Blood group as a prognostic indicator in breast cancer.

A retrospective analysis of 1001 patients with invasive breast cancer showed a difference in survival between patients with different blood groups. Analysis of time from operation to local recurrence and to general recurrence reinforced this finding. The difference between blood groups became increasingly significant after accepted prognostic factors were allowed for. Patients at particularly high risk of early death or general recurrence were those with blood groups B and AB, those with group AB having a greater relative local recurrence rate.