Résumé : The results of 541 pairs of radiographic and scintigraphic examinations of the skeleton formed the subject of a comparative analysis. These examinations were performed in a standardized manner on 352 patients suffering from mammary cancers, and they included 5591 regions. Apart from its homogeneity, this material met stringent criteria of selection, particularly in view of eventual follow up examination. Essentially, the analysis concerns the following points: percentage and significance of concordances and discordances with the later development of these cases; sensitivity and specificity of the 2 methods. Stress is laid on the difference between the 2 examinations as regards function: diagnostic initiation for scintigraphy, aetiological assertion for radiology. In consequence, a plan of investigation combining the 2 examinations has been proposed. Lastly, recommendations have been formulated with a view of valorizing the radiolgical interpretation by means of the isotope results.