[Solid tumors in the child. New advances and the importance of histological sub-classifications. II. Tumors of the peripheral nervous system, soft tissue, liver and pancreas].

According to immunohistochemical, ultrastructural features of neural cells, and identical 11; 22 chromosome translocation, at least some extra osseous Ewing's sarcoma, as well as the malignant small cell tumor of the thoracopulmonary region (Askin's tumor) are actually classified as peripheral neuroepitheliomas. Embryonal rhabdomyosarcoma, including the botryoid variant, is now, when treated with appropriate chemotherapy, a tumor of relatively favorable histology. Its prognosis is still primarily related to clinical stage and location of tumor. The alveolar subtype of rhabdomyosarcoma (including its solid variant) has a less favorable prognosis. Hepatoblastoma (epithelial or mixt variants) have the same long term survival, also mainly related to stage. Pancreatoblastoma is a tumor with well differentiated cytopathology and prolonged course, compared with other pancreatic tumors.