Multimodal imaging of mixed epithelial and stromal tumor of the kidney: Case series

To investigate the clinical features, imaging manifestations, and pathological characteristics of mixed epithelial stromal tumor of the kidney (MESTK) to improve the understanding of MESTK and the accuracy of preoperative imaging diagnosis. The clinical, imaging, and pathological data of 3 patients with MESTK confirmed by postoperative pathology were retrospectively analyzed. Three patients with MESTK were middle-aged women with no obvious clinical symptoms. The main image representation showed a multilocular cystic or solid-cystic mass, with the larger masses protruding from the kidney contour, with multiple separations, which could be of unequal thickness. The cystic component showed no enhancement on enhancement scans, whereas the segregations and solid components showed gradual and obvious enhancement. Microscopic pathology was characterized by the biphasic differentiation of mesenchymal and epithelial components. MESTK is a rare, mostly benign tumor that appears as a multilocular cystic or cystic solid, with progressive marked enhancement of the septal and solid components on enhanced scans. This imaging feature is helpful for the diagnosis of MESTK.