[Malignant tumors in infancy and childhood].

According to the report of the Institute for Medical Statistics and Documentation during the period 1980-1993, neuroblastoma was the second most common single tumor diagnosed in children (incidence 7.2%), followed by nephroblastoma (6.2%). The nephroblastoma or Wilms tumor is a malignant embryonic mixed tumor (SIOP classification) classified into five stages according to extent, infiltration of neighboring organs, metastases, and bilateral involvement. As a result of intensive interdisciplinary cooperation, this tumor has the best prognosis among the malignant tumors occurring in childhood. Depending on the histological grade, the relapse-free survival rate is 80-90%. Neuroblastoma is a malignoma of the sympathetic nervous system found in newborns and small children. In 49% of cases this tumor originates in the suprarenal glands and in 29% in the sympathetic ganglionated trunk. The classification of the INSS consists of four stages. The therapeutic concept in stages III and IV is preoperative chemotherapy and delayed operation. The prognosis depends on the stage at diagnosis. Despite pre- and postoperative chemotherapy and irradiation the results are worse than for nephroblastoma. In all stages survival is 50%, and in stage IV S 80%, and in cases of metastasis less than 20%.