[Can intensive induction chemotherapy eradicate retroperitoneal lymph node metastases in children over 1 year of age with stage 4 neuroblastoma?]. / Czy intensywna chemioterapia indukcyjna moze spowodowac eradykacje zmian w pozaotrzewnowych wezlach chlonnych u dzieci powyzej 1 r.z. z neuroblastoma w 4 stopniu zaawansowania?

The prognosis in patients over 1 year of age with stage 4 neuroblastoma (NBL) is poor in spite of intensive treatment. The choice of intensive chemotherapy and extension of the surgery, especially in the case when the tumor is localized in the abdomen, is still controversial. Between 1991-2001 there were 61 patients with NBL treated in our Department; 28 of them were older than 1 year and had stage 4 with the tumor localized in the abdomen. All children received intensive chemotherapy according to Japanese protocol. Three children with disease progression during intensive treatment where excluded from further analysis. In 22 children with good or very good response to chemotherapy, the surgery was performed. In 4 patients it was local surgery. In 18 patients the tumor was removed with all visible retroperitoneal lymph nodes (so called Tsuchida surgery). The histopathological evaluation was performed in 17 patients with Tsuchida surgery and in 13 cases metastases in retroperitoneal lymph nodes were found. The 5-year overall survival was significantly better in the group with Tsuchida surgery performed (0.66 vs 0.21, p=0.044) for the patients in stage 4. After the intensive induction of chemotherapy the metastases in retroperitoneal lymph nodes can still be found. The removal of the tumor with all retroperitoneal lymph nodes can improve treatment results in patients with advanced abdominal neuroblastoma, but it is necessary to investigate more patients and to prolong the observation period.

[Perspectives in the use of imatinib in the treatment of childhood cancers]. / Perspektywy zastosowania imatinibu w leczeniu nowotworów dzieciecych.

Introduction of novel diagnostic methods and multimodal therapy has resulted in about 70% probability of cure of childhood neoplasms. However, treatment results of some neoplastic diseases in children, including chronic myelogenous leukemia (CML) still remain unsatisfactory. The only chance of cure remains allogeneic hematopoietic stem cell transplantation, however availability of transplantation is still low as a limited number of donors is available. In neoplastic diseases in which treatment results remain poor, intensification of treatment components (chemotherapy, radiotherapy) did not succeed in improving the treatment results. In recent years no improvement was made in gene therapy. With introduction of new drugs that selectively inhibit mechanisms of maturation and proliferation of cancer cells, new hope has arisen. In our paper we present the mechanism of action of imatinib, the tyrosine kinase inhibitor which was employed in the treatment of CML and gastrointestinal stromal tumors. Currently, there are several ongoing studies assessing the efficacy of this novel drug in the therapy of brain tumors, neuroblastoma, lung and prostate cancer.