A comparison of Tc-99(m)-MDP and Tc-99(m)-MIBI in the detection of breast

In this study, we made an intra-individual comparison of the uptake of Tc-9 9(m)-MDP and Tc-99(m)-MIBI in breast cancer. Twenty women with large breast masses (one dimension greater than or equal to 3 cm on mammography) underw ent SPET in the supine position with both agents. All transverse sections d emonstrating tumour activity were added together and the net (total) tumour uptake in a region of interest was compared to that of surrounding tissue activity (background). We also evaluated maximum tumour uptake versus backg round activity. Tumour uptake was observed in all examinations. In constras t to MIBI, eight MDP examinations showed increased uptake in normal breast parenchyma in addition to tumour uptake. There was no significant differenc e in net tumour uptake between the two tracers and non-parenchymal (indiffe rent) background activity, but the maximum tumour activity of MIBI was sign ificantly higher than that of MDP. In the eight MDP examinations with paren chymal activity, mammograms were required to identify tumour uptake correct ly. In conclusion, MDP may provide similar images to MIBI in post menopausa l women not receiving hormone replacement therapy. For other patients, MIBI gives better tumour depiction. ((C) 2000 Lippincott Williams & Wilkins).