IMMUNOHISTOCHEMICAL MARKERS IN CARCINOMA BREAST: EVALUATION AND CORRELATION WITH CLINICOPATHOLOGICAL FEATURES

Background: Breast carcinoma is the most common malignancy in women and shows considerable heterogeneity in its clinical and pathological presentation. Immunohistochemical (IHC) markers such as estrogen receptor (ER), progesterone receptor (PR), and HER2/neu are essential for prognostication and treatment planning. This study was undertaken to evaluate the expression of IHC markers in breast carcinoma and to correlate them with clinicopathological parameters. Methods: A cross-sectional observational study was conducted on 100 histopathologically confirmed cases of breast carcinoma who underwent breast conservation surgery or modified radical mastectomy in the Department of General Surgery, Maharana Bhupal Government Hospital and RNT Medical College, Udaipur, between February 2024 and July 2025. Clinical details, tumor characteristics, and histopathological findings were recorded. IHC analysis for ER, PR, and HER2/neu was performed, and results were correlated with age, tumor size, histological grade, and lymph node status. Data were analyzed using SPSS version 16, with p < 0.05 considered statistically significant. Results: The mean age of presentation was 52.2 years, with most patients (53%) in the 51–60 years age group. Invasive ductal carcinoma was the most common histological type (81%), and the majority of tumors (68%) measured 2–5 cm. Stage IIB was the most frequent presentation (41%), followed by stage IIIB (23%). ER positivity was observed in 54% of cases, PR in 45%, and HER2/neu overexpression in 32%. ER and PR expression were significantly associated with older age, tumors measuring 2–5 cm, grade II tumors, and 1–3 positive lymph nodes. HER2/neu overexpression was strongly correlated with younger age, tumors >5 cm (84.3%), grade III morphology, and 4–9 positive nodes (p < 0.001). A strong inverse relationship was observed between hormone receptor negativity and HER2/neu positivity (p < 0.0001). No significant association was found between IHC markers and histological variants (p = 0.95). Conclusion: ER and PR expression correlated with favorable clinicopathological features, while HER2/neu positivity was associated with aggressive disease characteristics. IHC profiling is essential for accurate prognostication and tailored treatment in breast carcinoma.