[Radiologic findings in non-Wilms' renal tumors in children].

OBJECTIVES: To analyze the radiologic findings of non-Wilms' renal tumors in children.

MATERIAL AND METHODS: This is a retrospective study of 26 patients with histologically confirmed non-Wilms' renal tumors. The following variables were evaluated on radiological studies: location, size, margins, necrosis, hemorrhage, calcifications, subcapsular hematoma, adenopathies, and metastases. Age and clinical presentation were also analyzed.

RESULTS: We found 11 mesoblastic nephromas (predominantly solid masses, ill-defined margins, necrosis, hemorrhage, and peritumoral collections; mean patient age, 15 years old); 7 multilocular cystic nephromas (multicystic masses, thickened septa, well-defined margins, capsule, and partial involvement of the kidney; patient age range: 5 to 12 months); 4 renal carcinomas (one with dense calcifications, one mass in the pyelocaliceal system, one with infiltration of the excretory tract, one solid infiltrating mass, retroperitoneal adenopathies, and one metastasis; age range: 2 to 15 years); one clear cell sarcoma (circumscribed solid mass with necrosis and retrocaval adenopathy in a two-year-old boy); one rhabdoid tumor (hypodense mass, ill-defined margins, retroperitoneal adenopathy, vesical clots, and synchronous intracranial tumor, in a six-month-old boy); one intrarenal neuroblastoma (infiltrating solid mass, necrosis, retroperitoneal adenopathy, and bone marrow infiltration in an eight-year-old boy); and one angiomyolipoma (tumor in the upper pole, extrarenal growth, hypoenhancing, and two fatty lesions in the contralateral kidney, in a ten-year-old patient with tuberous sclerosis).

CONCLUSIONS: Radiology, together with clinical and epidemiological data, enables the diagnostic work-up of pediatric renal tumors. Histological diagnosis remains indispensable.