An apparatus (1) for performing tomosynthesis and mammography of a breast (M) of a patient, comprises: an X-ray detector device (2), designed to receive and detect X-rays in a first, detection plane (3) a plurality of X-ray sources (4), which are positioned in a second plane (5) substantially at a right angle to the first plane (3) and which can be individually activated for emitting a corresponding X-ray beam (F) towards the first, detection plane (3), at least a first part (PP1) of the sources (4) being able to move relative to the detector device (2) and comprising a first source (4b) mobile in a first direction (Db) of movement parallel with the first, detection plane (3) for emitting X-rays from a plurality of operating positions along said first direction (Db) of movement a region (R2) for positioning the breast (M) a processing and control unit (6), connected to the X-ray sources (4) for activating them individually and connected to the detector device (2) for receiving a signal (s1) relating to the X-rays which passed through the breast (M) and were detected by the detector device (2), the unit (6) being designed to derive from the signal (s1) at least one radiographic image representative of the internal structure of the patients breast (M).
