Chylous leakeage is a well know complication reported in 1% to 3% of patients undergoing cervical neck dissection, mediastinal lymph node dissection, or gastric resection for cancer as well in breast cancer patients undergoing axillary lymph node dissection; most of these cases occurs on the left side. This complication seems to be mainly related to abnormalities of the thoracic duct anatomy or the subclavian duct leading to injury of an aberrant lymphatic channel trunk during level I-II ALND. Two case reports in breast cancer patients with left sided chylous leakage following level I-II ALND are reported; their diagnostic and therapeutic management is discussed with a literature review in order to update the diagnostic and therapeutic perspectives in this peculiar clinical setting.