Internal mammary lymph nodes and sentinel node biopsy in breast cancer

The long-term follow-up of patients treated with extended radical mastectom y has proved that the internal mammary node (IMN) status is an important pr ognosticator of breast cancer. Patients with isolated IMN involvement seem to have the same outcome as those with limited axillary disease, and these patients may therefore be overstaged in the TNM system. Sentinel node biops y (SNB) of IMNs may be an ideal staging procedure, but lymphatic mapping st udies demonstrate that data from extended radical mastectomy series cannot be extrapolated to patients suitable for SNB, where the IMN involvement is < 5% overall, and around 1% for IMN metastases without axillary disease. Cu rrent evidence does not allow internal mammary SNB to be recommended as a s tandard procedure, but as patients with IMN involvement may benefit from ad juvant systemic treatment, internal mammary SNB should be further studied i n this context. (C) 2001 Elsevier Science Ltd. All rights reserved.