The ancient Egyptians, as described in the Ebers Papyrus, already knew that palpation—feeling for hardened lumps—can help diagnose breast cancer. Palpation is still an important element in early screening for breast cancer. On the other hand, measurements on individual cancer cells show that they are softer than the healthy epithelial cells from which they stem, which probably makes them better able to metastasize in dense human tissue. An international collaborative project led by the Soft Matter Physics Division at Leipzig University got to the bottom of this apparent paradox and has now published its findings in the journal Nature Physics.