Osteoid Tumors of Bone.

We present a review of several bone (osteoid)-forming tumors including enostosis, osteoid osteoma, osteoblastoma, and osteosarcoma. These entities were chosen because they are reasonably common-neither seen every day nor rare. When applicable, recent information about the lesions is included.

Advanced Imaging in Musculoskeletal Oncology: Moving Away From RECIST and Embracing Advanced Bone and Soft Tissue Tumor Imaging (ABASTI) - Part I - Tumor Response Criteria and Established Functional Imaging Techniques.

According to the Revised Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, the majority of bone metastases are considered to be nonmeasurable disease. Traditional response criteria rely on physical measurements. New criteria would be valuable if they incorporated newly developed imaging features in order to provide a more comprehensive assessment of oncological status. Advanced magnetic resonance imaging (MRI) sequences such as diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) with dynamic contrast-enhanced (DCE) perfusion imaging are reviewed in the context of the initial and post-therapeutic assessment of musculoskeletal tumors. Particular attention is directed to the pseudoprogression phenomenon in which a successfully treated tumor enlarges from the pretherapeutic baseline, followed by regression without a change in therapy.

Advanced Imaging in Musculoskeletal Oncology: Moving Away From RECIST and Embracing Advanced Bone and Soft Tissue Tumor Imaging (ABASTI)-Part II-Novel Functional Imaging Techniques.

Functional imaging can add valuable information to conventional imaging in the settings of tumor characterization and treatment response assessment. Traditional response criteria rely primarily on physical measurements, while functional imaging can potentially give a more comprehensive evaluation of oncological status. The second part of this review article discusses advanced imaging techniques such as susceptibility-weighted imaging, tumor-associated macrophage imaging, diffusion-weighted imaging, perfusion-weighted imaging, Dixon imaging, whole-body magnetic resonance imaging, whole-body low-dose dual energy computed tomography with virtual noncalcium technique, and ultrasound elastography.