INFLUENCE OF CHRONIC PAIN OF VARIOUS ETIOLOGIES ON THE TUMOR PROCESS IN THE EXPERIMENT
In connection with the relevance of the question of the change in the tumor process course due to the development of comorbid conditions, the influence of chronic pain of various etiologies on the dynamics of tumor growth and lifespan of white outbred rats with transplantable Guerin's carcinoma was studied. Models of chronic neurogenic and inflammatory pain were used - one-sided sciatic nerve ligation according to G.J. Bennet and the formalin into the ankle. The formation of chronic pain was accompanied by a severe decrease in the level of motor activity. On the unilateral ligation of the sciatic nerve as well as on formalin administration, along with accelerated tumor growth in some animals, an increase in life expectancy was observed compared with the maximum value in the control group (more than a third of the animals). The death of such animals occurred, as a rule, with larger tumor sizes than in rats of the control group. The results of an experimental study reflect a complex nonlinear relationship between processes caused by chronic pain, oncogenesis, and the individual characteristics of systemic regulation. The question of mechanisms of adaptation to the malignant process that contributes to maintaining the viability of the body with the continued growth of tumors and their achievement of large sizes needs to be clarified.