Investigating the types of changes that occur in different tumours from the same woman.

Carcinogenesis is known to be a multi-step process. There are, therefore, many somatic changes to the DNA in cancerous cells. Some of these changes will be a consequence of carcinogenesis but some of the changes will contribute to carcinogenesis. We are using stored material from breast cancers, particularly from women who have had two breast cancers, to look at the types of changes that occur in different tumours from the same woman.