SAMPLE 3-1X40

This lesion is a GSK-induced area of focal hyperplasia with atypia now called Mammary Intraepithelial Neoplasia (MIN). Compare the proliferative nature of this lesion with the adjacent normal gland.

October 3, 1999


The upper image illustrates the back to back glands of a cribriform pattern and necrosis. This would be regarded as a grade 4 lesion. Compare this with a grade 1 MIN.

This image illustrates a single layer of cells with a single layer of cells which would be a grade 1 atypia. Note the normal non-neolastic epithelium at the bottom.

4x 10x 20x 40x

October 14, 1999