[Classification of early and late radiation reactions and injuries]. / Klasyfikatsiia rannikh i piznikh promenevnykh reaktsii ta uskladnen'.

Radiation tolerance of normal tissues remains the limiting factor for delivering crucial tumoridical dose. The late toxicity of normal tissues is the most element of an irradiation: somatic, functional and structural alterations occur during the actual treatment itself, but late effects manifest months to years after acute effects heal, and may progress with time. The optimal therapeutic ratio ultimately requires not only complete tumor clearance, but also minimal residual injury to surrounding vital normal tissues. The disparity between the intensity of acute and late effects and the inability to predict the eventual manifestations of late normal tissue injury has made radiation oncologists recognize the importance of careful patient follow-up. There is so far no uniform toxicity scoring system to compare several clinical studies in the absence of a "common toxicity language". This justifies the need to establish a precise evaluation system for the analysis of late effects of radiation on normal tissues. The current proposed scales are not yet validated, and should be used cautiously. The present toxicity scale for acute and late radiation complications is not complete. It bases on analyses and additions of existent system as CTC (Common Toxicity Criteria) and SOMALENT by EORTC/RTOG. Current classification can be used for quantitative definition of complications' grade and for treatment planning.

[Current status and perspectives of using radioprotectors in clinical practice]. / Suchsnyi stan ta perspektyvy zastosuvannia radioprotektoriv u klinichnii praktytsi.

In this contribution an attempt is made to look at the theoretical aspects of effects of radioprotectors. Experimental and clinical data were presented. Sulfhydryl compounds are the most effective radioprotectors known nowadays, but there are two main problems of its using. The first one is their toxicity and the second--short-ranged activity. The unique radioprotector widely used in clinic on application of cytostatic therapy is amifostine. Many clinical trials have shown amifostine first of all to be useful in managing xerostomia in patients with head and neck tumors after receiving polychemotherapy. Low-to-moderate doses of some agents such as nitroxides, adrenoceptor agonist etc were found to have radioprotective activity in experiments but their application in clinic remains doubtful.