12th May 2024

A 58-year-old woman presents with new-onset seizures, persistent headaches, and gradual memory decline over the past six months.

A 58-year-old woman presents with new-onset seizures, persistent headaches, and gradual memory decline over the past six months. She has a history of breast cancer treated five years ago. An MRI of the brain reveals a solitary, contrast-enhancing lesion in the right cerebral hemisphere, and a biopsy confirms metastatic adenocarcinoma consistent with her primary breast cancer.

Which is the most likely route by which this tumour spread to the brain?