18F-FDG PET/CT of Breast Cancer for Preoperative Evaluation of Sentinel Node Metastasis

Abstract

Axillary lymph node (ALN) metastasis is one of the most important aspects for breast cancer patients’ prognosis; however ALN dissection it is associated with a series of long-term complications. Sentinel lymph node (SLN) biopsy was performed as another procedure to minimize the adverse impact of axillary surgery. Accordingly preoperative prediction of axillary lymph node metastasis (ALNM) by image examination or biopsy of SLN is of great significance to select patients with low risk of ALNM and avoid full axillary lymph node dissection (ALND). In this study, we evaluated preoperative evaluation of sentinel node metastasis by using 18F-FDG PET/CT to staging axillary lymph node status. We undertook a retrospective review of patient data for 275 women who had histologically confirmed breast carcinoma by needle biopsy and underwent 18F-FDG PET/CT examine between March 2015 and April 2018. ALND or SLN biopsy were performed on 268 cases and 18F-FDG PET/CT results were evaluated according to final pathological results. Of 268 patients, 137 cases (79.7%) showed ALNM by surgical histopathology analysis. And we observed that comparing with ALNM group the number of positive lymph node diagnosed by PET/CT in false positive group was significantly lower (P<0.05), while the max diameter of both breast lesion and positive lymph node diagnosed by PET/CT were longer (P<0.05).By using immunohistochemistry staining and classification of molecular subtype of breast cancer, we observed that compared with ALNM group, the ration of HER2 overexpressed breast cancer in false positive group was significantly higher (P<0.05). In conclusion, despite the low false positive rate 18F-FDG PET/CT for preoperative evaluation of sentinel node metastasis is of great value for surgeons to select patients with low risk of ALNM and avoid full ALND.