Figure 3

Immunohistochemical evaluation of ER-α, PR, Ki-67, HER-2/ neu in feline normal mammary gland, UH, ADH and DCIS. Strong and diffuse nuclear expression of ER-α in non neoplastic feline mammary gland (A1) and in UH (A2). ADH with patchy ER-α expression in epithelial cells (A3). Low (A4) intermediate (A5) and high grade (A6) DCIS with no ER-α expression. Immunoperoxidase-DAB. Bar = 10 μm. Strong and multifocal nuclear immunoreactivity of PR in non neoplastic feline mammary gland (B1). Lack of PR immunoreactivity in UH (B2), ADH (B3), low (B4), intermediate (B5), and high grade (B6) DCIS. Immunoperoxidase-DAB. Bar = 10 μm. Few and strong Ki-67 nuclear immunoreactivity in non neoplastic feline mammary gland (C1). UH displaying strong and scattered Ki-67 immunolabeling (C2). ADH with widespread and strong Ki-67 expression (C3). DCIS low (C4), intermediate (C5), and high grade (C6) with strong and multifocal Ki-67 positive cells. Immunoperoxidase-DAB. Bar = 10 μm. Non neoplastic feline mammary gland with strong complete cell-membrane staining for HER-2/neu. IHC score: 3+ (D1). UH displaying moderate complete membrane HER-2/neu expression in few cells. IHC score: 2+ (D2). ADH showing strong complete membrane HER-2/neu expression. IHC score: 3+ (D3). Low-grade DCIS depicting strong complete membrane for HER-2/neu expression. IHC score: 3+ (D4). Intermediate-grade DCIS showing moderate complete membrane HER-2/neu immunoreactivity. IHC score: 2+ (D5). High-grade DCIS showing strong and complete membrane HER-2/neu staining. IHC score: 3+ (D6). Immunoperoxidase-DAB. Bar = 10 μm