EM-based medical technologies are receiving increasing interest in the global scientific community. One of the most studied applications in this field is the use of microwaves for cancer diagnosis, particularly for breast cancer detection, made possible by the significant dielectric contrast between healthy and neoplastic tissues. Several microwave imaging prototypes for breast cancer detection have been proposed, some even tested in pre-clinical settings on volunteers and patients, demonstrating reasonable target detection capabilities in dense/medium-dense tissues. In this seminar, an overview of the work done and on-going at the University of Pavia investigating the potential of millimeter (mm-) waves for early-stage breast cancer detection in fat tissues will be disclosed. In particular, the main design steps will be shown and critically discussed. In addition, the perspectives of multi-modal approaches (based on mm-waves, Ultrasounds, and elastography) to improve the cancer detection capabilities in different breast compositions will be presented. Montreal, Quebec, Canada, H3A 0E9, Virtual: https://events.vtools.ieee.org/m/358922