Breast cancer is considered among the leading causes of mortality and in Mexico is the leading cause of death in women over 25 years. Current limitations in treatment are associated to late diagnosis of the disease. Application of bioimpedance measurements to differentiate mammographic findings has technical feasibility because the electrical conductivity of neoplastic tissue is different with respect to normal tissue. The aim of this study was to evaluate if EIS has enough sensitivity to differentiate specific breast tumor type in patients. Ten voluntary patients were measured by Lock in amplifier SR844 to determine bioimpedance changes at multiple frequencies associated to ductal and lobular breast cancer. Measurements were compared to bioimpedance values in healthy mamas mirrored from their tumoral position. The results indicate that the regional hypervascularity characteristic of lobular breast cancer appears to increase the bulk tissue conductivity at low frequencies, but not in ductal carcinoma in which cancer cells are distributed along ductal regions. EIS appears to be more sensitive to distinguish lobular cancer.