During recent years, there is an accumulating evidence that high grade ovarian carcinoma is developed from the fallopian tube epithelial lesions. However, is not yet completely understood and still represents the subject of investigation. We investigated the immunohistochemical phenotype of matched fallopian tubes from the patients with different types and malignancy grades of ovarian carcinoma. Matched fallopian tubes from ovarian cancer patients were available in 260 cases, including mucinous borderline tumor (n=25), mucinous carcinoma (n=15), serous borderline tumor (n=90), low grade serous carcinoma (n=72) and high grade serous carcinoma (n=48). Immunohistochemical investigation included markers of proliferation (Ki67), apoptosis (Bcl2, p53), hormone receptors (ER, PR), epithelial differentiation (CK7), mesenchymal differentiation (vimentin, calretinin) and stem cells (CD44). The results indicate that the presence of fallopian tube carcinoma in situ is significantly correlated with the presence of high grade ovarian serous carcinoma (r=0.44, p<0.001), whilst there was no significant association with low grade and borderline serous tumors or mucinous tumors.

Ovarian cancer is the leading cause of death from gynaecological cancers worldwide. In Georgia, ovarian cancer ranks fourth in terms of prevalence, and third in terms of mortality rate. According to the latest epidemiological data, there will be 21,421 new cases of ovarian cancer and 13,770 deaths from Georgian Scientists/ქართველი მეცნიერები ტ. 4 N 5, 2022 393 ovarian cancer in the United States in 2021. Due to the lack of early screening methods and asymptomatic clinical courses, most ovarian cancer is diagnosed at an advanced stage, when the prognosis of the disease is already poor. Despite the advances in modern medical treatment and surgery, ovarian carcinoma remains the most lethal gynaecological cancer. The 5-year survival rate is 46% for all stages combined. The microenvironment of ovarian carcinomas is mainly represented by macrophages, dendritic cells, neutrophils and lymphocytes. Epithelial ovarian carcinoma-infiltrating lymphocytes (TIL) have attracted much interest in the last five years. Ovarian cancer is a heterogeneous disease concerning tumour-infiltrating lymphocytes and TILs. In terms of histological subtypes, most studies include only high-grade serous carcinomas of the ovary, and studies on other histological types are scarce. The results of our study show that the quantitative evaluation of T lymphocytes and their subpopulations does not show a statistically reliable correlation between different histological types of tumours, which may be due to the intratumoral heterogeneity and individual specificity of tumours.

Ovarian cancer represents one of the major causes of gynaecologic cancer mortality worldwide. Tumor-associated macrophages (TAM) are associated with the development and progression of ovarian cancer. TAMs are mainly represented by two types M1 and M2. We investigated the distribution of total, M1, M2 macrophages, tumor cell/macrophage ratio and M1/M2 ratio in mucinous and serous ovarian tumors. The study results showed that total TAM count is significantly higher in serous ovarian tumors, compared to mucinous tumors and the highest infiltration rate is detected in high-grade serous ovarian carcinomas. In addition, the number of M2 macrophages is significantly increased in higher-grade serous ovarian carcinomas. The evaluation of tumor/cell macrophage ratio could be used as an objective measure of macrophage infiltration in ovarian tumors.

The tumour is characterised by the presence of various amounts of lymphocytic infiltration, which is seen in different areas of cancer and has not only prognostic value the predictive value as well. Tumour-infiltrating lymphocytes (TILs) in ovarian cancer can be associated either with good prognoses or bad prognoses in some cases. The constituent which makes the tumour immune microenvironment is still under vigorous research while they may have the potential to be well modified predictive and prognostic values in ovarian cancer. The data provided by already conducted research are controversial which suggests the need for further deeper studies. Besides this fact, there is no clear determination which histological subtype of ovarian cancer is under research or in many cases all of the morphological types are united. All of these facts mentioned can clarify why the results of many pieces of research provide controversial information. It is crucial that the immune microenvironment of various morphological subtypes of ovarian carcinomas be studied separately and individually.