Cytotoxic and apoptotic effects of toremifene-diethylenetriamine pentaacetic acid (TOR-DTPA), formed by conjugation of TOR and DTPA, on the MCF-7 cell line were evaluated. TOR-DTPA was synthesized and qualified via gas chromatography-mass spectrometry system, thin layer chromatography, and high performance liquid chromatography methods. To screen the biological properties of TOR-DTPA at determined concentrations, our ongoing effort was to evaluate apoptotic and cytotoxic effects on the MCF-7 cell line. Trypan blue dye exclusion test, XTT, ELISA, and TUNEL assays were utilized to evaluate cytotoxicity and apoptosis. TOR-DTPA has no cytotoxic and limited apoptotic effect on the MCF-7 cell line according to the results of in vitro studies. It is concluded that the lack of obvious apoptotic and cytotoxic effects allows the already proposed ligand, TOR-DTPA, to be improved as a novel hydrophilic ligand for breast imaging.