The quality of radiation treatment for oncological diseases can be influenced by a large number of factors. Among them, the breaks that occur during the course of radiotherapy play an important role. Split courses of radiotherapy are used in the practice of radiation treatment of head and neck cancer, as well as prostate cancer. Breaks between the stages of the course of radiotherapy lasting 1-2 weeks are carried out in elderly, debilitated patients or in the presence of radiation reactions of 3-4 degrees. Before the start of radiotherapy, a set of measures is taken to prevent radiation reactions. This can affect the fact that the course of radiotherapy will be carried out without interruption. Using Cox regression, it is proposed to evaluate the effect of interruptions in the course of radiotherapy on the outcome of treatment for head and neck tumors, as well as the prostate tumors taking into account the observation period.

Taking into account the important role of a number of essential trace elements in protecting the thyroid gland from the action of negative anthropogenic and natural factors in critical groups of the population living in the area where the Belarusian NPP is located, the body’s provision with selenium, zinc and iodine for primary school children and pregnant women was studied. For the first time, a significant decrease in the content of both selenium and zinc and iodine in the body of pregnant women was established in comparison with republican indicators, while in children no significant changes in the provision of these trace elements were detected. A negative correlation between the volume of the thyroid gland and the content of the trace element selenium and zinc in the body in pregnant women and in children according to Spearman was revealed. The revealed dependence may indicate potentiation of the development of goiter with a deficiency of selenium and zinc in the body.