A STUDY OF STROMAL EXPRESSION OF ALPHA SMOOTH MUSCLE ACTIN IN PROLIFERATIVE LESIONS OF BREAST.

Background: Breast lesions are one of the common problems encountered in women. Breast cancer is the most common malignant tumor and the leading cause of cancer death in women worldwide, with > 1 million cases occurring annually and 30,000 patients die annually from the disease. The stroma immediately adjacent to a tumor is a passive structural element that elicits an immune response in an attempt to reject the tumor. CD34 brocytes undergo morphologic and phenotypic alterations characterized by the adoption of a plump myobroblast-like appearance and loss of CD34 expression, accompanied by the acquisition of a-smooth muscle actin (SMA) expression. The purpose of this study is to see the presence and distribution of smooth muscle actin positive cells in the stroma of proliferative lesions of breast. Method: A total of 65 cases out of 105 cases received over a period of three years from august 2018 to July 2021. Smooth muscle actin expression was studied in the stroma and graded accordingly. This study showed Smooth muscle actin was strong positive in stroma of malignant lesions Results: , whereas it was negative in the benign and non-neoplastic lesions. It showed Sensitivity of 100% and specicity of 89.17%. Positive predictive value was 83.87% and negative predictive value was 100%. P value was <0.001, hence signicant in malignant lesions. Smooth muscle Conclusion: actin in the stroma of proliferated breast lesions is associated with aggressive behavior of the lesion. Owing to the signicant differences in SMA expression between benign and malignant breast lesions, it can potentially be used to differentiate between the two and can serve as an important diagnostic marker.