Lung Cancer CT v MRI for brain metastasis check - 1262389

aliciauk
Posts:30

Hello, I am alk positive, living in UK and on crizotinib for 12 months, it is my first line treatment. I am stage 3b. As well as routine 3 month chest abdo CT scan I have a CT brain scan with contrast every 6 months, had my second brain ct today, hopefully it will be fine. Would a brain MRI be better than a CT as I understand it detects smaller lesions. My oncologist says if anything dodgy shows on CT they would do MRI then but CT could miss small lesions could it not. Oncologist says there is no evidence of any better outcome from MRI as a result of smaller lesions being detected. However she is happy for me to have an MRI if I feel more reassured by it. Do you prefer to monitor for brain metastasis by CT or MRI DR West? Many thanks Alicia.

Forums
Full Archive

Reply # - February 18, 2014, 04:10 PM

JimC
Posts: 2753

Hi aliciauk,

Many oncologists do not routinely do follow-up scans for brain metastases in the absence of prior brain mets or concerning symptoms, citing the same thinking as your doctor - that there is no evidence that finding small lesions early improves outcomes. As Dr. Weiss has said:

“I typically acquire an MRI at diagnosis, then again if symptoms suggest. Some oncologist obtain more regular MRIs. I have no objection to this, but am not convinced that it improves actual patient outcomes compared to having a low threshold to get MRI once symptoms develop.” – http://cancergrace.org/lung/topic/should-brain-mri-be-done-even-in-abse…

And in the next reply, Dr. Aggarwal agreed: “I agree with Dr. Weiss. I obtain MRI brain if symptoms (headache, blurry vision, uncontrolled nausea, seizures etc.) develop, after getting a baseline scan.”

Dr. West also agreed, stating: "I follow the same approach. It is not the standard of care at this time to do surveillance brain MRI scans after diagnosis in people with advanced NSCLC who don’t have evidence of brain involvement at their initial work-up."

As far as the difference between CT and MRI for detecting brain lesions, Dr. West has said:

"There is little to no question that head MRIs are superior to CT scans in detecting brain metastases. MRI scans detect a greater number of lesions and defines the location more readily, and they are also better at detecting spread to the meninges, the lining around the brain (and spinal cord)." - http://cancergrace.org/lung/2007/04/05/intro-to-brain-mets/

JimC
Forum moderator

Reply # - February 18, 2014, 07:41 PM

Dr West
Posts: 4735

Jim covered all of the highlights already. There is no real evidence that there is a value to doing surveillance brain scans, and that is not my routine nor that of most lung cancer specialists. That said, some of the ALK experts have noted that about half of first instances of progression in ALK-positive patients on crizotinib occur in the brain (the drug doesn't penetrate into the central nervous system), and some of them have come to favor routine brain MRIs about every 6 months. However, some of these same experts are the clinicians most likely to err on the side of practice that is pretty far from fiscally responsible on a massive, societal scale, often providing care in an academic setting that is wildly expensive but insulated from the real world concerns of cost.

In short, your oncologist is correct that there is no evidence that there is a survival benefit to aggressive brain surveillance, but if there is a group for whom it is advocated, at least by some lung cancer specialists, it is for ALK-positive patients on crizotinib.

Good luck.
-Dr. West

Previous PostNext Post