Clinicopathological Study of CD34 Antigen Expression in Benign and Malignant Breast Lesions: A Cross-sectional Study

Abstract

Introduction: Breast cancer is the most frequent cancer among women. The CD34 immunohistochemical antigen serves as a tool in differentiating between benign and malignant breast lesions. It has been suggested that CD34 may be related to invasive potential. Aim: To evaluate the expression of the CD34 antigen in the stroma of benign and malignant breast lesions using the Immunohistochemistry (IHC) method. Materials and Methods: This cross-sectional study was conducted in the Department of Pathology in collaboration with the Department of Surgery at Sarojini Naidu Medical College, Agra, Uttar Pradesh, India over a period of 18 months (from January 2021 to June 2022), involving a total of 50 histopathologically confirmed cases of benign and malignant breast lesions. Postsurgical specimens, including biopsies and mastectomies, were fixed in 10% neutral buffered formalin. The initial diagnosis was made by Haematoxylin and Eosin (H&E)- stained tissue sections. Sections from the same block were subjected to IHC staining using a monoclonal antibody to the CD34 antigen, and the intensity of expression in stromal cells was graded from 0 to 3+ based on nuclear positivity: up to 5% stromal cells immunoreactive (grade-0), >5% and up to 25% (grade-1), >25% and up to 50% (grade-2), and > 50% (grade-3). The data was entered into Microsoft Excel 2007 and analysed using Statistical Package for Social Sciences (SPSS) statistical software version 19.0. The inferential statistics included the use of the Chi-square test. Results: Out of the total 50 cases evaluated, 25 (50%) were categorised as benign, and rest 25 (50%) were categorised as malignant lesions. Among the benign lesions, the most common lesion was fibroadenoma, accounting for 9 (36%) cases, followed by benign phyllode tumour, with 6 (24%) cases. Among malignant lesions, the most common lesion was Invasive Ductal Carcinoma (IDC), accounting for 23 (92%) cases. The intensity of CD34 expression was found to be significantly higher in benign as compared to malignant breast lesions. Out of the 25 benign breast cases, the maximum number of cases (19) showed Grade-3+ positivity, 5 cases showed Grade-2+, and 1 case showed Grade-0 positivity. However, among malignant lesions, maximum cases (23, 92%) showed Grade-0 on CD34 immunostaining. Conclusion: This study was undertaken to evaluate the CD34 expression in benign and malignant breast lesions which might be able to distinguish between the benign and malignant breast lesions. The most benign breast lesions express CD34 in the stroma, while it is almost totally lost in all malignant neoplasms. Loss of CD34 is associated with the tumour’s capacity for invasion. However, to determine its function as a therapeutic target in cases of breast cancer, additional research can also be done.

Keywords

• breast cancer
• immunohistochemistry
• lactating adenoma
• squamous papilloma