A comparative study of 18F-FDG PET/CT and ultrasonography in the diagnosis of breast cancer and axillary lymph node metastasis.

BACKGROUND

The aim of this study was to compare the diagnostic value of 18F-FDG-PET/CT (PET/CT) with ultrasonography (US) in detection of primary breast cancer and axillary lymph nodes (ALN) metastasis of breast cancer.

METHODS

One hundred and sixty four patients with breast carcinoma were recruited and analyzed retrospectively. All patients underwent PET-CT and US. The PET/CT scan results for the diagnosis of primary breast cancer were compared with US. The diagnostic accuracy of PET/CT in detecting ALN metastasis was compared with histopathology.

RESULTS

In 164 patients with cytologically established breast carcinoma, the sensitivity of PET/CT and US in the diagnosis of breast cancer were 86% (141/164), 91% (149/164), respectively. The sensitivity, specificity of PET/CT and US in ALN staging were 46% and 54%, 91% and 91%, respectively. The diagnostic accuracy of PET/CT correlated with the ALN size, the SUVmax of primary breast cancer (P=0.02 and 0.04).

CONCLUSIONS

PET/CT is very expensive, and not superior to US in detection of primary breast cancer and in ALN staging, but superior in detecting distant metastases. PET/CT cannot be recommended as a primary diagnostic procedure in early breast cancer. US should still remain the first line for the diagnosis of stage I breast cancer. In relation to the detection of axillary node metastases, both PET/CT and ultrasonography have poor sensitivity, and cannot replace staging by using the sentinel node procedure.