The antiproliferative effects of metformin were explored
in some clinical studies. A retrospective analysis of 2,529 early
stage breast cancer patients showed a higher rates of pathological
complete response after neoadjuvant chemotherapy
in diabetic women takingmetformin compared with those not
using metformin (24% vs. 8%, p .07) and in nondiabetic
women compared with diabetic patients not taking metformin
(16% vs. 8%, p .04). Moreover, metformin was identified
as an independent predictive factor of pathological
complete response [83].