Observational, retrospective, cohort study of 508 randomly selected patients referred to a regional cancer genetics unit, using review of case notes to explore whether a simple clinical "3, 2, 1" family history rule could have been used to improve timely and appropriate referrals for genetic assessment. The 3, 2, 1 criteria are: three affected relatives with the same/associated cancers, across two generations, with at least one person affected age<50 years.