Cancer causes are 'complex and not fully known'

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.

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