ERBB2 and prostate cancer: With respect to differences in the tissue expression of ErbB2, Lyne et al. [23] reported that the percentage of specimens with moderate to strong ErbB2 immunoreactivity was 100 for benign prostate basal cells, 11 for benign prostate luminal cells, 0 for benign prostate stroma, 87 for prostatic intraepithelial neoplasia and 82 for prostate cancer.