17 alpha-[123I]Iodovinyl-11 beta-methoxyestradiol was injected into 19 women: group 1 (n = 8), initial evaluation of breast cancer; group 2, (n = 11) postoperative follow-up including 9 patients with bone metastases. The primary tumor (size: 8-10 mm) was visualized by breast tomoscintigraphy in 2/4 patients of group 1 with high estrogen receptor concentration (162-445 fmol/mg) and was not detectable in 4 patients with low estrogen receptor concentration (6-32 fmol/mg). Axillary lymph node metastases were detected in 1 patient of group 1 and in 1 patient of group 2. In 4 patients of group 2 with previous primary tumor containing estrogen receptors, MIVE2 uptake in bone metastases was demonstrated. MIVE2 scintigraphy is an original, specific and non-invasive method for breast cancer estrogen receptor imaging in primary and in metastatic tumors.