Fig. 5

Immunostaining images of estrogen receptor, progesterone receptor, human epidermal growth receptor-2, and Ki-67 expression. a, b Tumor cells are negatively stained with estrogen receptor in the nuclei (× 100 magnification and × 200 magnification). c, d Tumor cells are negatively stained with progesterone receptor in the nuclei (× 100 magnification and × 200 magnification). e, f Tumor cells showed strong membrane expression of human epidermal growth receptor-2 (× 100 magnification and × 200 magnification). g, h Strong nuclear positivity of Ki-67 in > 20% of tumor cells (× 100 magnification and × 200 magnification)