“…Meanwhile, a variety of radioiodine-labeled estrogen derivatives for SPECT imaging of ER+ breast cancer have also been reported (Ali et al, 1993(Ali et al, , 2003 | 1333 XU et al Ali et al, 1988;Hochberg, 1979;Rijks et al, 1998;Symes et al, 1985;Yan et al, 2013). 16α-[ 125 I]iodoestradiol, 11β-methoxy substituent [ 125 I]iodovinylestradiol, and its analogs had been reported as potential single-photon-emitting ER imaging agents (Ali et al, 1988;Ali, Rousseau, Ghaffari, & van Lier, 1991;Hochberg, 1979). However, their high thyroid radioactivity uptake suggested severe deiodination occurred in vivo.…”