PMC

eFigure 2 in the Supplement depicts the process of developing imaging signatures associated with receptor status (experiment 1) and HER2+ molecular subtype (experiment 2). HER2-E indicates HER2-enriched; HR, hormone receptor; pCR, pathologic complete response; PRC1, pathologic response cohort 1; PRC2, pathologic response cohort 2; and TN, triple negative.

A, Co-occurrence of local anisotropy gradients (CoLlAGe) feature expression maps visualize the elevated disorder of local intensity gradient orientations within the peritumoral region of HER2-E relative to non–HER2-E breast cancers. B, Imaging signature of HER2-E is also associated with pathologic complete response (pCR) to anti-HER2 therapy, with rippled enhancement patterns detected intratumorally by Laws feature and elevated local peritumoral heterogeneity captured by CoLlAGe features 9 to 12 mm from the tumor characterizing both features. NAC indicates neoadjuvant chemotherapy. Radiomic feature values are unitless, thus the scale depicts relative expression values of radiomic features, standardized between 0 and 1.0 based on the range of their distribution. The blue color at 0 depicts the minimum observed feature value; the red color at 1.0 depicts the maximum observed feature value.

A, Kurtosis of Gabor features 0 to 3 mm from the tumor on magnetic resonance imaging, associated with HER2-enriched (HER2-E) status was additionally associated with B, lymphocyte density within and 0-3 mm beyond the tumor on corresponding biopsy samples. Red and blue dots indicate lymphocytes and other nuclei, respectively. Green lines denote pathologist-annotated tumor boundaries (hematoxylin-eosin; inset original magnification ×100). C, When hematoxylin-eosin–stained images are down-sampled to approximate the imaging scale (original magnification ×100), midfrequency Gabor features computed on example hematoxylin-eosin images at that magnification possess spatial association with lymphocyte density. Radiomic feature values are unitless, thus the scale depicts relative expression values of radiomic features, standardized between 0 and 1.0 based on the range of their distribution. The blue color at 0 depicts the minimum observed feature value; the red color at 1.0 depicts the maximum observed feature value.