WT1 and breast cancer: In matched breast cancer samples (n = 12; ×4 Grade I, ×4 Grade II, ×4 Grade III) WT1 staining was observed in tumour stromal cells, epithelial cells of adjacent benign TDLU, smooth muscle cells and endothelial cells lining the arteries, veins, and capillaries of all tumour grades (Suppl.