The Clinical Characteristics of Metanephric Adenoma

Abstract

We describe the clinical presentation, diagnosis, treatment, and follow-up data of a 39-year-old woman with asymptomatic right kidney tumor, which was later histopathologically diagnosed as metanephric adenoma (MA). Macroscopically, the tumor had integrity tegument with homogeneous and gray cutting surface. Microscopically, the tumor cells were formed in adenoid or papillary pattern and contained psammoma bodies, without distinctive atypia. Immunohistochemistry results showed they were negative for creatine kinase 7, epithelial membrane antigen, and renal cell carcinoma, and positive for AE1/AE3, vimentin, and Wilms Tumor 1. Pathological diagnosis was MA. The 48 months’ follow-up information was available without recurrence.According to this case and literature review, we figured that it is difficult to make a definite diagnosis of MA only by image examination. Nephron-sparing surgery is eligible to treat MA. Long-term active surveillance is necessary because of the uncertainty of the biological behavior and cellular origin of MA.

Case Report: MRI, CEUS, and CT Imaging Features of Metanephric Adenoma with Histopathological Correlation and Literature Review

“…The metanephric adenoma is a rare epithelial tumor derived from metanephrogenic embryonic tissue, which can occur at any age but has a diagnosis peak in the fifth or sixth decade of life and a female predominance of 2:1 [ 8 , 9 , 10 ]. It features mainly characteristics of a benign tumor with a low proliferation rate and favorable outcome.…”

Una masa renal poco común en una adolescente – presentación de caso y revisión de la literatura

“…30 Existen aproximadamente 100 casos descritos en la literatura. 31 La primera descripción fue realizada por Brisigotti en 1992, luego complementada por Mostofi y col., en 1988, 32,33 no obstante existen datos que Bove y col. fue quien realiza la primera descripción en un raro caso bilateral en 1979. 28 Desde la Clasificación de los Tumores Renales de la Organización Mundial de la Salud en 2004, se clasifica como una entidad distinta con características patológicas, morfogenéticas y de comportamiento biológico único, que además, forma parte de la familia de tumores metanéfricos junto al adenofibroma metanéfrico (AFM) y al tumor estromal metanéfrico (TEM).…”

“…2 Se ha planteado estudio con biopsia por aspirado de aguja fina guiado por imágenes, sin embargo, no está protocolizado ni se tiene un perfil de seguridad conocido, y existe el riesgo de diseminación o siembra pasiva a nódulos perirrenales. 31,67,68 Tampoco ha mostrado buen rendimiento diagnóstico. 69 Así pues, en la evaluación preoperatoria durante la práctica clínica de las masas renales en adolescente, el AM es de difícil diferenciación respecto a otros tumores malignos tales como TW y pCCR.…”

Metanephric Adenoma: A Case Report of a Rare Benign Renal Tumor

“…The most common part of the kidney involved in various benign or malignant tumors is the tubular epithelium (2). MA originates from epithelial cells, and because of its commonly unspecific clinical and radiological characteristics, it can be difficult to distinguish it from malignant neoplasms preoperatively (3,4). The definitive diagnosis of MA depends on the postoperative pathological findings (5).…”

“…The definitive diagnosis of MA depends on the postoperative pathological findings (5). MA is derived from the residual renal organization during embryonic development (4). It is also considered to arise from different forms of maturation-arrested embryonic rests, persistent blastoma, or maturing nephroblastoma (6).…”