ACUTE AND LATE TOXICITY WITH CHEMORADIOTHERAPY FOR OROPHARYNGEAL CANCER DEPENDING ON THE FRACTIONATION OPTION

Background: Chemoradiotherapy fractionation regimen has been developed to reduce the frequency and severity of acute and late toxicity of normal tissues. Purpose: To reduce the incidence and severity of acute and late toxicity in patients with cancer of the oropharyngeal zone stages III-IVA, B by using chemoradiotherapy with dynamic accelerated hyperfractionation with concomitant boost. Material and methods: The data of 280 patients with squamous cell carcinoma of the oral cavity, tongue, oropharynx and hypopharynx stages III-IVA, B were analyzed. In the main group the altered fractionation radiotherapy was conducted. In the control group conventional radiotherapy was used. A comparative evaluation of the effectiveness of radiotherapy with conventional and altered fractionation regimens was conducted. Results of research: In the main group, grade 2 (63,6%) acute oral mucosa toxicity predominated, and in the control group grades 3 (47,5%) and 2 (41,6%) (p <0,001) were most common. Grade 1 acute skin toxicity was present in 53% cases in the main group, while in the control group grade 2 skin reactions developed more often - 59,9% (p <0,001). Grade 1 late skin toxicity was more frequent in the main group - 75% compared to the control group - 50% (p <0,001). Conclusions: In the group with altered fractionation radiotherapy, a statistically significant decrease in the frequency and degree of toxicity was obtained.