INTRARENAL MIXED GERM CELL TUMOR

Abstract

A 2-year 10-month-old girl had poor appetite and poor activity 1 week in duration. Abdominal sonography and computerized tomography (CT) revealed a huge tumor in the left kidney with calcification and necrosis (fig. 1). Left radical nephrectomy was performed for suspected Wilms tumor. The operative finding was a large renal tumor with a smooth intact renal capsule, and multiple lymph node enlargement in the hepatic hilum and peripancreatic head area. Both ovaries were normal. Gross examination demonstrated a kidney almost completely occupied by the gray-white tumor with infiltration of the renal hilum. The tumor was 17.6 3 9.5 3 9 cm. with solid and cystic components that contained chocolate-like fluid and mucoid content. Microscopy showed features of yolk sac tumor and immature teratoma with metastatic yolk sac tumor to the pancreatic lymph nodes and mesentery. The yolk sac tumor had a reticular and tubulopapillary pattern with Schiller-Duval bodies and hyaline globules positive for periodic acid-Schiff (fig. 2, A). Immunohistochemical stain for a-fetoprotein (AFP) was positive in the yolk sac tumor. The immature teratoma was composed of skin with epidermis and hair follicle (fig. 2, B), stomach tissue with gastric mucosa and muscle wall (fig. 2, C), ciliated epithelium, neuroglial tissue, choroid plexus, bone, cartilage and primitive