Examples of IGFBP-3 immunoreactivity in infiltrating ductal carcinoma of the breast with concomitant DCIS. Immunostaining was performed as described in the Methods section, and nuclei were counterstained with haematoxylin. (a) A tumour showing cytoplasmic IGFBP-3 expression in invasive ductal cancer. (b) A similar cytoplasmic IGFBP-3 positivity in concomitant DCIS. High-power magnification (original magnification × 400).