The causes of cancer are complex and not fully known.However, we do know that having a family history of breast, ovarian or a related cancer can significantly increase the risk of developing breast cancer - including developing the cancer at a younger age.
– Professor Mark Baker, director of the Centre for Clinical Practice at Nice
It is also more likely that people with family members affected by cancer who then develop breast cancer themselves could develop a separate tumour in the other breast following initial treatment.
This is why it's wise for any person with a family history of cancer to receive appropriate investigations and screening that would otherwise be unnecessary if a family history did not exist.This guideline was last updated in 2006. Since then there has been new evidence published and new advances made in a number of clinical areas