Management of contralateral axillary sentinel lymph nodes detected on lymphoscintigraphy for breast cancer.

Background: Detection of a contralateral axillary sentinel lymph node (SLN) during lymphoscintigraphy for breast cancer is rare, and its significance and management are unclear. The purpose of this study was to review our experience and analyze our results together with similar patients in the literature to identify common characteristics and propose a management strategy.

Methods: A PubMed search was performed for articles describing patients in whom contralateral axillary drainage was identified on lymphoscintigraphy. Additionally, a chart review was performed of all patients who had lymphoscintigraphy for breast cancer at our institution.

Results: At our institution, two of 988 (0.3 %) consecutive patients were identified with contralateral axillary drainage on lymphoscintigraphy. Twenty-seven publications describing 105 patients with contralateral axillary drainage were found. This comprised our study group of 107 patients. Lymphoscintigraphy patterns varied depending on the history and type of prior surgery. A history of chest/axillary surgery was significantly associated with absence of an ipsilateral SLN (p < 0.05). This was observed in 84.2 % of patients with prior axillary lymph node dissection versus 33.3 % with prior SLN. Contralateral SLN biopsy was attempted in 85 patients (79.4 %); 22 (20.6 %) were positive for tumor. In 17 patients (15.9 %), the contralateral node was the only positive SLN.

Conclusions: These findings suggest that contralateral uptake on lymphoscintigraphy, though rare (0.2 %), is clinically significant and such nodes should undergo excision. Because contralateral uptake is significantly associated with prior chest/axillary surgery, routine lymphoscintigraphy should be considered in this group, as it has potential to change disease stage and management.