Axillary dissection is required if there is confirmed axillary lymph node involvement detected by palpation, x-ray studies, or through sentinel node biopsy. It involves removal of lymph glands in the armpit. Lymph glands (nodes) are small bean shaped structures in the lymphatic system that act as a filter for bacterial infection or cancer cells. It is the common cause of armpit discomfort after surgery including pain in the upper arm, numbness and shoulder stiffness. It can also cause long term lymphedema (fluid swelling) in the upper limb in about 10-30% of patients.