i have a grade 2 bilateral thalamic glioma, which can't be removed so was having scans every 3 months to monitor growth.  At my last scan in August they found another area that didn't look right and thought it may have been MS, but the biopsy showed it to be a grade 4 brain cancer, so it had appeared within 3 months and was already at a grade 4. 

I have had radio and chemo every day for 6 weeks just before Xmas and now on chemo only for another 6 months.  They aren't going to do a scan til I have finished the chemo, I find it so frustrating that I won't know if any of the treatment is making any difference until June.  

Plus I know that they can't do radio again, so even if it's made a difference to the grade 4, at some point the grade 2 will become more aggressive and they won't be able to do much more.

they have told me that average lifespan with this is 12 to 18 months, I would love to hear from people that have had the same experience and to see how they are doing.