G. Gurleyik (Istanbul, Turkey)
Surgical Oncology, Haydarpasa Numune Training and Research HospitalAuthor Of 1 Presentation
67P - The Role of FDG PET/CT to Omit Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy in Breast Cancer
Abstract
Background
It is controversial to perform sentinel lymph node biopsy (SNB) after neoadjuvant chemotherapy (NAC) in breast cancer (BC) due to the high false negativity rates (FNR). 18F-fluorodeoxyglucose positron emission tomography/computerized tomography (FDG-PET/CT) has been previously studied in the evaluation of response after NAC. In our study, we evaluated the diagnostic value of FDG-PET/CT for predicting ypT0 and ypN0 separately. Thus, we aimed to evaluate whether it is possible to omit SNB with prediction of pathological response by FDG-PET/CT in BC.
Methods
We evaluated 85 consecutive patients with operated BC after NAC. The maximum standardized uptake value (SUVmax) on FDG-PET/CT after NAC at both primary tumor (postSUVmax-T) and axillary lymph nodes (postSUVmax-N) were assessed to predict the ypT0 and the ypN0, respectively.
Results
We detected clinically meaningful correlation between postSUVmax-N with ypN0 in patients with human epidermal receptor-positive (Her2+) and triple-negative (TN) BC (in Her2+ BC: r=0.596, p < 0.001, in TN BC: r=0.782, p = 0.001). The postSUVmax-N predicted ypN0 with 90.5% positive predictive value (PPV) and 85.7% negative predictive value (NPV) in patients with Her2+ and TN BC. The postSUVmax-T predicted ypT0 with 87.5% positive predictive value (PPV) and 100% NPV in patients with TN BC (AUC: 0.938, P <0.01).
Conclusions
According to our study's findings, FDG-PET/CT may be an alternative to SNB to protect patients from axillary lymph node dissection when the expected FNR of the SNB is high in patients with Her+ and TN BC.
Legal entity responsible for the study
Eda Tanrikulu Simsek.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.