Sørensen F B, Jacobsen F, Nielsen J B, Mommsen S
Acta Pathol Microbiol Immunol Scand A. 1987 Mar;95(2):67-81. doi: 10.1111/j.1699-0463.1987.tb00010_95a.x.
Nephroid metaplasia is an unusual lesion confined to the lamina propria of the lower urinary tract. It is defined by a characteristic histologic picture of tubular structures, formed by a single layer of cuboidal cells, surrounded by a thick basement membrane. Two main theories concerning the histogenesis of the condition have been proposed: embryonic origin, or metaplasia. Five cases of nephroid metaplasia were studied light-microscopically and by immunohistochemistry for the content of Tamm Horsfall's uromucoprotein. In addition, one case was examined by electron microscopy. The results were compared to current knowledge of the lesion obtained from a survey of the literature, with special reference to histogenesis. Morphologically, one case of nephroid metaplasia was associated with mesonephroid adenocarcinoma. It is concluded that nephroid metaplasia arises as a metaplastic lesion, nearly always in previously traumatized urothelial mucosa. The natural history of the typical nephroid metaplasia is benign, but a possible relationship to mesonephroid adenocarcinoma, representing the malignant counterpart of the lesion, is discussed in relation to the histological findings, suggesting a rare but possible malignant potential of nephroid metaplasia. The diverse nomenclature used for this histologic entity needs re-evaluation and should be changed to: nephroid metaplasia.
肾样化生是一种局限于下尿路固有层的罕见病变。它由特征性的组织学图像定义，即由单层立方细胞形成的管状结构，周围有一层厚厚的基底膜。关于这种病变的组织发生学，主要提出了两种理论：胚胎起源或化生。对5例肾样化生病例进行了光镜检查，并通过免疫组织化学检测了Tamm Horsfall尿黏蛋白的含量。此外，对1例病例进行了电镜检查。将结果与通过文献调查获得的关于该病变的现有知识进行比较，特别参考了组织发生学。形态学上，1例肾样化生与中肾腺癌相关。结论是，肾样化生是一种化生病变，几乎总是发生在先前受过创伤的尿路上皮黏膜中。典型肾样化生的自然病程是良性的，但根据组织学发现讨论了其与中肾腺癌（该病变的恶性对应物）可能的关系，提示肾样化生存在罕见但可能的恶性潜能。用于这种组织学实体的多种命名需要重新评估，应改为：肾样化生。
