Stromal CD10 Expression in Breast Carcinoma and its Association with ER, PR, and HER2/neu Using Immunohistochemistry: A Cross-sectional Study

Introduction: Breast cancer is a common and deadly malignancy affecting women worldwide. Various immune markers, such as Estrogen Receptor (ER), Progesterone Receptor (PR), and Human Epidermal growth factor Receptor 2 (HER2/neu), are commonly used to assess prognosis. Currently, ongoing research aims to evaluate molecular pathways that contribute to invasion and metastasis. One important immunomarker under investigation is CD10, a zinc-dependent Matrix Metalloproteinase (MMP) that degrades bioactive peptides. CD10 expression in the tumour stroma has been associated with the biological aggressiveness of several epithelial malignancies, including breast carcinoma.Aim: To analyse the association between stromal CD10 expression and different prognostic factors, such as age, histological grade, and status of ER, PR, and HER2/neu markers, in patients with breast cancer.Materials and Methods: This institutional-based, cross-sectional study was conducted at the Department of Pathology, Nil Ratan Sircar Medical College and Hospital (NRSMC) in Kolkata, West Bengal, India over a period of one and a half years (February 2021 to July 2022). It included 120 cases of breast carcinoma diagnosed through histopathological examination of formalin fixed paraffin embedded sections, which were prepared from trucut biopsies and resection specimens referred from the Department of General Surgery, NRSMC. CD10 expression was assessed by Immunohistochemistry (IHC) in all cases and scored as negative, weak, or strong. The study examined the association between CD10 expression and the following parameters: age, histopathological grade, and the status of ER, PR, and HER2/neu markers. Data were entered into MicrosoftExcel (MS) for statistical analysis. The significance of the study was determined using the Chi-square test, and data were analysed using Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM, Illinois, US). A p-value of <0.05 was considered statistically significant.Results: The study included a total of 120 cases, with 119 cases of female breast cancer (99.16%) and one case of male breast cancer (0.84%). The mean +/- SD age of the patients was 54 +/- 5.038 years (range 44 to 67 years). The majority of cases 102 (85.00%) were diagnosed as Invasive Ductal Carcinoma (IDC), Not Otherwise Specified (NOS), followed by IDC-special types 18 (15.00%). CD10 expression was evaluated in all cases, and stromal CD10 positivity was observed in 79 out of 120 cases (65.80%), with 39 individuals (49.40%) showing weak positivity and 40 cases (50.60%) showing strong positivity. The remaining 41 cases (34.16%) were CD10 negative. Grade 3 cancers were predominant in this study 62 (51.66%). It was noted that CD10 stromal positivity increased with higher grade. Most of the cancers in this study were negative for ER, PR, and HER2/ Neu (78, 65.00%; 84, 70.00%; and 67, 55.83%, respectively). Stromal CD10 expression showed a significant association with ER (p-value=0.00001), HER2/neu (p-value=0.000089), tumour grade (p-value=0.0012), and an insignificant association with age (p-value0.264) and PR (p-value=0.256).Conclusion: Therefore, CD10 expression is strongly associated with well-established prognostic markers, namely higher tumour grade, HER2/neu negativity, and ER negativity. This indicates that CD10 can not only be used as an independent marker of poor prognosis but also as a target for the development of novel therapies.