What happened, in summary

A 75-year-old woman had been living with breast cancer since 2014. The disease spread to her liver in 2016, bone in 2017, and lymph nodes and a kidney in 2020. She had received several forms of treatment, including chemotherapy, radiotherapy, endocrine therapy and immunotherapy. By August 2020, she was receiving third-line palbociclib plus fulvestrant and joined a supervised exercise study.

During the seventh month of the program, her trainer noticed subtle changes in balance, coordination, eye movements and exercise performance. The patient also described feeling groggy and having difficulty initiating walking, but the changes were not obvious during routine medical care. After the trainer contacted her oncologist with permission, brain MRI was arranged and showed multiple metastases, mainly involving the cerebellum.

She began whole-brain radiotherapy about 4 weeks after the MRI. The case emphasizes how repeated observation during supervised exercise helped identify neurologic deterioration before more obvious signs appeared. She died 5 months after the brain metastases were diagnosed, roughly 7 years after her original breast-cancer diagnosis.