Incidental positive internal mammary lymph nodes: a multiple international institutional investigation

The internal mammary lymph node is the second most frequent site of nodal metastasis. With an increase in breast free flap reconstruction utilization of the internal mammary vessels, identification of these internal mammary lymph node metastases will become more prevalent. A chart review documented 75 free transverse rectus abdominis myocutaneous flaps cases performed at Kaiser Bellflower from 1998 to 2004. Between March 2000 and January 2006 there were 157 autologous breast reconstructions (122 DIEP flaps, 10 GAP flaps, 15 SIEA flaps, 7 free transverse rectus abdominis flaps, and 1 SCIA flap) using internal mammary vessels as the recipient site at the Chang Gung Memorial Hospital. A literature review was conducted to survey the current protocols in the surgical, oncological, and radiological communities. A population of 232 patients with breast reconstruction via free flaps was identified. The age range was 29 to 65 years. With the exception of the five cases presented, no other incidence of positive internal mammary lymph nodes was identified. Failure to account for the status of the internal mammary lymph nodes may risk understaging and preclude appropriate treatment stratification. With more frequent utilization of the internal mammary vessels, discussions regarding breast reconstruction should take this new oncological focus into consideration.