Discordance of intraoperative frozen section analysis with definitive histology of sentinel lymph nodes in breast cancer surgery: complementary axillary lymph node dissection is irrelevant for subsequent systemic therapy.

BACKGROUND: In breast cancer surgery, intraoperative frozen section (FS) analysis of sentinel lymph nodes (SLNs) enables axillary lymph node dissection (ALND) during the same operative procedure. In case of discordance between a "negative" FS analysis and definitive histology, an ALND as a second operation is advocated since additional lymph node metastases may be present. The clinical implications of the subsequent ALND in these patients were evaluated. MATERIALS AND METHODS: Between November 2000 and May 2008, 879 consecutive breast cancer patients underwent surgery including sentinel lymph node biopsy (SLNB) with intraoperative FS analysis of 2 central cuts from axillary SLNs. Following fixation and serial sectioning, SLNs were further examined postoperatively with hematoxylin and eosin (H&E) and immunohistochemical techniques. For patients with a discordant FS examination, the effect of the pathology findings of the subsequent ALND specimen on subsequent nonsurgical therapy were evaluated. RESULTS: FS analysis detected axillary metastases in the SLN(s) in 200 patients (23%), while the definitive pathology examination detected metastases in SLNs in another 151 patients (17%). A complementary ALND was performed in 108 of the 151 patients with discordant FS. Additional tumor positive axillary lymph nodes were found in 17 patients (16%), leading to "upstaging" in 7 (6%). Subsequent nonsurgical treatment was adjusted in 4 patients (4%): all 4 had more extensive locoregional radiotherapy; no patient received additional hormonal and/or chemotherapy. CONCLUSION: Discordance between intraoperative FS analysis and definitive histology of SLNs is common. In this selection of patients, a substantial proportion had additional lymph node metastases, but postsurgical treatment was rarely adjusted based on the findings of the complementary ALND.

The impact on post-surgical treatment of sentinel lymph node biopsy of internal mammary lymph nodes in patients with breast cancer.

BACKGROUND: Since the introduction of the sentinel lymph node (SLN) biopsy in breast cancer patients there is a renewed interest in lymphatic drainage to the internal mammary (IM) chain nodes. We evaluated the frequency of lymphatic drainage to the IM chain, the rate of SLNs that contain metastases and the clinical implications of IM LN metastases. METHODS: Between June 1999 and April 2005 506 consecutive patients underwent SLN biopsy as a staging procedure for clinically T1-2N0 breast cancer. In all patients preoperative lymphoscintigraphy was combined with the intraoperative use of a gammaprobe. In patients with IM SLNs visualized on lymphoscintigraphy, LNs were extirpated through an intercostal parasternal incision. RESULTS: SLNs were visualized by preoperative lymphoscintigraphy in 99% of all patients (502/506): axillary SLNs in 499 patients (99%), ipsilateral IM LNs in 109 patients (22%). In 85 patients with visualized IM SLNs the IM nodes could be removed (78%). In 20 of the latter 85 patients IM SLNs contained metastases (24%). IM metastases were associated with axillary LN metastases (P < 0.001). In 17 patients IM metastases led to extension of the radiotherapy field, while additional (adjuvant) systemic therapy was given in six patients. CONCLUSION: SLNs in the IM chain are common in breast cancer patients and can be extirpated in the majority of these patients. The proportion of patients in whom radiotherapeutic treatment was adjusted due to IM LN metastases was substantial. We advocate retrieval of IM SLNs when visualized by preoperative lymphoscintigraphy.