Diagnosis of Bone and Joint Tumors Plain x-rays MRI, usually initially without and then with contrast, and sometimes CT Whole-body bone scan or whole-body PET-CT (positron emission tomography combined with CT) if multicentric or metastatic tumors are suspected Biopsy unless imaging studies clearly show benign characteristics or if there are multiple bony lesions consistent with metastatic disease in a patient with a confirmed active primary cancer The most common reason that diagnosis of bone tumors is delayed is that physicians fail to suspect the tumor and order appropriate imaging studies.