Clinical impact of somatostatin receptor scintigraphy in the management of tumor-induced osteomalacia.

OBJECTIVE

Tumor-induced osteomalacia (TIO) is a rare condition due to phosphate wasting secondary to the release of a phosphatonin, fibroblast growth factor-23. Attempts to identify the tumor by physical examination and/or conventional imaging are sometimes unrewarding. In such cases, somatostatin receptor scintigraphy with octreotide has been successfully proposed.

METHODS

Two case reports and a review of the literature allow to demonstrate the diagnostic usefulness of octreotide and the therapeutic value of somatostatin.

RESULTS

Octreotide studies were positive in 79% of 24 reported TIO, including our 2 cases. In one of our patients with incomplete removal of the tumor, octreotide therapy was unable to improve hypophosphatemia, despite a decrease in fibroblast growth factor-23 levels by 30%. Similar results were achieved in most of the reported cases. Surgical procedures were effective in these cases and resulted in complete clinical and biochemical recovery.

CONCLUSION

We highlight the impact of somatostatin receptor evaluation in the management of TIO.