食管基底细胞样鳞状细胞癌—光镜、电镜和免疫组化研究

Basaloid Squamous Carcinoma of the Esophagus-Immunohistochemical,Light and Electron Microscopic

目的观察食管基底细胞样鳞状细胞癌(basaloid-squamous carcinoma,BSC)的组织学形态特征,探讨其诊断及鉴别诊断。方法对15例BSC标本进行光镜、电镜及免疫组织化学研究。结果BSC组织学有许多与涎腺腺样囊性癌(adenoid cystic carcinoma,ACC)相似的特征。但BSC癌细胞分化较低异型性较强,癌巢周围细胞呈栅栏状排列,肿瘤表面鳞状上皮常伴发原位癌或浅表浸润性鳞状细胞癌;偶见癌巢与表面鳞状上皮基底层相连、或偶见癌巢内形成鳞状细胞,或腺管样结构,这些与ACC不同。超微结构与ACC相似,但癌细胞分化更低,胞质内可见张力原纤维是与ACC不同之处。免疫组化结果:基底细胞样成分:CK(pan)15/15、EMA15/15、CEA6/15、S-100 6/15、SMA7/15阳性,显示肿瘤含有上皮和肌上皮细胞。结论BSC是一种分化较低、侵袭性较强,有向腺样、鳞状及肌上皮细胞分化倾向,具有独特临床病理特征的恶性肿瘤,其组织学特征可作为病理诊断标准,超微结构及免疫组织化学特征可辅助鉴别诊断。

Objective To observe the histological features of basoloid-squamous carcinoma and further explore its diagnosis and differentiated diagnosis. Methods Immunohistochemical, light and electron microscopic methods were used to study 15 cases of BSC. Results BSC had many similar histological features to adenoid cystic carcinoma. But cancer cells of BSC have lesser degree of differentiation and higher pleomorphisrn. The cells at the edge of the basaloid islands tended to show palisading arrangement. Squamous epithelium on the surface of tumor often accompanied with carcinoma in situ or superficial invasive squamous cell carcinoma. Occasionally cancer nets were connected with basement layer of squamous epithelium laying in the surface, and rare squamous cells or gland-like structures were seen in the cancer nests. These were different to ACC. The ultra structure for cancer cells of BCC had lower differentiation and tonofibril was seen in the cytoplasm. A panel of immunostains were used and the results： for basaloid component positive： CK （pan） 15/15, EMA 15/15, CEA 6/ 15,S-100 6/15,SMA 7/15, showed there were epithelial and myoepithelial cells in the tumor. Conclusion BSC is a kind of low differentiation and high invasive malignancy tumor which has unique clinicopathological features. It has tendency to differentiate to adenoid, squamous and myoepithelial cells. The histological features can serve as criterion of pathological diagnose. And the ultra structure and immunohistochemical features are helpful to differentiated diagnoses.