Curious Contiguous Cells

The intricate bluebell-like structure in this image shows human breast tissue. Marked in red, we can see an irregular cluster of contiguous oestrogen receptor cells, which regulate tissue growth.
These cells are hidden within the part of the breast where milk is created and stored, known as the terminal ductal lobular unit.
This change in the patterning of cells was found in women who carry a faulty BRCA2 gene and are at high risk of developing breast cancer. Around 70% of carriers will develop the disease over their lifetime.
Finding an early change in this part of the breast is curious because these regions are usually where breast cancer starts. These hidden red cells may indicate changes related to cancer.