CLINICAL AND MORPHOLOGICAL FEATURES OF GASTROINTESTINAL LEIOMYOMAS WHICH ARE COMPLICATED BY BLEEDING

Aim: Investigation of the morphological structure of gastrointestinal leiomyomas which complicated by bleeding, and also reveal the reasons of such complications. Material and methods: There are 36 patients in the study group. All patients were hospitalized in Vinnitsa Regional Clinical Hospital during 2010-2021years with the features of acute gastrointestinal bleeding from the upper gastrointestinal tract. The verification of the tumor was carried out using histopathological and immunohistochemical studies in the postoperative period. According to the results of these studies, all patients were diagnosed with leiomyoma. Results: Among all patients hospitalized with an acute GI bleeding during 2010 - 2021, GI leiomyomas were diagnosed in 0.41%. Men accounted for 56.4%, women - 43.6%. Most of all there were patients aged 50-70 years. The size of the smallest tumor witch removed was 2.5 × 2 cm, the largest - 10 × 8 cm. In our study, leiomyomas that were complicated by bleeding were most often localized in the stomach (88.9%) and duodenum (8.3%), and only in one case (2.8%) in the esophagus. Most of the complicated leiomyomas became leiomyomas of such pathomorphological types as cellular, epitheloid and weird leiomyomas. Their histological structure has its own characteristics. The manifestations of neoangiogenesis and destruction of the blood vessels are clearly visible. There is a thin, it is extensions, all vessels are lacunars and sinusoidal. Also it has sings of angiomatosis. Immunohistochemical analysis of all leiomyomas in the study group showed a positive reaction to smooth muscle actin and desmin, and was negative for CD117 and CD34. In all complicated leiomyomas, the intensity of expression of the immunohistochemical marker of endothelial vessels CD31, which is responsible for the level of vascularization, was high, which confirms the results obtained in histopathological examination. The proliferation index of all complicated leiomyomas was below 5%, which confirms the benign nature of these tumors. But the mean expression level of Ki-67 was statistically higher for complicated leiomyomas. Conclusions: During the histopathological examination it was found that leiomyomas of the proliferative pathomorphological subspecies, which include cellular, epitheloid, and weird leiomyomas, were most often complicated by bleeding. Factors that affect the growth rate of gastrointestinal leiomyomas include the level of proliferative activity of the tumor and the level of its vascularization. Determination of the level of tumor proliferation is performed using the immunohistochemical marker Ki-67, and to determine the level of vascularization is responsible for the immunohistochemical marker CD31. Upper gastrointestinal leiomyomas, which complicated by bleeding were characterized by high levels of Ki-67 and CD31 expression. The obtained research data can be used in the selection of diagnostic and treatment management for patients with leiomyomas of the upper gastrointestinal tract.