A successful preoperative chemotherapy followed by complete resection for congenital mesoblastic nephroma: A case report

Abstract

[Case] The patient was a girl aged one year and eight months. [Clinical course] A mass in the left abdomen was noticed several days before hospitalization. Imaging revealed a giant tumor (maximum diameter of approximately 9.5 cm) that extended beyond the midline, originating near the inferior pole of the left kidney, indicative of a nephroblastoma. Owing to its large size and a strong suspicion that the tumor was dorsally adherent to the retroperitoneum, its total removal was deemed difficult. We administered preoperative chemotherapy using the International Society of Pediatric Oncology (SIOP) WT 2001 regimen, which led to a tumor reduction. Tumor resection was subsequently performed. The surgical margins were negative for tumor cells, and the pathological diagnosis was congenital mesoblastic nephroma. [Conclusion] Tumor reduction by preoperative chemotherapy facilitated the complete removal of a congenital mesoblastic nephroma. The administration of anthracyclines and radiation therapy could be avoided by using the SIOP WT 2001 regimen.