Length Scale Matters: Real-Time Elastography versus Nanomechanical Profiling by Atomic Force Microscopy for the Diagnosis of Breast Lesions

Figure 6

The nanomechanical signature of prevailing breast cancer types. (a) (Left, top) Post-AFM histological overview of the entire biopsy exhibiting invasive ductal breast carcinoma with reference to the areas A1/A2 mapped in detail on the right (scale bar, 200 μm). (Left, bottom) Biopsy-wide stiffness distribution showing stiffness heterogeneity with a prominent soft peak around 0.6 kPa followed by the second peak at around 3 kPa characteristic of the malignant phenotype. Local histology analysis (A1/A2 top, right) of mapped regions revealed high abundance of cancer cells tending to form glandular structures typical for the invasive ductal carcinoma surrounded by the ECM. This is revealed in more detail in the representative high-resolution stiffness maps (A1/A2 middle; scale bar 6 μm) and by the corresponding bimodal stiffness distributions (A1/A2 bottom). (b) (Left, top) Post-AFM histological overview of the lobular carcinoma with reference to the areas B1/B2 mapped in detail (scale bar, 200 μm). (Left, bottom) Biopsy-wide stiffness distribution shows broader heterogeneous stiffness distribution than in the case of ductal carcinoma with values up to 20 kPa and prominent soft peak at 0.6 kPa. Local histological analysis (B1/B2 top, right) revealed areas with less cohesive cellular regions with cells that tend to invade in single file. This is also illustrated by the high-resolution stiffness map (B1/B2 middle; scale bar 6 μm) and corresponding stiffness distribution (B1/B2 bottom).