[Morphofunctional characteristics of malignant thyroid gland tumors in children from various regions of the Ukraine, who have been victims of of the Chernobyl nuclear power plant accident].
Thyroid cancers in children from the affected areas of Ukraine were investigated by means of light (33 cases) and electron (20 cases) microscopy. Statistical data from 25 regions of Ukraine have been analyzed concerning thyroid cancer in patients aged up to 18 years for the period 1981-1990. There is an increase in the number of thyroid cancers in the children of Ukraine from 0.04-0.06 cases in the "pre-chernobyl" period to 0.23 cases per 10(5) children's population in 1990. In the children operated in the Clinic of the Institute of Endocrinology in 1990-1991, severe forms of thyroid lesions with metastases to the lymph nodes were noted. Histopathological studies show prevalence of different variants of papillary cancer with presence of follicular, solid, poorly differentiated areas. Ultrastructural analysis revealed polymorphism of tumour cells, various degrees of their differentiation and functional specialization that point to a mixed multicomponent nature of carcinomas.