The local accumulation of 99mTc-methoxyisobutylisonitrile (MIBI) in the mammary gland and regional lymph nodes was followed up in 9 women with breast cancer and 8 healthy women. The method if static polypositional scintigraphy was used with a spot scanning of the mammary, axillary and subclavian regions, and then the single-photon emission computer-aided tomography (SPECT) was carried out. The radiopharmaceutical accumulation in the patients was found to be appreciably higher then in the control subjects. SPECT failed to provide an additional diagnostic information as compared to the planar scintigraphy.