ASSESSMENT OF INVASIVE BREAST CANCER RELEVANCE WITH HISTOPATHOLOGY AND IMMUNOHISTOCHEMISTRY FINDINGS

Background: Invasive breast cancer remains a leading cause of morbidity and mortality among women worldwide, requiring precise diagnostic approaches for effective management. Histopathological examination provides critical insights into tumor morphology and grade, while immunohistochemistry aids in identifying biomarkers essential for treatment decisions. The integration of these assessments enhances diagnostic accuracy and therapeutic planning. This study evaluates the relationship between histopathological features and immunohistochemical markers in invasive breast cancer to improve patient prognosis and personalized treatment strategies. Objective: To assess the correlation between histopathological parameters and immunohistochemical markers in invasive breast cancer and evaluate their prognostic significance. Methods: A retrospective cross-sectional study was conducted at Khan Labs and Diagnostic Centre, Lahore, over six months, analyzing 300 female patients diagnosed with invasive breast cancer. Tumor morphology, grading, lymphovascular invasion, and margin status were assessed using histopathology. Immunohistochemical analysis included estrogen receptor (ER), progesterone receptor (PR), HER2/neu, Ki-67 proliferation index, and p53 expression. Tumor classification was determined based on Nottingham grading criteria and ASCO/CAP guidelines for biomarker interpretation. Statistical analysis was performed using SPSS version 25, applying descriptive statistics, Chi-square tests (p ≤ 0.05), and multivariate logistic regression to evaluate associations between histopathological and immunohistochemical parameters. Results: Among 300 cases, 70% had invasive ductal carcinoma (IDC), 15% invasive lobular carcinoma (ILC), and 15% other subtypes. Tumor grading showed 40% low-grade, 35% intermediate-grade, and 25% high-grade tumors. Lymph node involvement was present in 45%, while lymphovascular invasion was observed in 20%. IHC analysis revealed ER positivity in 65%, PR positivity in 55%, and HER2 overexpression in 25%. The Ki-67 index was elevated (>14%) in 30% of cases, while p53 overexpression was noted in 20%. Molecular subtyping classified tumors as 40% Luminal A, 20% Luminal B, 25% HER2-enriched, and 15% triple-negative breast cancer (TNBC).Conclusion: This study underscores the critical role of histopathology and immunohistochemistry in invasive breast cancer evaluation. The strong correlation between biomarker expression and tumor characteristics highlights the importance of personalized treatment strategies. The findings reinforce the need for an integrated diagnostic approach to optimize prognosis and therapeutic outcomes in breast cancer management.