Axillary staging in breast cancer patients with exclusive lymphoscintigraphic drainage to the internal mammary Chain

Background: The aim of this study was to evaluate the need of axillary staging in breast cancer patients showing exclusive lymphatic drainage to the internal mammary chain (IMC). Methods: A total of 2203 patients treated for breast carcinoma in three participating hospitals between July 2001 and July 2008 were analyzed. Only patients showing drainage to the IMC on preoperative lymphoscintigraphy were included. The number of harvested IMC sentinel lymph nodes (SLNs), axillary SLNs, and metastases were recorded. Finally, the follow-up of this group of patients was analyzed. Results: In 25/426 patients, drainage was exclusively to the IMC. Exploration of the axilla resulted in the harvesting of blue SLNs in 9 patients (36%) and the retrieval of an enlarged lymph node in 1 patient. In 4 of the remaining 15 patients, an axillary lymph node dissection (ALND) was done. Lymph node metastases were found in 3 patients who had blue axillary SLNs and in 1 patient who underwent ALND. In the 11 patients who had no blue SLNs and no ALND, no axillary recurrences were observed during follow-up (median = 26 months). Conclusions: Proper staging of the axilla remains crucial in patients showing exclusive drainage to the IMC. When no axillary node can be retrieved, ALND remains subject to discussion.