Endometrial Hormonal Receptor Expression and Blood Vessel Density in Abnormal Uterine Bleeding: A Cross-sectional Descriptive Study

Abstract

Introduction: Abnormal uterine bleeding (AUB) is bleeding which is abnormal in amount, duration, frequency, and cyclicity and differs from the normal pattern. The aim of the study is to evaluate the expression of endometrial estrogen (ER) and progesterone receptor (PR) immunohistochemically and blood vessel density in AUB patients. Furthermore, we will correlate hormonal receptor expression and blood vessel density with various endometrial pathologies presenting with AUB. Materials and Methods: A cross-sectional study of 60 cases with clinical diagnosis of AUB, (30 cases of cyclical endometrium and 30 cases of hyperplasia/carcinoma) was done. Histological typing of endometrial lesions was done. Microvessel density (MVD) was calculated by counting the average number of blood vessels/10 HPFs. Evaluation of MVD was done on hematoxylin and eosin (H and E) stain and also reticulin stain which highlighted the basement membrane. Immunohistochemistry for steroid hormone receptors, ER and PR was done as per avidin-biotin technique with Diaminobenzidine as the chromogen. Carcangiu scoring system for semiquantitative analysis of ER/PR expression in endometrial samples was adopted. Results: There was a significant difference in microvessel density between different histopathology microscopic diagnoses (P < 0.05). The mean value of microvessel density on reticulin stain was significantly higher as compared to the mean value of MVD on H and E. A decrease of the hormonal receptor expression, ER and PR was observed in parallel with the decreased histological degree of differentiation, the lowest values occurring in the case of endometrioid Grade 3 carcinomas. Conclusion: Angiogenesis is significantly correlated with increasing severity of the lesion. The correlation of immunohistochemical findings with histologic grade can be useful in predicting biological behavior in patients.