoma with lymph node squamous cell carcinoma metastasis. Methods A case of spindle cell myoepithelial carcinoma of the submaxillary salivary gland with radical neck dissection was examined with light microsecopy and immunohistochemistry, and related literatures were reviewed. Results Microscopically, the tumor was composed of spindle-shaped cells and the cells were obviously atypical. Mitoses were seen usually with pellet necrosis and hyaline degeneration. Focal areas showed the ductile structure and the squamous cell carcinoma element. Metastatic squamous cell carcinoma（1/4） was seen in the lymph nodes of radical neck dissection. Immunohistochemically,the spindle tumor cells were strong positive for p53, partially positive for SMA and desmin, and negative for CK （AE1/AE3）, S-100 protein, CD34, GFAP, CD10, and HMB45. Conclusion The myoepithelial carcinoma is a very rare malignant tumor. The spindle cell myoepithelial carcinoma may me- tastasize to lymph nodes,and its morphology is different from the primary tumor. The definite diagnosis should be based on the histopathological, immunohistochemical and electron microscope features.