68Ga-DOTATATE for Tumor Localization in Tumor-Induced Osteomalacia

J Clin Endocrinol Metab. 2016 Oct;101(10):3575-3581. doi: 10.1210/jc.2016-2052. Epub 2016 Aug 17.


Context: Phosphaturic mesenchymal tumors (PMTs) are small, typically difficult to localize, and express somatostatin receptors. Recent work suggests imaging studies using 68Gallium (68Ga)-conjugated somatostatin peptide analogues, such as 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)TATE, which enables somatostatin receptor imaging with positron emission tomography (PET), may be useful at identifying these tumors.

Objective: Our objective was to evaluate the use of 68Ga-DOTATATE PET/computed tomography (CT) for tumor localization in tumor-induced osteomalacia (TIO).

Design: This was a single-center prospective study of patients with TIO.

Setting: The study was conducted at the National Institutes of Health Clinical Center between February 2014 and February 2015.

Subjects: Eleven subjects (six females, five males) with TIO were included.

Intervention: Subjects underwent 68Ga-DOTATATE PET/CT in addition to 111In-pentetreotide single-photon emission CT (Octreoscan- SPECT/CT) and fluorodeoxyglucose-PET/CT (18F FDG-PET/CT) scan.

Main outcome measures: Localization of PMTs on the previously described imaging modalities were determined.

Results: The tumor was successfully localized in 6/11 (54.5%) subjects (one was metastatic). The tumor was identified by 68Ga-DOTATATE in all six cases. Both Octreoscan-SPECT/CT and 18F FDG-PET each identified the tumor in 4/6. In no cases was 68Ga-DOTATATE the only imaging study to identify the tumor.

Conclusions: In this first prospective study comparing 68Ga-DOTATATE PET/CT to Octreoscan-SPECT/CT and 18F FDG-PET in TIO localization, 68Ga-DOTATATE PET/CT demonstrated the greatest sensitivity and specificity, suggesting that it may be the best single study for localization of PMTs in TIO.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Cyclams
  • Female
  • Fluorodeoxyglucose F18*
  • Gallium Radioisotopes*
  • Heterocyclic Compounds*
  • Humans
  • Male
  • Middle Aged
  • Multimodal Imaging
  • Neoplasm Metastasis / diagnostic imaging
  • Neoplasms / diagnostic imaging*
  • Neoplasms, Connective Tissue / diagnostic imaging*
  • Osteomalacia
  • Paraneoplastic Syndromes
  • Positron Emission Tomography Computed Tomography / methods*
  • Prospective Studies
  • Radiopharmaceuticals*
  • Receptors, Somatostatin / metabolism*
  • Somatostatin / analogs & derivatives*
  • Tomography, Emission-Computed, Single-Photon / methods*
  • Young Adult


  • Cyclams
  • Gallium Radioisotopes
  • Heterocyclic Compounds
  • Radiopharmaceuticals
  • Receptors, Somatostatin
  • Fluorodeoxyglucose F18
  • Somatostatin
  • cyclen
  • pentetreotide

Supplementary concepts

  • Oncogenic osteomalacia