Uterine sarcoma: the possibility of modeling a rare tumor and providing its morphological description

Purpose of the study. To create a model of uterine sarcoma in female white mongrel rats and provide description of its morphological features. Materials and methods. In the in vivo experiment, white mongrel female laboratory rats (n = 20) weighing 250 ± 25 g were used, and the M1 strain of rat sarcoma was used as an experimental tumor model. The studied groups of animals: Group 1 (n = 10) – administration of 0.5 ml of tumor suspension containing 2.5–3.5 × 106 cells using an intravenous catheter with an injection port 22G, 0.9 × 25 mm; group 2 (n = 10) – donors of tumor material with subcutaneous M1 grafting according to the standard method. Xylazine‑ zolethyl anesthesia was used during surgical interventions. The duration of the experiment was 21 days. After killing the animals, median longitudinal histological sections were made from the tumor node, 5–7 microns thick, stained with hematoxylin‑ eosin. Results. Unlike subcutaneous grafting of sarcoma M1, the tumor growing in the uterine horn was characterized by the presence in the abdominal cavity of many nodules and tumor dropouts on the mesentery, i. e. lymph nodes. According to the cellular composition, tumors formed from a suspension of M1 sarcoma cells injected into the right horn of the uterus were characterized by a polymorphocellular type of structure against the background of pronounced neoangiogenesis. Necrosis and hemorrhages were noted in certain sections of the preparations with a polyp‑like tumor form, which corresponds to destructive signs of rapid growth and development of uterine sarcoma. Conclusion. The possibility of modeling a relatively rare tumor by introducing a suspension of M1 sarcoma cells into the right uterine horn of female rats has been established. The nature of multinodular tumor growth with pronounced polymorphism of the cellular composition, areas of necrotization and hemorrhage demonstrates the adequacy of the uterine sarcoma model for the implementation of research tasks in clinical oncology.