Tumor-induced osteomalacia - Current imaging modalities and a systematic approach for tumor localization

Paraneoplastic syndromes are symptom complexes that cannot be readily explained by local or distant spread of the tumor. They can occur due to hormone production, autoimmunity or other biologically active products produced by the tumor, etc. Tumor induced osteomalacia is a rare paraneoplastic syndrome in which the manifestation is mainly musculoskeletal such as bone pain, fractures and muscle weakness as a consequence of elaboration of fibroblast growth factor 23 (FGF23) by the tumor. Most of these tumors are solitary and small and hence localization of these tumors is often challenging. This review summarizes the various anatomic imaging modalities such as plain radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) and nuclear medicine imaging techniques in the evaluation of these tumors.