If if my mom has had a brain tumor for 15yr what are the chances its cancerous?

In a word, ZERO.

Google "benign brain tumors". You are likely to find a reference to meningioma, which is a common non-cancerous (benign) brain tumor.

initially, i'm fairly sorry to pay attention approximately your auntie, this could be an exceedingly perplexing and annoying time for you and your loved ones. no longer all concepts tumours are malignant (cancerous) - for sure if the tests come returned displaying the tumour is benign (non-cancerous) which could in straightforward terms be a powerful element. whether, because of the fact the concepts is this manner of gentle organ, any growth in there could reason huge issues, inflicting issues like loss of signt or speech or paralysis etc. each now and then however, those issues could be effectively operated on based on the place contained in the concepts the tumour is located and you're suited, it would not help to consistently look on the black area. people can and do stay to inform the story those issues - i actually desire your auntie will come by way of this.

if its been the same size for 15 years its probably benign which is good - if its getting getting bigger than its malignant which means its growing and spreading which is not good

while im not a doctor i must say that its probably benign because 15 years is a long time to have a brain tumor and it not do anything to you in those years, which is a good sign