Clinical impact of [18F]FDG-PET in patients with suspected recurrent breast cancer based on asymptomatically elevated tumor marker serum levels. A preliminary report

The purpose of this study was to evaluate retrospectively the impact of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) on the detection of recurrent breast cancer based on asymptomatically elevated tumor markers levels. Whole-body FDG-PET was performed in 30 patients with suspected recurrent breast cancer and asymptomatic tumor marker increase but negative or equivocal other imaging modality results. A blood sample was drawn in each case for marker assay (CA 15-3 and CEA) on the same day as the FDG-PET. All of these 30 asymptomatic patients had either CA 15-3>32 U/ml or CEA>5 ng/ml. The final diagnosis of recurrent breast cancer was established by operation/biopsy histopathological findings or clinical follow-up for >1 year by additional morphological imaging techniques. Among the 30 patients, the final diagnosis of recurrent breast cancer was established in 38 sites in 28 patients. FDG-PET accurately detected 35/38 sites in 25/28 patients with recurrence. The diagnostic sensitivity and accuracy of FDG-PET in patients with suspected recurrent breast cancer and asymptomatically elevated tumor markers were 96 and 90%, respectively. FDG-PET is a useful technique for detecting recurrent breast cancer suspected from asymptomatically elevated tumor markers levels and has an important clinical impact on the management of these patients. (author)