embryonal adenoma

em·bry·o·nal ad·e·no·ma

a benign neoplasm in which the glandular epithelial elements are not fully differentiated, resembling immature tissue observed in embryonic development.
References in periodicals archive ?
Metanephric Adenoma (MA) also designated "Nephrogenic adenoma" or "Embryonal adenoma" is a rare benign renal tumour which is histologically, immunohistochemically and clinically unique, with an indolent clinicobiological behaviour.1,2 It accounts for only about 0.2% of adult renal epithelial neoplasms with only 130 well documented cases reported in world literature.3 Origin of this renal mass from persistent primitive metanephric epithelium of the proximal nephron is postulated and partly substantiated.1,2 Histologically this tumour seems to be related to epithelial Wilms' Tumour and Nephrogenic Rests and in fact these lesions may coexist.4,5