肾转移性多形性腺瘤临床病理观察

Clinincopathologic characteristics of metastasizing pleomorphic adenoma in kidney

目的探讨肾转移性多形性腺瘤的临床病理特征、发病及转移机制、免疫表型及诊断与鉴别诊断。方法对1例肾转移性多形性腺瘤的临床表现、大体及组织学特征、免疫组化等进行观察,并复习文献。结果患者男性,70岁。体检发现右肾肿瘤10天,行腹腔镜下右肾根治性切除术。大体为一个位于右肾下极界限清楚的实性肿物,灰白色,分叶状。镜下肿瘤呈典型的涎腺多形性腺瘤的形态学特征,结构呈多形性,肿瘤性上皮和间质混合存在,上皮和肌上皮成团及片状埋于软骨黏液样基质中,并散在分布成熟的鳞状上皮细胞巢。免疫组化示肿瘤细胞CKpan、vimentin、p16和β-catenin(+),calponin、CD10和S-100部分(+),p63弱(+),CK14(-)。结论肾转移性多形性腺瘤是一种罕见的恶性肿瘤,诊断需要有明确的病史,并且需与多形性腺瘤中的癌、癌肉瘤及肾黏液样小管状和梭形细胞癌等鉴别。

Objective To explore the clinicopathological characteristics of metastasizing pleomorphic adenoma in the kidney. Methods A case of metastasizing pleomorphic adenoma in kidney was studied with histology and immunohistochemical staining, and its clinical and pathological findings were further analyzed with review of the literature. Results The patient was a 70-year-old man who had a renal mass during his annual physical examination. Grossly, the cut surface of the kidney revealed a grey-white, solid, lobulated, well-circumscribed tumor in the parenchyma. Microscopically, the tumour had similar appearance to that of pleomorphie adenoma of the parotid gland and the microscopic features of the tumor showed a mixed cell composition with mesenchymal elements demonstrating chondroid differentiation embedded in a myxoid matrix, as well as epithelial components consisting of ductal structures and squamous cell nests without atypia. Immunohistochemical studies showed that the epithelial component stained positive for Pan-CK, vimentin, p16, and 13-catenin, with partial expression of the myoepithelial markers p63, S-100, calponin, and CD10, but negative for CK14. Conclusions Metastasizing pleomorphic adenoma in kidney is rare malignant neoplasm, and needs to be distinguished from carcinoma ex pleomorphic adenoma, carcinosarcoma and mueinous tubular spindle cell carcinoma.