Tumor found on pelvic bone

Toddgaylor

My girlfriend had an MRI two weeks ago and a 3 centimeter tumor was found in her pelvic bone. The doctor told her he could not think of it being anything other than cancer. And he ordered another MRI which she had two days ago. We are still waiting for results. The wait is killing us. Why would he want another MRI before doing a biopsy? She said it was dark and jagged shaped. Is that any indication it is malignant? No lump has formed yet.