1P-S7-3文本框: SOME UNUSUAL RENAL TUMORS IN THE PEDIATRIC AGE Lin JN, Hsueh C, Wang ZR Departments of Pediatric Surgery, Pathology and Radiology Chang Gung Children’s Hospital and College of Medicine, Chang Gung University, Taipei Objective: Wilms’ tumor or nephroblastoma has long been regarded as the most frequent renal tumor in the pediatric age. Because of its over- whelming majority, renal tumors other than this histology may be overlooked. Some unusual but distinct renal tumors were thus reviewed. Methods: Between 1990 and 1999, all of the renal tumors in the pediatric age (<17 years old) were reviewed. Those of histological diagnosis other than Wilms’ tumor were further reviewed by the pathologist. CT scan images were evaluated by the radiologist without knowing the diagnosis. Results: Eighty cases of pediatric renal tumors were entered into this study. Among them, 15 cases (18.8%) were non-Wilms’ tumors. Clear Cell Sarcoma of the kidney (CCSK) was diagnosed in 8, Malignant Rhabdoid Tumor of the kidney (RTK) in 3, Mesoblastic Nephroma in 2, Cystic Partially Differentiated Nephroblastoma and Cystic Nephroma in one each. CT scan was suggestive but not diagnostic to that particular histology. CCSK’s were not different from classical Wilms’ tumor in terms of age, symptomatology and prognosis. However, RTK’s were younger (1, 2 and 5 months old), associated with other tumors (2 brain tumors and 1 neck sarcoma) and carried dismal prognosis (all died in 4, 4 and 6 months). Mesoblastic Nephroma and Cystic Nephroma were basically benign diseases. Conclusion: An increasing number of pediatric renal tumors other than Wilms’ tumor has been diagnosed. Physicians must be aware of these distinct entities to offer the best care to these patients.