A Prospective, Phase II Trial Using ctDNA to Initiate Post-operation Boost Therapy After NAC in TNBC

This study uses a blood test that detects traces of cancer DNA (called ctDNA) to guide decisions about whether patients with triple-negative breast cancer (a harder-to-treat type) need additional radiation therapy after chemotherapy and surgery. **You may be eligible if...** - You have been diagnosed with triple-negative breast cancer (a type that lacks estrogen, progesterone, and HER2 receptors) - Your cancer is stage II or III - You received chemotherapy before surgery (neoadjuvant chemotherapy) - You are 18 years or older **You may NOT be eligible if...** - Your cancer has spread to distant organs - You are pregnant - You have had prior radiation to your chest area - You have certain other serious health conditions that would prevent you from receiving radiation Talk to your doctor to see if this trial is right for you.