"Screening Tissue Samples for Evidence of Cancer"

There are at least four things you can look for when examining a tissue sample for the presence of cancerous cells.

1. Each tissue type has a characteristic rate of cell division. Say for instance, in some tissues, 10% of the cells might be undergoing mitosis at any one time, while in other tissues, the number undergoing mitosis may be only 1%. Higher than expected rates of mitosis would indicate the possibility of cancerous cells.

2. Most tissue types have some features "unique" to that cell type that differentiates them from other cell types. Cancer cells often lose some of their differentiation and their appearance would be more generalized than the cells around them.

3. In most tissues, there is a great deal of connectedness. Normal cells are more flattened and maintain contacts with neighboring cells. Cancer cells become more rounded, making less contact with their neighbors.

4. Cancer cells often divide rapidly. In contrast neighboring cells may only be triggered to divide when they acquire relatively large amount of cytoplasm. So the presence of many small cells in a tissue that typically has larger cells would indicate the presence of cancerous cells.

This original document can be viewed on AskMe.com.