Objectives: To evaluate shear-wave elastographic (SWE) features of triple negative breast cancers (TNBC) and determine useful discriminators from other types of invasive breast cancers.
Methods: SWE features of 26 TNBC were reviewed and compared to 32 non-TNBC. Qualitative SWE features of lesion colour appearance, shape and homogeneity were analysed. Quantitative features were measured: mean (El mean), maximum (El max) and minimum (El min) elasticity value of the stiffest portion of the mass, mean elasticity of the surrounding tissue (El mean surr) and lesion to fat elasticity ratio (E ratio).
Results: TNBC are more often regularly shaped (57.7 % vs. 6.2 %), while non-TNBC are more commonly red (93.7 % vs 42.3 %) and heterogeneous (68.7 % vs 42.3 %). The stiffness of TNBC is significantly lower compared to non-TNBC. The two groups could be distinguished on the basis of El max (p = 0.001), El mean (p = 0.001), El min (p = 0.001) and E ratio (p = 0.0017). Lesion to fat elasticity ratio in TNBC group was statistically significantly lower than in the non-TNBC control group (p = 0.009).
Conclusions: TNBC often demonstrate benign morphological features, are softer on SWE and have a lower lesion to fat stiffness ratio compared to the other, more common types of invasive breast cancers.
Key points: • TNBC often demonstrate benign morphological features on SWE. • TNBC present on elastography mostly as red, regularly shaped, heterogeneous lesions. • TNBC are less stiff compared to other invasive breast cancers. • TNBC have lower lesion to fat stiffness ratio than other breast cancers.
Keywords: Breast neoplasms; Elastic modulus; Elastography; Sonoelastography; Triple negative breast neoplasms.