An international study suggests a new DNA-based test could help identify some breast cancer patients who may not need chemotherapy. Both reports describe the approach as a way to screen whether treatment is necessary, rather than relying on chemotherapy by default. The test analyzes features of a patient’s tumour DNA to determine the likely benefit of chemotherapy. According to the accounts, doctors say people with certain forms of breast cancer could safely avoid chemotherapy if the test indicates a low likelihood of benefit. The findings are presented as potentially affecting large numbers of patients, with the possibility of improving treatment decisions and sparing individuals from chemotherapy’s side effects when it is unlikely to help. The reports do not indicate that chemotherapy should be eliminated; rather, they point to more targeted use based on test results. Further details such as how widely the test would be used in routine care and its effect on long-term outcomes are framed as part of an ongoing or referenced international trial.