The Role of Axillary SUVmax in 18F-FDG PET/CT in Predicting the Number of Axillary Metastases of Breast Cancer

OBJECTIVETo investigate the role of positron emission tomography/computed tomography (PET-CT) in determining the maximum number of axillary lymph node metastasis (ALNM) detectable in sentinel lymph node biopsy (SLNB). STUDY DESIGNObservational study. Place and Duration of the Study: Sivas Cumhuriyet University Faculty of Medicine, Turkiye, from January 2015 to August 2021. METHODOLOGYA total of 104 breast cancer patients who underwent surgery after a PET-CT scan were examined. A receiver operating characteristic (ROC) analysis was utilised to determine optimal cut-off values for the standardised uptake values of the primary tumour (pSUVmax) and axillary lymph nodes (nSUVmax) in the presence of ALNM and the presence of more than two ALNMs. RESULTSThe presence of more than two ALNMs was associated with pSUVmax, nSUVmax, LVI, and the number of LNs detected on PET-CT. In the ROC analysis, for the ability to predict more than two ALNMs in SLNB/axillary lymph node dissection (ALND), cut-offvalues were calculated as 4.65 for pSUVmax (AUC=0.669, sensitivity=66.7%, specificity=62%, PPV=0.482, NPV=0.800, p=0.006) and 1.75 for nSUVmax (AUC=0.838, sensitivity=81.8%, specificity=88.7%, PPV= 0.676, NPV=0.913, p