A biopsy of the tumour is often taken first to make your child's diagnosis. This involves taking a piece of tissue from the tumour so it can be looked at in the laboratory by the pathologist. They will then identify the type of cancer.
Sometimes, an operation may be dangerous or cause too much damage because of the size and position of the tumour. In this situation, chemotherapy or radiotherapy may be given before the operation to shrink the tumour and make surgery easier.