Figure 7

Illustration of tumor heterogeneity using immunohistochemistry and IHC nuclear algorithm overlay. Stained serial sections from an SSM2 ER⁺, PR⁺, Her2⁻ mammary tumor are compared. Using the algorithm overlay (a, c, e), nuclear antigens ER (a), PR (c), and Ki67 (e), stain at different intensities within the tumor. Note the more red, orange color (more intensely stained positive nuclei) in the lower part of the tumor in (a) and (c) and a more blue color (negative nuclei) in the upper part of the tumors. Ki67 staining is more evenly distributed (e). Supplementary Table S16 contains the QIA summary that documents the magnitude of the differences between the high and low areas for ER, PR, and Ki67. Structural antigens CK19 (b), CK14 (d), and CK5 (f) illustrate tumor heterogeneity with reciprocal staining. Note blue negative staining areas for CK19 (b) appear to be positive for CK14 (d) and CK5 (f) and some CK14-positive areas, negative for CK5. Scale bar length is 1 mm.