Published online Sep 6, 2019. doi: 10.12998/wjcc.v7.i17.2580
Peer-review started: March 15, 2019
First decision: June 19, 2019
Revised: July 11, 2019
Accepted: July 27, 2019
Article in press: July 27, 2019
Published online: September 6, 2019
Mixed epithelial and stromal tumors of the kidney (MESTKs) are a rare entity (about a hundred cases reported). They occur almost exclusively in postmenopausal women, with only seven cases reported in men. As this entity is very rare, little is known on its imaging features, especially magnetic resonance imaging (MRI) findings. In women, at MRI, the cystic component shows T1 hypointensity and T2 hyperintensity, while the solid component shows T1 hyperintensity and T2 hypointensity.
We report the computed tomography (CT) and MRI findings of MESTK in a 19-year-old male adolescent. To our knowledge, this case report is the first report of MRI findings of MESTK in male adolescents. The patient was admitted to Subei People's Hospital (Jiangsu Province, China) in July 2017 after a renal mass on the left side was detected by ultrasound during a clinical examination. Blood tests were all normal. Non-enhanced CT showed a round, well-circumscribed complex mass, approximately 45 mm × 40 mm in size. MRI revealed a clear well-circumscribed mass with a mixed arrangement of solid and cystic components. On T2 weighted images, some hypointensities were found in the solid areas. After contrast enhancement, moderate or mild enhancement was found in the solid component, which increased with time. A radical left nephrectomy was performed. The pathology analysis revealed a mixed epithelial and stromal tumor. The patient had no imaging findings of recurrence or metastasis at 12 months following surgery.
The possibility of MESTK should be considered in male adolescents. MRI can provide useful information for the preoperative diagnosis.
Core tip: Mixed epithelial and stromal tumors of the kidney (MESTKs) are rare benign tumors that occur predominantly in women. Little is known on its imaging features, especially magnetic resonance imaging (MRI) findings. We report the computed tomography and MRI findings of MESTK in a 19-year-old male adolescent. To our knowledge, this is the first report of MRI findings of MESTK in male adolescents. Although it occurs predominantly in menopausal women, the possibility of MESTK should be considered in male adolescents with a cystic solid mass in the kidney. MRI can provide useful information for the preoperative diagnosis.