Tumor-induced osteomalacia (TIO) is a chronic, devastating disease. The causative tumor is usually a small benign one that is very difficult to localize. Because the presenting symptoms include diffuse bone pain, a bone scintigraphy is commonly performed to determine the cause of the pain before TIO is suspected. In this retrospective investigation, we tried to assess whether bone scintigraphy acquired will be helpful in the eventual identification of the culprit tumor.
The images of bone scan and clinical charts of total 91 patients with confirmed TIO were retrospectively reviewed. The image findings were compared with the results of other imaging studies, surgical notes, histopathologic examinations and clinical follow-ups.
In 76.9% (70 of 91) of the patients, the findings of bone scintigraphy did not correspond to the sites of the causative tumors, which were subsequently located. However, in 23.1% of the patients (21 of 91), the sites of the causative tumors corresponded to one of the abnormal technetium 99m-methyl diphosphonate activity on bone scintigraphy. More importantly, 6 tumors corresponded to the dominant activity on bone scintigraphy.
Although findings of whole-body scintigraphy are nonspecific in patients with TIO, careful evaluation of bone scintigraphy results can be helpful in guiding further evaluation in some patients.
From the Department of Nuclear Medicine, Peking Union Medical College Hospital, Beijing, China.
Received for publication January 22, 2018; revision accepted January 22, 2018.
Conflicts of interest and sources of funding: This investigation was partially supported by a research grant from National Natural Science Foundation of China (#81671722). None declared to all authors.
Correspondence to: Fang Li, MD, Department of Nuclear Medicine, Peking Union Medical College Hospital, No. 1 Shuaifuyuan, Wangfujing Street, Dongcheng District, Beijing 100730, People's Republic of China. E-mail: firstname.lastname@example.org.