<![CDATA[Introduction: Breast cancer is a leading cause of cancer-related deaths among women globally, Indonesia is no exception Biological markers such as HER2 and MAI both play a critical role in predicting prognosis of invasive breast carcinoma (IBC). These two are associated with tumor proliferation and correlate with recurrence and survival rates. The correlation between these two prognostic factors has not been extensively studied. This study aims to investigate the correlation between HER2 immunoexpression score and mitotic activity index. Method: Medical records of 60 patients diagnosed with invasive breast carcinoma histopathologically were reviewed. Patient characteristics and clinicopathological features were analyzed. The correlation between HER2 and MAI was analyzed using Kendall's Tau-B correlation, and multivariate analysis was performed. Results: There were 48 patients with no-special type (IBC-NST) and 12 patients with other types, with a mean age of 49.53 years. More than 50% of patients were HER2-negative, and only a few (16.67%) had a high MAI. The correlation between HER2 and MAI was not statistically significant. Interestingly, patients with HER2 score of 1 were seven times more likely to have a higher MAI compared to HER2 score of 3. Discussion and Conclusion: This study found no statistically significant correlation between HER2 score and MAI in IBC patients, which suggests that HER2 status may not be directly related to mitotic activity. However, further trials with larger sample sizes are needed to confirm this result.]]>
