DEN53, my brother had a stroke when he was 23 (he is now 29) and they found after doing many scans that he had a brain tumour. Like everyone else says, you hear the word tumour and you freak out. My brother's tumour couldnt be removed as it was too entangled, but his wasnt cancerous. So try not to worry as CAJ said, even if it is cancerous, brain surgery these days is so advanced it is amazing.
With my brother's tumour he had to have an operation while he was awake and they inserted a radioactive chip into the tumour, which is left in for 28 days, which shrinks the tumour, and then the chip is taken out. He has scans every 9 months, and in 5-6 years the tumour hasnt grown at all.
So stay positive and support your friend all you can. You can find it is usually more difficult for the loved ones than it is than the actual person with the tumour!
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