My friend's dad has just found out he has a hip tumor. He and the rest of the family know much more about it but my friend has been afraid to ask the details. She doesn't know if its malignant or benign. The doctors are waiting for it to grow until they do anything. I'm not even actually sure if they've done a biopsy yet. But I wanted to know more information so as to support my friend. Are most hip tumors malignant? Why would the doctors wait to do anything? I know the tumor is bothering her father and was wondering why the doctors would wait. Is that a good or a bad sign? Could it have metastasized from another area? Thank you!