Increased Activity Due to Fractures Does Not Significantly Affect the Accuracy of 68Ga-DOTATATE PET/CT in the Detection of Culprit Tumor in the Evaluation of Tumor-Induced Osteomalacia.

OBJECTIVE

Ga-DOTATATE PET/CT is currently the most common imaging modality in localizing culprit tumors, which can result in tumor-induced osteomalacia (TIO). Fracture, which is one of the most common consequences of the TIO, can also lead to increased Ga-DOTATATE activity and potentially affect the accuracy of Ga-DOTATATE PET/CT imaging. The aim of this investigation is to evaluate whether the increased Ga-DOTATATE activity at the sites of the fracture will cause interpretation difficulty in the localizing the culprit tumor causing TIO.

METHOD

The images of Ga-DOTATATE PET/CT scan from a total of 54 patients who had multiple foci of increased Ga-DOTATATE PET/CT on PET/CT were retrospectively analyzed. Not only was the intensity of the activity on PET but also the appearance of the activity on CT taken into consideration when the interpretation of the images occurred. The results from imaging analysis were compared with the clinical chart record. All patients had tentative clinical diagnosis of TIO.

RESULTS

The causative tumors in 53 patients were eventually identified. In 1 patient, the causative tumor was not identified. Among the 53 patients with confirmed TIO, 52 tumors were accurately localized.

CONCLUSIONS

Mild activity at the sites of fracture is not a major challenging factor in the interpretation of Ga-DOTATATE PET/CT in the evaluation of TIO when both intensity on PET and morphology on CT were assessed.