Diagnostic performance of 18F-FDG PET/CT, ultrasonography and MRI. Detection of axillary lymph node metastasis in breast cancer patients.

Abstract

The aim of this study was to evaluate the diagnostic abilities of

18F-fluorodeoxyglucose (FDG) positron emission tomography/computed

tomography(PET/CT) compared with those of ultrasonography and magnetic resonance

imaging (MRI) for axillary lymph node staging in breast cancer patients.

PATIENTS, METHODS: Preoperative 18F-FDG PET/non-contrast CT, ultrasonography and

MRI were performed in 215 women with breast cancer. Axillary lymph node

dissection was performed in all patients and the diagnostic performance of each

modality was evaluated using histopathologic assessments as the reference

standard. ROC curves were compared to evaluate the diagnostic ability of several

imaging modalities (i. e., ultrasonography, MRI and 18F-FDG PET/CT). RESULTS: In

total, 132 patients (61.4%) had axillary lymph node metastasis. The sensitivity,

specificity, positive predictive value, negative predictive value, and accuracy

for the detection of axillary lymph node metastasis were 72.3%, 77.3%, 66.7%,

81.6%, 75.3% for ultrasonography, 67.5%, 78.0%, 65.9%, 79.2%, 74.0% for MRI, and

62.7%, 88.6%, 77.6%, 79.1%, 78.6% for 18F-FDG PET/CT, respectively. There was no

significant difference in diagnostic ability among the imaging modalities (i.e.,

ultrasonography, MRI and 18F-FDG PET/CT). The diagnostic ability of 18F-FDG

PET/CT was significantly improved by combination with MRI (p = 0.0002) or

ultrasonography (p < 0.0001). The combination of 18F-FDG PET/CT with

ultrasonography had a similar diagnostic ability to that of all three modalities

combined (18F-FDG PET/CT+ultrasonography+MRI, p = 0.05). CONCLUSION: The

diagnostic performance of 18F-FDG PET/CT for detection of axillary node

metastasis was not significantly different from that of ultrasonography or MRI in

breast cancer patients. Combining 18F-FDG PET/CT with ultrasonography or MRI

could improve the diagnostic performance compared to 18F-FDG PET/CT alone.