Lymphatic drainage from peri-umbilical skin to internal mammary nodes.

While performing lymphoscintigraphy to define draining lymph node groups and sentinel nodes in patients with melanoma, the authors have discovered a new lymphatic channel in two patients with tumors in the peri-umbilical area. This channel passes over the right costal margin to an interval node before passing toward the midline, where it passes through the chest wall to reach the internal mammary lymph node chain. Appreciating the possible presence of this channel in patients with periumbilical lesions has important implications for the surgical management and follow-up of these patients.