Possibilities and complexities typing of children solid tumors

Summary. Routine histological investigation of neoplasm in children mostly is not enough definitive diagnostic test in their histogenetic type determination. In connection with this immunohistochemistry becomes absolutely necessary for childhood mass typing which has not been unambiguous verified by microscopy. However, it is reasonable to confirm mass type by immunohistochemistry in case when there were no principle doubts in routine colored species. It should be taken into account that histogenetic typing of childhood solid tumors in small fraction is not able to be discovered by immunohistochemical methods. In this case real help in diagnostics is provided by tumor genome research and other molecular genetics methods. But today certain tumors are not able to be typed yet as their phenotypes have been fundamentally changed in ontogenesis. For such tumors it is reasonable to determine signs which even in absence of defined histological type may be prognosis factor for both disease development and sensitiveness for treatment.