Percent Weight Change in the Medical Supplement Group of Early Breast Cancer

This study examines whether a specific medical nutritional supplement can help early-stage breast cancer patients maintain or manage their weight during chemotherapy with doxorubicin and cyclophosphamide. Weight changes during chemotherapy can affect outcomes and quality of life. **You may be eligible if...** - You have been diagnosed with stage I, II, or III breast cancer (confirmed by biopsy) - You are receiving doxorubicin and cyclophosphamide chemotherapy at Rajavithi Hospital - Your heart's pumping function is normal or near-normal (ejection fraction ≥ 60%) - Your general health status is good (ECOG score 0–1) **You may NOT be eligible if...** - Your cancer has spread to distant organs (stage IV) - You have diabetes that requires insulin injections - Your BMI is 30 or above, or 16 or below - You have had prior chemotherapy or radiation therapy - You are pregnant or breastfeeding - You have advanced kidney disease (CKD stage 4–5) Talk to your doctor to see if this trial is right for you.