Figure 1.

Microscopy pictures illustrating the patterns of Her-2 immunostaining in breast carcinoma. (a) Weak positive (1+) pattern exemplified by weak focal membrane staining seen in more than 10% of the tumor cells. (b) Intermediate (2+) pattern, showing weak to moderate complete membrane staining in more than 10% of the tumor cells. (c) Strongly positive (3+) pattern shows intense membrane staining with weak to moderate cytoplasmic reactivity in more than 10% of the tumor cells. Her-2 overexpressing cases comprised only those having strongly positive (3+) patterns of immunostaining.