Lymphatic drainage of the breast

Last revised by Yoshi Yu on 11 Apr 2023

Lymphatic drainage of breast originates from breast lobules and flows through intramammary nodes and channels into a subareolar plexus, called Sappey’s plexus. From this plexus, lymphatic drainage takes place through three main routes that parallel venous tributaries. Lymphatics from the left breast ultimately drain via the thoracic duct into the angle of the left subclavian and internal jugular vein, while the right breast drains via the right lymphatic duct into the angle of the right subclavian and internal jugular vein.

  • axillary or lateral pathway

    • dominant pathway (receives >75% of lymph from breasts)

    • drains all quadrants of the breast, with higher proportion of drainage from lateral quadrants, especially the upper outer quadrant 9

    • drains directly or via Sappey's plexus to axillary nodes 

    • either runs around inferior border of pectoralis major to reach the pectoral group of lymph nodes or pass directly to the subscapular group

    • few channels from superior breast to the apical group sometimes interrupted by the infraclavicular group of lymph nodes 

  • internal mammary pathway

    • drains all quadrants of the breast, with higher proportion of drainage from medial quadrants, especially the lower inner quadrant 9

    • passes through the intercostal spaces and pectoralis major into parasternal/internal mammary lymph nodes

    • connections may lead across the median plane and hence to the contralateral breast

  • retromammary pathway

    • comes from the deeper portion of the breast

    • contributes to a minor pathway relative to the others 9

    • drains to the subclavicular plexus

Other pathways occur when usual channels are blocked in disease. Lymph may pass to the contralateral breast, cervical nodes, peritoneal cavity and liver through the diaphragm or through the rectus sheath.

Compared to non-palpable breast lesions, palpable breast lesions more frequently drain via the internal mammary pathway 9.

Axillary lymph nodes can be divided into surgical levels:

  • level 1: lying below pectoralis minor

  • level 2: lying behind pectoralis minor

  • level 3: lying between the upper border of pectoralis minor and lower border of the clavicle

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.