Lymphatic mapping and sentinel lymph node biopsy for patients with local recurrence after breast-conservation therapy.

BACKGROUND: Local recurrence (LR) after breast-conservation therapy for breast cancer occurs in 10% to 15% of cases. A subset of these represents biologically aggressive disease, yet prognostic features for identifying this high-risk category are lacking. We hypothesized that lymphatic mapping and sentinel lymph node biopsy would provide useful information regarding dominant lymphatic drainage patterns of patients with LR.
METHODS: Breast cancer case records involving surgery for LR at the University of Michigan from 2002 to 2004 were reviewed. The lymphatic drainage patterns were compared with those of 117 patients who underwent mapping for primary breast cancer.
RESULTS: Fourteen LR cases were identified (10 with initial axillary lymph node dissection, 2 with initial sentinel lymph nodes, and 2 with no axillary surgery at the time of primary cancer treatment); lymphatic mapping was performed in 10. The sentinel lymph node identification rate was 90%, the median number of lymph nodes retrieved was 3, and no metastases were detected. Significantly more cases of nonipsilateral axillary sentinel node drainage were observed in mapping procedures performed for LR compared with those for primary breast cancer (67% vs. 15%; P = .001).
CONCLUSIONS: Lymphatic mapping is feasible in patients undergoing mastectomy for LR and is likely to identify aberrantly located sentinel lymph nodes that would otherwise be overlooked with a conventional completion mastectomy.