A medical diagnostic and data processing system is disclosed. The system includes, in at least one embodiment, an arithmetic logic unit and an imaging diagnostic device that can be connected to the latter for data purposes, and a data memory in which data describing anatomical structures including lymph nodes are stored. The arithmetic logic unit is set up programmatically in such a way to produce an automatic assignment between a lymph node recorded by way of the imaging diagnostic device and data describing the lymph node that are stored in the data memory.