Comparison of PET-CT and MRI for evaluation of axillary lymph nodes in early breast cancer patients

Abstract

BACKGROUND: Evaluation of axillary lymph node in women with breast cancer is very important as it can change the initial treatment decision. None of the noninvasive methods used for assessment of axilla is accurate as sentinel lymph node biopsy (SLNB) yet. This study compared the diagnostic performance of 18-fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT) and Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) in preoperative axillary evaluation of women diagnosed with early breast cancer (EBC).

METHODS: The records of 1246 patients operated for EBC between 2016-2019 were analyzed retrospectively. Pathological evaluations of axillary lymph nodes and the data of these two imaging modalities were analyzed.

RESULTS: Forty patients operated for EBC had both DCE-MRI and PET-CT. Axillary metastasis were detected in 12 patients (27.5%). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DCE-MRI/ PET-CT for determining axillary lymph node metastases were 25/66.6%, 75/67.8%, 30/47%, 70/82.6%, and 60/67.5%, respectively.

DISCUSSION: Any method has yet reached the performance of sentinel lymph node biopsy in the axillary mapping of patients with EBC. If a clinically EBC patient is suspected of axillary involvement in DCE-MRI or PET-CT (since have low PPV and sensitivity), a biopsy should be performed.