Multicentre Assessment of G-CSF and dose Intensity of Chemotherapy - Non-interventional Study (MAGIC)

Chemotherapy patients often have their doses reduced or delayed because their infection-fighting white blood cells drop to dangerously low levels—a condition called neutropenia that can be fatal. This study examines whether giving a drug called G-CSF as a preventive measure helps breast cancer patients receive their full, planned chemotherapy doses on schedule. The problem is real and measurable. When neutropenia forces doctors to cut back chemotherapy, patients may have lower chances of survival. G-CSF is known to shorten the duration of neutropenia and reduce febrile neutropenia—a severe infection-related complication—but its real-world impact on maintaining full chemotherapy dose intensity in breast cancer patients is not well documented. The researchers will retrospectively extract data from routine clinical practice across multiple UK hospitals, without direct patient contact. They will analyse how often patients who received G-CSF as primary prophylaxis completed their planned chemotherapy at full dose intensity. If the results show that G-CSF consistently helps patients maintain full chemotherapy doses, this could change standard practice. More patients might receive G-CSF preventively, potentially improving survival rates for breast cancer by ensuring they get the chemotherapy their doctors originally intended.