Is FDG maximum standardized uptake value of primary breast cancer a prognostic factor for locoregional axillary lymph node metastasis?

Abstract

Abstract Background: 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) has been widely used for diagnosis and staging of disease recurrence in breast cancer patients. Purpose: To determine the validity of 18F-FDG PET/CT maximum standardized uptake value (SUVmax) of primary breast cancer (SUVmax-T) as a prognostic factor for locoregional axillary lymph node metastasis (ALNM). Material and Methods: We prospectively studied 198 female patients with pathologically proven breast cancer. All patients were submitted to 18F-FDG PET/CT imaging for their initial tumor staging. The SUVmax-T on 18F-FDG PET/CT and ALNM were assessed. The patients were categorized into two groups; group A, with ALNM, and group B, without ALNM, according to the presence of locoregional ALNM on visual analysis of 18F-FDG PET/CT. The correlations and differences between two groups were statistically evaluated. The optimal cut-off value of SUVmax-T was determined. Results: The mean tumor size in group A was significantly greater than that in group B (P ¼ 0.0416). The mean SUVmax-T value in group A was significantly higher than that in group B (P ¼ 0.0037). Tumor stage in group A was higher than that in group B (P ¼ 0.0045). The correlation between tumor size and SUVmax-T value was statistically significant in group A (r ¼ 0.6768, P ¼ 0.0111) and in group B (r ¼ 0.7221, P ¼ 0.0280). The optimal cut-off of SUVmax-T for detecting ALNM was >4.2. As regards molecular subtypes, the mean SUVmax-T values of HER2-positive and triplenegative subtypes in group A were significantly higher than that in group B (P ¼ 0.0012 and <0.001, respectively). Conclusion: Breast cancer patients with higher primary tumor 18F-FDG uptake are at greater risk of concurrent ALNM.