Thanks for asking at Healthcare Magic. I read your question and I understand your concern.
Bladder tumours are of different types. Common in children are Urothelial papilloma, Urothelial papilloma of low grade malignant potential,
urothelial carcinoma of low grade malignant potential, urothelial carcinoma of high grade malignant potential.
Bladder tumours in children are commonly low grade malignant potential, superficial with no invasion of muscle of bladder.
In nutshell
tumours of bladder are rare as a whole but benign are very rare, among malignant majority are low grade malignant potential and superficial.
70-80 Percent are cured completely while 20-30 percent relapse. However metastatic lesions are very very rare.
Hope it helps best.
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Take your best care and of your baby.
Don't worry and be hopeful about the common things.
Regards
Dr Ejaz