61 yo female NSCLC EGFR on Tarceva for 18 months with good response. I have never had an MRI only PET scans, would they be of any use finding brain mets?
A PET scan does not detect brain mets well, because the entire brain lights up on them. MRI is the best scan to detect brain mets. Although a brain MRI is normally performed at initial staging, often it is not repeated unless symptoms warrant.
As Dr. Pennell has written previously:
"the PET scan does not show the brain very well and an MRI or at least a CT scan with contrast is necessary to show the brain with sufficient resolution to see small metastases. The brain uses a lot of glucose (the labeled substance that lights up on a PET scan is a form of glucose, a sugar) and so thus "lights up" on the PET scan quite a bit, making it unreliable. There are special brain PET scans that can show metastases, but these are different than the ones we use to stage patients with lung cancer." - http://cancergrace.org/forums/index.php?topic=2381.msg14271#msg14271
Yes. The typical approach is to not pursue a brain MRI for regular surveillance if a person is doing well and doesn't have new neurologic symptoms. It could potentially identify metastases, but that's not likely in someone without symptoms, so it's not standard to just do MRI scans to check periodically for problems without any symptoms to go with them.
Reply # - February 4, 2014, 09:34 AM
Reply To: MRI for brain mets
Hi katief,
A PET scan does not detect brain mets well, because the entire brain lights up on them. MRI is the best scan to detect brain mets. Although a brain MRI is normally performed at initial staging, often it is not repeated unless symptoms warrant.
As Dr. Pennell has written previously:
"the PET scan does not show the brain very well and an MRI or at least a CT scan with contrast is necessary to show the brain with sufficient resolution to see small metastases. The brain uses a lot of glucose (the labeled substance that lights up on a PET scan is a form of glucose, a sugar) and so thus "lights up" on the PET scan quite a bit, making it unreliable. There are special brain PET scans that can show metastases, but these are different than the ones we use to stage patients with lung cancer." - http://cancergrace.org/forums/index.php?topic=2381.msg14271#msg14271
JimC
Forum moderator
Reply # - February 4, 2014, 08:18 PM
Reply To: MRI for brain mets
Yes. The typical approach is to not pursue a brain MRI for regular surveillance if a person is doing well and doesn't have new neurologic symptoms. It could potentially identify metastases, but that's not likely in someone without symptoms, so it's not standard to just do MRI scans to check periodically for problems without any symptoms to go with them.
-Dr. West