Inclusion criteria will be a diagnosis of mammary neoplasms and plans to undergo an elective ALND of Berg´s levels I and II due to axillary metastasis determined preoperatively by core biopsy or evidence of metastasis in the SLNB in the intraoperative or in the differed analysis. Exclusion criteria will be chronic renal failure due to possible toxicity of gentamicin and patients undergoing a modified radical mastectomy.