Osteomalacia-inducing renal clear cell carcinoma uncovered by 99mTc-Hydrazinonicotinyl-Tyr3-octreotide (99mTc-HYNIC-TOC) scintigraphy.

Most osteomalacia-causing tumors are small, benign mesenchymal neoplasms, which are commonly located in the extremities or craniofacial regions. An 18-year-old male patient with suspicion of tumor-induced osteomalacia underwent (99m)Tc-HYNIC-TOC scintigraphy to search potential culprit tumor. The images showed a large activity in the region of the left kidney. The lesion was resected and a clear cell renal cell carcinoma was found. One year after the left nephrectomy, the patient was tumor-free without symptoms of osteomalacia.