Figure 3

Immunohistochemical expression of FOXM1 in normal breast tissue as well as in non-invasive and invasive breast tumours using a tissue microarray. (A, B) Normal breast tissue is detected with very weak FOXM1 expression in the nucleus (IRS = 1) and weak FOXM1 expression in the cytoplasm (IRS = 4). (C, D) In ductal carcinoma in situ of high grade type nuclear FOXM1 expression is a little more intense (IRS = 2) than in normal breast tissue whereas the cytoplasmic FOXM1 expression is strong (IRS = 9). (E, F) In invasive breast carcinoma FOXM1 expression was often stronger in the nucleus (IRS = 3) as well as in the cytoplasm (IRS = 12) compared with normal breast tissue and ductal carcinoma in situ. (G, H) In tubular breast carcinoma, a rare variant of invasive breast carcinoma with a more favourable prognosis than invasive ductal breast carcinoma, nuclear and cytoplasmic FOXM1 expression (each IRS = 3) was weaker than in most invasive ductal breast carcinomas and stronger than in most normal breast tissues. Magnifications: A, C, E, G: 100×; B, D, F, H: 400×.