Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Emergency symptoms include sudden one-sided weakness, loss of consciousness, severe breathing difficulty, or a prolonged or repeated seizure.
Report new or steadily worsening headaches, seizures, weakness, balance problems, speech changes, confusion, vision changes, or repeated vomiting promptly.
Follow-up usually includes neurological examinations, review of symptoms and medicines, and repeat MRI scans.
The timing is tailored to the tumor type, treatment, recent scan results, and clinical condition.
Primary brain cancer may return near the original site or elsewhere in the nervous system, while metastatic cancer also requires monitoring of the original cancer and other organs.
Routine follow-up should also address rehabilitation, mood, sleep, memory, work or school needs, driving safety, and caregiver support.
Steroids and anti-seizure medicines should not be stopped or changed without guidance because some need to be reduced gradually or adjusted carefully.
And for anyone, someone who:
The article also says
People living beyond treatment may need monitoring for later effects involving thinking, hearing, hormones, blood vessels, or physical function.
The care plan may change if symptoms, imaging findings, or personal priorities change.
Every sign above is quoted from the sofidex article on Brain cancer. If you are not sure, err upward — it is always reasonable to be checked.