Mixed epithelial and stromal tumor of the kidney composed mainly of solid components: A case report.

Mixed epithelial and stromal tumor (MEST) is a relatively rare lesion of mixed epithelial and mesenchymal origin, consisting of epithelial components that form cysts and stromal cells that are positive for estrogen and progesterone receptors. The present case was a 54-year-old female who presented with hematuria. Abdominal ultrasonography revealed a 41 x 30 mm tumor in the right kidney, with the tumor protruding outward in the direction of the renal pelvis. Dynamic contrast-enhanced computed tomography and magnetic resonance imaging confirmed a solid tumor in the right kidney that showed gradual contrast enhancement and contained a central non-enhancing area with the appearance of a cystic component. Based on the imaging findings, the provisional diagnosis was papillary renal cell carcinoma or angiomyolipoma with epithelial cysts. Right nephrectomy was performed and the tumor was confirmed histopathologically as MEST. We report a very rare case of MEST that was composed mainly of solid components.

[Case of Intestinal GIST with Long-Term Survival after Multidisciplinary Treatment, Including Surgical Resection for Liver Metastasis].

A 54-year-old male underwent partial resection of the ileum for gastrointestinal stromal tumor(GIST). Although it was a high-risk GIST, he was followed-up without chemotherapy. Nineteen months after the initial operation, an EOB-MRI showed a mass in the liver(S8). As it had increased in size in 4 months of follow-up, 400mg/day of imatinib was started for the diagnosis of liver metastasis. The patient experienced PR 6 months after the initiation of chemotherapy and underwent partial hepatectomy. Imatinib 400mg/day was re-administered after hepatectomy, and the disease was well controlled for 16 months. Imatinib is acceptable as the first-line therapy for unresectable and metastatic GIST. The significance of surgical intervention remains unclear for liver metastasis in GIST; however, it could remain uncontrolled with surgery alone and requires concomitant imatinib therapy. On the other hand, imatinib could be beneficial and its life-long continuation is critical, but most patients eventually develop drug resistance. Complete resection of the metastatic site along with chemotherapy could lead to reduction of secondary resistance to imatinib and prolong the survival rate.