What are the key clinical features that suggest a diagnosis of metastatic brain tumours in a patient with a known primary cancer?

Key clinical features suggesting metastatic brain tumours in a patient with known primary cancer include new or changing neurological symptoms or signs. These may manifest as headaches, focal neurological deficits, seizures, cognitive or behavioural changes, and symptoms related to increased intracranial pressure.

In patients with a known primary cancer, the development of such neurological symptoms should prompt urgent investigation with standard structural MRI to identify possible brain metastases.

Additionally, the presence of extracranial disease progression or new systemic symptoms may support the suspicion of brain metastases.