Caecal adenocarcinoma with rhabdoid phenotype: An immunohistochemical and ultrastructural analysis
Caecal adenocarcinoma with rhabdoid phenotype: An immunohistochemical and ultrastructural analysis
复制标题
具有横纹肌样表型的盲肠腺癌：免疫组织化学和超微结构分析
作者：
R. Chetty;P. Bhathal
显微镜下发现一例72岁女性盲肠息肉样腺癌，主要由横纹肌样细胞组成。肝脏和淋巴结中的沉积物与原发肿瘤的组织学形态相似。横纹肌样细胞具有丰富的嗜酸性细胞质、偏心的核和突出的核仁。鉴别诊断包括横纹肌肉瘤、化生癌(伴肉瘤样去分化癌)、癌肉瘤和肾外横纹肌样瘤。横纹肌样细胞与细胞角蛋白、上皮膜抗原和波形蛋白呈强阳性反应。在超微结构上，观察到中间丝的细胞质轮生。多个切片、免疫组织化学和超微结构检查均显示与横纹肌样区域混合的腺癌成分。在一个区域，恶性腺体内有横纹肌样细胞。这个病例说明，许多肿瘤的横纹肌样外观可能具有误导性，只是肾外部位的一种非特异性的形态表型模式。在肾外环境中，应仔细寻找鉴别的证据。
A polypoid caecal adenocarcinoma in a 72-year-old female was found microscopically to be composed mainly of rhabdoid cells. Deposits in the liver and lymph nodes had a similar histological appearance to the primary tumour. The rhabdoid cells were typified by abundant eosinophilic cytoplasm, eccentric nuclei and prominent nucleoli. The differential diagnosis included rhabdomyosarcoma, metaplastic carcinoma (carcinoma with sarcomatoid dedifferentiation), carcinosarcoma and extra-renal rhabdoid tumour. The rhabdoid cells showed strong immunoreactivity with cytokeratin, epithelial membrane antigen and vimentin. Ultrastructurally, cytoplasmic whorls of intermediate filaments were noted. Multiple sections, immunohistochemistry and ultrastructural examination all revealed an adenocarcinomatous component which blended with the rhabdoid areas. In one area a rhabdoid cell was present within a malignant gland. This case illustrates that the rhabdoid appearance of many tumours can be misleading and is merely a non-specific morpho-phenotypic pattern seen in extra-renal sites. In the extra-renal setting, careful search for evidence of differentiation should be undertaken.