Various histological cell types, high histological grade, extensive myometrial invasion, and the presence of lymphovascular involvement are recognized as risk factors for disease development. Individuals carrying mutations in MutL homolog 1 (MLH1), MutS homolog 2 (MSH2), MutS homolog 6 (MSH6), or postmeiotic segregation increased 2 (PMS2) genes face an increased susceptibility to both endometrial and colorectal malignancies, with a lifetime risk ranging from 40% to 60%. This research aimed to investigate the prevalence of specific immunohistochemical (IHC) markers and microsatellite instability in endometrial carcinomas and explore potential associations with patient characteristics and clinical outcomes. Out of 58 patients with comprehensive follow-up data, a subgroup of 21 cases underwent rigorous IHC evaluation, involving estrogen receptor (ER), progesterone receptor (PR), Ki67, MLH1, MSH2, MSH6, PMS2, and p53 markers. Statistical analysis, employing the χ² (chi-squared) test, was conducted to assess the connection between individual IHC markers and clinical outcomes, with particular emphasis on the influence of radiation, chemotherapy, or brachytherapy treatment, as well as the occurrence of recurrence or mortality. Notably, significant correlations were observed in cases where MSH2 and MSH6 exhibited positive results, indicating their association with the use of chemotherapy and brachytherapy. However, the analysis pertaining to International Federation of Gynecology and Obstetrics (FIGO) stage or tumor grade did not reveal any statistically significant relationships with these parameters.