[Breast imaging of mass, architectural distortion and asymmetry: Clinical practice guidelines].

The development of the mammary imaging (mammography, ultrasound, MRI) enables the discovery of more and more lesions. The BI-RADS lexicon is the reference book for their descriptive analysis. Four elementary images must be individualized: masses and architectural distortion described in 3 imaging techniques, asymmetries and microcalcifications described in mammography. The aim of this work was to review three of these images: mass, architectural distortion and asymmetry, allowing the various actors involved in senology to propose an up-to-date diagnostic and interventional strategy, based on their positive predictive values (PPV) or negative predictive values of cancer and allowing the classification BI-RADS of the lesion. The masses are the most often encountered lesions as well in screening as in diagnosis. Their PPV is superior in diagnosis than in screening and it increases with the age. Their irregular forms, their spiculated outlines and their evolutionary character are the most relevant elements of suspicion. The architectural distortion is the rarest image and always classified suspect BI-RADS 4, except in case of a known scar. The asymmetry is less common; its PPV is low and rises only in case of evolutionary asymmetry.