Sentinel lymph node biopsy performed after neoadjuvant chemotherapy is accurate in patients with documented node-positive breast cancer at presentation.

BACKGROUND: The optimal strategy for incorporating lymphatic mapping and sentinel lymph node biopsy into the management of breast cancer patients receiving neoadjuvant chemotherapy remains controversial. Previous studies of sentinel node biopsy performed following neoadjuvant chemotherapy have largely reported on patients whose prechemotherapy, pathologic axillary nodal status was unknown. We report findings using a novel comprehensive approach to axillary management of node-positive-patients receiving neoadjuvant chemotherapy. METHODS: We evaluated 54 consecutive breast cancer patients with biopsy-proven axillary nodal metastases at the time of diagnosis that underwent lymphatic mapping with nodal biopsy as well as concomitant axillary lymph node dissection after receiving neoadjuvant chemotherapy. All cases were treated at a single comprehensive cancer center between 2001 and 2005. RESULTS: The sentinel node identification rate after delivery of neoadjuvant chemotherapy was 98%. Thirty-six patients (66%) had residual axillary metastases (including eight patients that had undergone resection of metastatic sentinel nodes at the time of diagnosis), and in 12 cases (31%) the residual metastatic disease was limited to the sentinel lymph node. The final, post-neoadjuvant chemotherapy sentinel node was falsely negative in three cases (8.6%). The negative final sentinel node accurately identified patients with no residual axillary disease in 17 cases (32%). CONCLUSIONS: Sentinel lymph node biopsy performed after the delivery of neoadjuvant chemotherapy in patients with documented nodal disease at presentation accurately identified cases that may have been downstaged to node-negative status and can spare this subset of patients (32%) from experiencing the morbidity of an axillary dissection.

Comprehensive axillary evaluation in neoadjuvant chemotherapy patients with ultrasonography and sentinel lymph node biopsy.

BACKGROUND: There is ongoing debate regarding the optimal sequence of sentinel lymph node (SLN) biopsy and neoadjuvant chemotherapy (CTX) for breast cancer. We report the accuracy of comprehensive pre-neoadjuvant CTX and post-neoadjuvant CTX axillary staging via ultrasound imaging, fine-needle aspiration (FNA) biopsy, and SLN biopsy. METHODS: From 2001 to 2004, 91 neoadjuvant CTX patients at the University of Michigan Comprehensive Cancer Center underwent axillary staging by ultrasonography, ultrasound-guided FNA biopsy, SLN biopsy, or a combination of these. RESULTS: Axillary staging was pathologically negative by pre-neoadjuvant CTX SLN biopsy in 53 cases (58%); these patients had no further axillary surgery. In 38 cases (42%), axillary metastases were confirmed at presentation by either ultrasound-guided FNA or SLN biopsy. These 38 patients underwent completion axillary lymph node dissection (ALND) after delivery of neoadjuvant CTX. Follow-up lymphatic mapping was attempted in 33 of these cases, and the SLN was identified in 32 (identification rate, 97%). One third of these cases were completely node negative on ALND. Residual metastatic disease was identified in 22 cases, and the SLN was falsely negative in 1 (4.5%). CONCLUSIONS: Patients receiving neoadjuvant CTX can have accurate axillary nodal staging by ultrasound-guided FNA or SLN biopsy. In cases of documented axillary metastasis at presentation, repeat axillary staging with SLN biopsy can document the post-neoadjuvant CTX nodal status. This strategy optimizes pre-neoadjuvant CTX and post-neoadjuvant CTX staging information by distinguishing the patients who are node negative at presentation from those who have been downstaged to node negativity and offers the potential for avoiding unnecessary ALNDs in both of these patient subsets.