We studied 115 cases of EEC diagnosed on hysterectomy specimens. Double immunohistochemical staining (D2-40/CD31) was performed in all 115 cases to show LVI and BVI on the same slide. MELF pattern invasion was present in 24/115 (21%) cases. MELF-positive tumors had a higher frequency of LVI than MELF-negative tumors (58% and 23%, respectively); the frequency of BVI was twice as high in MELF-positive tumors in comparison to MELF-negative tumors (25% and 12%, respectively). These differences were significant (p ˂ 0.0001). All tumors with positive BVI also had a concomitant LVI. The presence of MELF invasion had no impact on overall survival, confirming previous studies. 5-year survival rates were almost equal in cases with negative LVSI and cases with positive isolated LVI (98% vs. 97%). However, in cases where BVI was also present, the 5-year survival rate was significantly lower, 63% (p ˂ 0.0001). Furthermore, BVI proved to be an independent prognostic factor for overall survival, disease-free survival, and recurrence in the multivariate analysis. In conclusion, MELF pattern invasion is a good predictor of lymphatic and blood vessel invasion but has no prognostic value. Our results suggest that BVI in EEC has greater clinical value than isolated LVI or myometrial invasion patterns, and the therapeutic approach should be guided by BVI presence. Therefore, we hope this study will promote the routine evaluation of BVI in the context of EEC diagnostic procedures.

Background/Objectives: MicroRNAs (miRNAs) regulate gene expression and are proposed as biomarkers in colorectal cancer (CRC). This study evaluated miR-185-5p, miR-141-5p, and miR-21-5p expression in CRC tissues; their association with tumor location, histopathology, and clinical outcomes; and the suitability of miR-16-5p and miR-151a-3p as housekeeping controls. Previous reports suggest tumor-suppressive roles for miR-185 and miR-141 and an oncogenic function for miR-21, though findings remain inconsistent. Methods: Paired tumor and adjacent normal tissues from 70 CRC patients were analyzed. RNA was extracted from FFPE samples, and miRNA expression quantified by RT-qPCR. Relative expression values were normalized to miR-151a-3p. Tumor–normal differences, localization effects, and associations with clinicopathological and outcome variables were assessed using repeated-measures ANOVA and non-parametric tests. Results: miR-185-5p and miR-141-5p were significantly reduced in tumors compared with normal mucosa while miR-21-5p was upregulated. miR-16-5p showed higher expression in normal tissue, indicating its instability and unsuitability as a housekeeping control. A modest but significant localization effect was observed for miR-185, while other miRNAs were minimally influenced by location. Baseline asymmetry between non-tumor samples, observed for miR-185-5p, further indicated sidedness effects. None of the miRNAs were associated with stage, histological type, grade, invasion, immune infiltration, progression, or five-year survival. Conclusions: miR-185-5p, miR-141-5p, and miR-21-5p show robust tumor–normal differences, supporting their diagnostic potential, while miR-16-5p is unsuitable as a housekeeper. Modest but significant localization effect was observed for miR-185 in right-sided tumors. None showed prognostic value in stage I–III CRC. Larger, location-stratified studies are warranted.