Purpose: To evaluate the utility of FDG-PET CT metabolic activity, measured by SUVmax, in predicting pathological response to neoadjuvant chemotherapy (NACT) in breast cancer patients and to explore the relationship between tumor subtypes, receptor statuses, and treatment outcomes. Methodology: A retrospective analysis was conducted on 120 breast cancer patients treated with NACT between December 2021 and July 2024. Baseline FDG-PET CT SUVmax values were correlated with Residual Cancer Burden (RCB) scores derived from final histology. Tumor size was analyzed pre- and post-NACT using ultrasound, MRI, and mammogram imaging. Associations between tumor subtypes, receptor statuses, and treatment responses were examined. Results: The cohort included invasive carcinoma NST (57.5%), invasive ductal carcinoma (15%), and triple-negative breast cancer (TNBC) (34%). HER2-positive tumors exhibited a strong negative correlation between SUVmax and RCB (-0.304), indicating better responses to targeted therapies. In contrast, TNBC showed a weak correlation (0.004), reflecting variability in response. Mean tumor size reduction post-NACT was 13.2 mm, and 32.5% of patients achieved pathological complete response (pCR). HER2-positive tumors demonstrated the highest pCR rates, while estrogen and progesterone receptor-positive tumors showed less favorable responses to NACT. Conclusion: While FDG-PET CT SUVmax offers valuable metabolic insights, it is insufficient as a standalone predictor of NACT response, particularly in aggressive subtypes like TNBC. Combining molecular profiling with imaging data is essential to improve predictive accuracy and optimize individualized treatment strategies for breast cancer.