The significance of lower extremity FDG PET/CT imaging in patients with unknown primary tumor

Year 2015, Volume: 2 Issue: 6, 364 - 8, 15.07.2015

Bekir Tasdemir , Zeki Dostbil Kemal Unal Sule Yildirim Ayse Akatli

Abstract

If a suspicious finding for primary site of an unknown primary tumor (UPT) is found in limited whole-body FDG PET/CT imaging area, imaging of lower extremities is generally not performed in routine practice. This approach may not be true. In this case, FDG PET/CT imaging was performed in patient with UPT. The limited whole-body FDG PET/CT images showed an increased FDG uptake in a thyroid nodule which was seemed to be a primary lesion at first sight. But similar FDG PET/CT findings might be observed in benign thyroid nodules. So we also acquired FDG PET/CT images of the lower extremities. Then, a mass showing increased FDG uptake was seen in the left thigh. On histopathologic examination, the thyroid nodule was found to be benign and the left thigh mass was diagnosed with a malignant (hemangiopericytoma). This case demonstrates contribution of lower extremity FDG PET/CT imaging to detection of primary site of UPTs in suspected situations.

Keywords

Positron emission tomography, unknown primary tumor, field of view, lower extremity, hemangiopericytoma

The significance of lower extremity FDG PET/CT imaging in patients with unknown primary tumor

Abstract

References

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