An early indicator of breast cancer risk may be the characteristics of the epithelial cells from the lavage fluid. These breast cells are dislodged upon lavage, they are placed onto a slide and a pathologist examines them for abnormalities. Beyond the pathological diagnosis, there may be subtle changes in the appearance of the cells. Changes in the size and shape of the cell nucleus can be measured using a computer-driven microscope that has quantitative image analysis software. Increases in nuclear area, diameter and perimeter and less uniform roundness of nuclei are known to be associated with breast cancers of higher grade. These kinds of measures have also been measured in breast biopsies that were either normal or hyperplastic, and those women with larger nuclei in completely benign breast biopsies were more likely to develop breast cancer 1-33 years later.