Tumour-induced osteomalacia.

Tumour-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by increased production of fibroblast growth factor 23 (FGF-23). A 45-year-old man presented to us with progressive weakness over 2 years along with recurrent fractures with minimal trauma. His FGF-23 was found to be above the normal range and DOTATATE positron emission tomography (PET) scan showed a well-defined enhancing soft tissue density involving the left posterior ethmoid with extension to the spheno-ethmoidal recess and sphenoid sinus ostium.