Lymphatic drainage of the breast

Lymphatic drainage of breast originates from breast lobules and flows into a subareolar plexus, called Sappey’s plexus. From this plexus, lymphatic drainage takes place through three main routes:

• axillary or lateral pathway
  • fed by Sappey’s Plexus, as well as by ducts satellite lymphatics and by most of the parenchymal lymphatics
  • this pathway runs around the inferior edge of the pectoralis major and reach the pectoral group of axillary nodes
• internal mammary pathway
  • originates from both the lateral and medial halves of the breast and passes through the pectoralis major; connections may lead across the median plane and hence to the contralateral breast
• retromammary pathway
  • comes from the posterior portion of the breast

Lymphatics may reach the sheath of the rectus abdominis and the subperitoneal and subhepatic plexuses.

Usually, axillary lymph nodes receive more than 75% of the lymph drained from the breast.