Monday, 15 February 2016

MRI Frequency

Is anyone getting their MRIs more frequently than every 8 weeks and/or regularly using gamma or cyber knife?

One of the support foundations recommended that I get a MRI every 6 weeks (my tumor is currently stable, dx 11/2014).  They opined that this makes it easier to catch the tumor while it is small thus lending the tumor management to either gamma or cyber-knife surgery.  Having heard stories about how fast the tumor can grow, this strategy appears to make sense to me and could allow for "routine management" of the tumor in a less invasive manner.  (I realize a multi-focal or certain tumor locations require additional considerations.)

I'm guessing that there are complications with respect to getting too much radiation (from both the procedure and MRIs), having insurance pay for it, and inconvenience of more MRIs.  It seems to me however, that perhaps these are outweighed by the benefits of potentially using gamma/cyber-knife rather than traditional surgery, taking chemotherapy, or scrambling to find an appropriate clinical trial.

Any thoughts?

Mike B


  1. Insurance might be an issue, but radiation is not. MRI's do not expose you to ionizing radiation.

  2. When I was actively being treated for my GBM, back in 1999 and 2000, My neuro-onc made sure my MRIs were spaced about six weeks apart, and sometimes in between. This was due to the aggressive nature of the disease and to the particularly aggressive nature of the form that had attacked my brain and spinal column. During the first few months of treatment each scan revealed new growth in new areas.
    It wasn’t until there had been no sign of cancer in by body for nearly three years before the schedule of MRIs began to change. At first it went to every three months, then to every four months, then to semi-annually. Now, it’s an annual experience, with an occasional one in between for good measure to eliminate potential symptoms of a recurrence.
    Medicaid/Medicare covered all those scans without question.
    As for me, I’m a big proponent of frequent scans early during treatment. What’s early during treatment is for you and your neuro-onc to figure out together.
    Because of a second primary cancer after GBM, I do my best to avoid unnecessary radiation exposure. If I were going through active treatment again, I’d ask to be tight back on the six week schedule. I’d want my neuro-onc to see what’s happening as often as possible. I’d want to know as often as possible.

    1. Sam, you have an extraordinary story. Long-term disease-free survival is uncommon, particularly as you seem to have had multi-focal recurrence. It would be helpful if you could try to describe your approach, acknowledging that is was quite some time back.

  3. Which imaging technique is most useful in monitoring the brain lesion/tumour in response to treatments like when someone is following alternative therapies...MRI/MRI with contrast and/or PET-CT?Is PET-CT of any value in monitoring the brain lesions because many advocate MRI than PET-CT in brain lesions..your kind expert views please..

    1. I'm not informed enough about PET-CT (which is a combination technique) to comment on that. But as far as PET scans go, FDG-PET (which uses a glucose analog as tracer) has limited utility in brain tumors because of the high background activity (normal brain also has a high uptake of glucose). Amino acid based PET scans such as FDOPA-PET or FET-PET are more useful for brain tumors, but only a few locations in North America seem to use them. (FET-PET is more common in Europe). These types of PET scans can detect metabolically active tumor in cases when the MRI scan cannot distinguish between active tumor and pseudoprogression/inflammation/necrosis. These scans are quite expensive as well (moreso than MRI) and so not as likely to be used for routine monitoring.

      A comparison of MRI, CT, and PET is summarized here (not specifically for brain tumors):

    2. Stephen, do you know which centers do have amino acid PET scanning capability?

    3. I don't have a complete list, but if you do a search for glioma trials with FDOPA-PET, the following institutions were trying it for glioma:
      Washington University School of Medicine (St. Louis, Missouri)
      Mayo Clinic (Rochester, MN)
      Stanford ( )
      Vancouver BC (Canada)
      Houston Methodist Research Institute PET Center (Houston Texas)
      UCLA (Los Angeles)
      University of Alberta (Canada)

    4. The tracer used in FDOPA-PET scan is an anolog of DOPA, which is derived from the amino acid tyrosine, and is a precursor of the neurotransmitter dopamine.

      Similarly FET-PET uses an anolog of the amino acid tyrosine as a tracer.

      I believe that FET-PET is common in Europe, but the only North American trial I could find was this one at Brigham and Women's Hospital in Boston:

    5. Thanks Stephen.Since FDG-PET is not ideal for assessing metabolic acivity of the glioma and in the absence of aminoacid based PET,how could we be sure if there could be any necrosis in the tumour with the lesion size being the same in plain MRI for long time(2yrs).This is when the patient(LGG) is doing treatments that are not conventional,the lesion size remains the same and being asymptomatic.
      Could MRI contrast help us in anyway to know if there is possible necrosis.Thanks.

  4. New review of amino acid PET scans in neuro-oncology

  5. Dear Stephen and all,
    May I know the significance of Tractography?The NO has advised now MRI with Tractography for LGG(left thalamic,inoperable last 2 years stable on alternative treatments).The tumour is stable with no increase in size of the lesion but there is hydrocephalus and NO advised Shunting due to fear of seizures and he advised MRI and Tractography.May I know about Tractography and how it plays a role in the management of glioma like this presented case.