Introduction/Background Standard doses of ionizing radiation inhibit antioxidant systems (AOS) and immunological reactivity of the body (IRB) in patients with cervical cancer (CC). Our purpose was to analyze AOS and IRB parameters at fractionation of doses of ionizing radiation (FDIR).

Methodology The study included 69 patients with T3NxMo CC receiving FDIR: single dose of 2 Gy daily, 5 fractions per week, intracavitary 60 Co therapy 5 Gy twice a week. The total dose at the point A 85±3.6 Hz, point B 59.5±2.2 Hz. AOS and IRB at 10 Gy, 20 Gy and 40 Gy were studied. Comparison group included 45 healthy women.

Results FDIR 10–20 Gy mobilized endogenous AOS: the content of vitamins A and E and E/A in leukocytes was normal, SOD/TPA decreased by 33.4% and 27%, catalase levels in neutrophils increased by 3 times vs. initial levels (p≤0.05). Imbalance in enzymatic and nonenzymatic AOC units disappeared. IRB increased: an amount of T lymphocytes with CD4+ and CD8+ markers by 33% and 60%, CIC decreased by 26% (p≤0.05). Immunoregulatory index decreased by 16.2% (p≤0.05) and was close to normal levels. The amount of natural killers increased (CD16+) by 34% (p≤0.05). At a dose of 40 Gy: E and A decreased by 5.6 and 17 times, catalase by 1.9 times (p≤0.05); SOD and TPA indicators increased by 2.4 times (p≤0.05). The absolute number of lymphocytes was suppressed due to CD4+ by 3.6 times and CD16+ by 4 times (p≤0.05). CIC levels were twice higher than initially (p≤0.05), and immunoregulatory index was lower than the norm and the data at 10 Gy by 27% and 28%, respectively (p≤0.05).

Conclusion Doses of 10–20 Gy mobilize endogenous AOS, increasing the content of E and A vitamins in blood cells, normalize the permeability and elasticity of the blood cell membranes, and stimulate the helper-inductor and cytotoxic function of leukocytes.

Disclosure Nothing to disclose.