Selective estrogen receptor modulators tamoxifen,raloxifene,and bazedoxifene reduce neuronal death through the mechanisms of anti-inflammation,antioxidant stress,and inhibition of glutamate excitotoxicity.They play a neuroprotective role in cerebral ischemia and may become a new neuroprotective agent for the treatment of ischemic stroke.

Objective To investigate the biodistribution of 18F-Alfatide II in patients with breast diseases and to compare its uptake with 18F-fluorodeoxyglucose(FDG)uptake.Methods A total of 44 female patients(age:(50.7±8.0)years)with clinically suspected breast cancer from December 2015 to May 2017 were prospectively enrolled and underwent 18 F-Alfatide II and 18F-FDG PET/CT prior to treatment.By drawing regions of interest in normal organs and breast lesions,differences between 18F-Alfatide II uptake and l8F-FDG uptake were evaluated in all patients.Paired t test,two-sample t test and Wilcoxon rank sum test were used for data analysis.Results There were 53 breast lesions confirmed by histopathology in 44 patients.Among them,42 lesions were malignant and the others were benign.The uptake of 18F-Alfatide II was very low in the brain,vocal cords,lungs,blood pool and muscle.But the renal cortex and bladder had high 18F-Alfatide II accumulation.Different levels of 18F-Alfatide II uptake were found in other normal organs including normal breast tissue.There were differences(t values:2.04-41.65,all P<0.05)between 18F-Alfatide II and 18F-FDG maximum standardized uptake value(SUVmax)and mean standardized uptake value(SUVmean)in many normal organs except for the choroid plexus,salivary glands,liver,colon and normal breast tissue.The uptake of 18F-Alfatide II was significantly lower than 18F-FDG in breast cancer lesions(SUVmax:3.77±1.78 vs 7.37±4.48,SUVmean:2.25±0.98 vs 4.54±2,82;t values:4.89,4.82,both P< 0.05),but it was still higher in benign breast lesions(SUVmax:2.37±1.62,SUVmean:1.50±0.92;t val-ues:2.35,2.29,both P<0.05).Also,target/non-target(T/NT)of 18F-Alfatide II in breast cancer lesions was higher than that in benign breast lesions(5.32±3.08 vs 2.60±2.37;t = 2.72,P<0.05).Condusion The biodistribution of 18F-Alfatide II in patients is favorable and 18F-Alfatide II can be clinically used for breast cancer imaging.