Hello, I can understand your concern. Ultrasound and MRI tests examine the soft tissues in the area and diagnose if any abnormal tissue growth like tumor or cyst is present. Usually, tumor of any kind looks same in MRI/Ultrasound report and it is very difficult to say whether growth found in the test is benign or cancerous. Biopsy is a test which examines the actual tissue cells removed by surgery or excision under microscope and can differentiate one type of tumor from the other. There are some specific characteristics of cancerous cells that make them different from normal cells when examined under microscope. Thus, biopsy results are considered benchmark to diagnose a specific tumor or growth. Thus, I do not find anything fishy in the process you have described. The diagnosis of cancer is usually reached in this same manner. I would comment that if these tests and possible results were explained to you before results and what they diagnose, you would have spared confusion. I hope this explanation helps you. Thank you for choosing HealthcareMagic. I wish your mother good recovery! Best, Dr. Viraj Shah