Differentiation of FDG-avid loco-regional recurrent and compromised benign lesions after surgery for breast cancer with dual-time point F-18-fluorodeoxy-glucose PET/CT scan

Objective To evaluate the ability of dual-time point F-18-fluorodeoxy-glucose (FDG) PET/CT scans to differentiate FDG-avid loco-regional recurrent and compromised benign lesions after surgery for breast cancer. Methods A total of 64 FDG-avid recurrent lesions (local tumor recurrence or lymph node metastases) in 52 patients and 38 FDG-avid compromised benign lesions after surgery in 37 patients were included in the study. FDG PET/CT study was performed at 60 and 120 min after intravenous injection of 3.5 MBq/kg FDG. The maximum SUV (SUVmax) on the early and delayed scans and the percent change of SUVmax (%ΔSUVmax) between the two time points were measured. The optimal differential parameter was determined by receiver-operating characteristic curve analysis. Results The average early SUVmax, delayed SUVmax and ΔSUVmax% were 4.9 ± 2.6, 6.0 ± 3.6 and 18.2% ± 18.8 in FDG-avid recurrent lesions, and 2.1 ± 0.8, 1.8 ± 1.0 and −17.8% ± 21.3 in FDG-avid benign lesions, respectively. Delayed SUVmax was significantly increased compared with early SUVmax in recurrent lesions ( P 2.5 alone or %ΔSUVmax > 0% alone ( P