The aim of this study was to evaluate the diagnostic role of bone scan in patients with breast carcinoma. With this purpose, we have studied 591 patients (4 males). In 261 of them, we were able to establish the stage of disease: 33 in stage I, 137 in stage II, 71 in stage III y 20 in stage IV. Metastatic lesions were detected in 6% of patients in stage I, 8.8% in stage II, 12.7% in stage III y 50% in stage IV. Altogether, 71 from 591 patients (12%) had metastatic lesions. In 4 patients (5.3%) we obtained a false positive result. The bone lesions found in the scintigraphic studies were classified as not metastatic lesions in 236 patients (39.9%) but 26 of them were malignant (11%). Another 193 patients (32.6%) presented scintigraphic studies considered as equivocal for metastasis and 33 of them were also malignant (17%). In 150 patients scintigraphic studies did not present lesions during the follow up. In other 156 patients isolated lesions were detected and 24 of them (15.4%) were malignant. Only 4 <<cold>> lesions were detected and not any <<superscan>> image was observed in this study.