Zafar N, Spencer D, Berry A D
Department of Pathology, University of Tennessee, Memphis 38163, USA.
Diagn Cytopathol. 1997 Jan;16(1):42-6. doi: 10.1002/(sici)1097-0339(199701)16:1<42::aid-dc10>3.0.co;2-b.
Embryonal (metanephric) adenoma of the kidney, like Wilms' tumor, exhibits small monomorphic, blue cells arranged as vague, tubular rosettes. Unlike Wilms' tumor, which requires chemotherapy or multi-modality therapy for optimal management, the available evidence indicates that embryonal adenoma is most likely cured by simple enucleation or nephrectomy. Two women, age 54 (Case 1) and 78 (Case 2), respectively, underwent needle biopsy for a radiologically well circumscribed renal lesion with associated hematuria. The cellular smears contained vague rosette-like arrangement of small, blue cells with scant cytoplasm and evenly distributed, fine, nuclear chromatin. In cell blocks, these cells were arranged as compact, primitive, tubular rosettes or rare, moresolid clusters. Assuming that the absence of undifferentiated blastema and primitive glomeruli represented a sampling error, a diagnosis suggesting of Wilms' tumor was made in Case 1. At nephrectomy, despite extensive sampling, the typical triphasic Wilms' morphology and anaplastic or necrotic areas were not seen. In the presence of architectural monotony, the diagnosis in Case 1 was amended to embryonal adenoma. Case 2 was cytologically diagnosed as embryonal adenoma of the kidney and is being followed conservatively. In our opinion, the presence of monotypic architecture at cytology/histology is very helpful in differentiating renal embryonal (metanephric) adenoma from Wilms' tumor.
肾胚胎性（后肾）腺瘤与肾母细胞瘤一样，表现为小的单形性蓝色细胞，呈模糊的管状玫瑰花结样排列。与肾母细胞瘤不同，肾母细胞瘤需要化疗或多模式治疗以达到最佳治疗效果，现有证据表明，胚胎性腺瘤通过单纯剜除术或肾切除术很可能治愈。两名女性，年龄分别为54岁（病例1）和78岁（病例2），因影像学上边界清晰的肾病变伴血尿接受了针吸活检。细胞涂片显示小的蓝色细胞呈模糊的玫瑰花结样排列，胞质稀少，核染色质细小且分布均匀。在细胞块中，这些细胞呈紧密、原始的管状玫瑰花结样排列或罕见的更实性的细胞簇。由于未发现未分化的胚基和原始肾小球被认为是取样误差，病例1做出了提示肾母细胞瘤的诊断。肾切除术中，尽管进行了广泛取样，但未见到典型的三相肾母细胞瘤形态以及间变或坏死区域。鉴于结构单一，病例1的诊断修正为胚胎性腺瘤。病例2经细胞学诊断为肾胚胎性腺瘤，目前正在进行保守观察。我们认为，细胞学/组织学上单一结构的存在对肾胚胎性（后肾）腺瘤与肾母细胞瘤的鉴别非常有帮助。
