Technical outcomes of sentinel-lymph-node resection and conventional axillary-lymph-node dissection in patients with clinically node-negative breast cancer: results from the NSABP B-32 randomised phase III trial.
ABSTRACT The goals of axillary-lymph-node dissection (ALND) are to maximise survival, provide regional control, and stage the patient. However, this technique has substantial side-effects. The purpose of the B-32 trial is to establish whether sentinel-lymph-node (SLN) resection can achieve the same therapeutic goals as conventional ALND but with decreased side-effects. The aim of this paper is to report the technical success and accuracy of SLN resection plus ALND versus SLN resection alone.
5611 women with invasive breast cancer were randomly assigned to receive either SLN resection followed by immediate conventional ALND (n=2807; group 1) or SLN resection without ALND if SLNs were negative on intraoperative cytology and histological examination (n=2804; group 2) in the B-32 trial. Patients in group 2 underwent ALND if no SLNs were identified or if one or more SLNs were positive on intraoperative cytology or subsequent histological examination. Primary endpoints, including survival, regional control, and morbidity, will be reported later. Secondary endpoints are accuracy and technical success and are reported here. This trial is registered with the Clinical Trial registry, number NCT00003830.
Data for technical success were available for 5536 of 5611 patients; 75 declined protocol treatment, had no SLNs removed, or had no SLN resection done. SLNs were successfully removed in 97.2% of patients (5379 of 5536) in both groups combined. Identification of a preincision hot spot was associated with greater SLN removal (98.9% [5072 of 5128]). Only 1.4% (189 of 13171) of SLN specimens were outside of axillary levels I and II. 65.1% (8571 of 13 171) of SLN specimens were both radioactive and blue; a small percentage was identified by palpation only (3.9% [515 of 13 171]). The overall accuracy of SLN resection in patients in group 1 was 97.1% (2544 of 2619; 95% CI 96.4-97.7), with a false-negative rate of 9.8% (75 of 766; 95% CI 7.8-12.2). Differences in tumour location, type of biopsy, and number of SLNs removed significantly affected the false-negative rate. Allergic reactions related to blue dye occurred in 0.7% (37 of 5588) of patients with data on toxic effects.
The findings reported here indicate excellent balance in clinical patient characteristics between the two randomised groups and that the success of SLN resection was high. These findings are important because the B-32 trial is the only trial of sufficient size to provide definitive information related to the primary outcome measures of survival and regional control. Removal of more than one SLN and avoidance of excisional biopsy are important variables in reducing the false-negative rate.
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ABSTRACT: The study was to estimate the likelihood of axillary downstaging and to identify the factors predicting a pathologically node negative status after neoadjuvant chemotherapy (NAC) with or without trastuzumab in HER2-positive breast cancer. Patients with HER2-positive, stage IIa-IIIc breast cancer were enrolled. Axillary status was evaluated by palpation and fine needle aspiration (FNA) before NAC. All patients received 4-6 cycles of PCrb (paclitaxel 80 mg/m2 and carboplatin AUC = 2 d1, 8, and 15 of a 28-day cycle, or paclitaxel 175 mg/m2 and carboplatin AUC = 6 every-3-week) and were non-randomly administered trastuzumab (2 mg/kg weekly or 6 mg/kg every-3-week) or not. After NAC, each patient underwent standard axillary lymph node dissection and breast-conserving surgery or mastectomy. And some patients received sentinel lymph node biopsy (SLNB) before axillary dissection. Between November-2007 and June-2013, 255 patients were enrolled. Of them, 157 were confirmed as axillary node positive by FNA (group-A) and 98 as axillary node negative either by FNA or impalpable (group-B). After axillary dissection, the overall pathologically node negative rates (pNNR) were 52.9% in group-A and 69.4% in group-B. The ER-poor/HER2-positive subtype acquired the highest pNNR (79.6% in group-A and 87.9% in group-B, respectively) and the lowest rate of residual with ≥4 nodes involvement (1.9% and 3%, respectively) after PCrb plus trastuzumab. In multivariate analysis, trastuzumab added and ER-poor status were independent factors in predicting a higher pNNR in HER2-positive breast cancer. Forty-six tested patients showed that the ER-poor/HER2-positive subtype acquired a considerable high pNNR and axillary status with SLNB was well macthed with the axillary dissection. ER-poor/HER2-positive subtype of breast cancer is a potential candidate for undergoing sentinel lymph node biopsy instead of regional node dissection for accurate axillary evaluation after effective downstaging by neoadjuvant chemo-trastuzumab therapy.PLoS ONE 12/2014; 9(12):e114646. DOI:10.1371/journal.pone.0114646 · 3.53 Impact Factor
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ABSTRACT: Breast cancer staging with sentinel lymph node biopsy relies on the use of radioisotopes, which limits the availability of the procedure worldwide. The use of a magnetic nanoparticle tracer and a handheld magnetometer provides a radiation-free alternative, which was recently evaluated in two clinical trials. The hydrodynamic particle size of the used magnetic tracer differs substantially from the radioisotope tracer and could therefore benefit from optimization. The aim of this study was to assess the performance of three different-sized magnetic nanoparticle tracers for sentinel lymph node biopsy within an in vivo porcine model. Sentinel lymph node biopsy was performed within a validated porcine model using three magnetic nanoparticle tracers, approved for use in humans (ferumoxytol, with hydrodynamic diameter d H =32 nm; Sienna+(®), d H =59 nm; and ferumoxide, d H =111 nm), and a handheld magnetometer. Magnetometer counts (transcutaneous and ex vivo), iron quantification (vibrating sample magnetometry), and histopathological assessments were performed on all ex vivo nodes. Transcutaneous "hotspots" were present in 12/12 cases within 30 minutes of injection for the 59 nm tracer, compared to 7/12 for the 32 nm tracer and 8/12 for the 111 nm tracer, at the same time point. Ex vivo magnetometer counts were significantly greater for the 59 nm tracer than for the other tracers. Significantly more nodes per basin were excised for the 32 nm tracer compared to other tracers, indicating poor retention of the 32 nm tracer. Using the 59 nm tracer resulted in a significantly higher iron accumulation compared to the 32 nm tracer. The 59 nm tracer demonstrated rapid lymphatic uptake, retention in the first nodes reached, and accumulation in high concentration, making it the most suitable tracer for intraoperative sentinel lymph node localization.International Journal of Nanomedicine 01/2015; 10:1235-43. DOI:10.2147/IJN.S76962 · 4.20 Impact Factor
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ABSTRACT: Sentinel lymph node biopsy (SNB)-oriented stepwise treatment under local anesthesia has been performed in the outpatient-ambulatory setting in patients receiving neoadjuvant therapy (NAT). We retrospectively reviewed our preliminary experience of ambulatory SNB in breast cancer patients scheduled to undergo NAT to evaluate the usefulness and feasibility of this method as a minimally invasive, stepwise treatment protocol. We retrospectively identified 56 patients with breast cancer without obvious nodal involvement who were scheduled to receive NAT before breast surgery. SNB was performed under local anesthesia in an ambulatory outpatient setting before the initiation of NAT. The average number of removed sentinel lymph nodes was 1.9. Identification of the sentinel node was possible in all cases, and macrometastasis was observed in six cases (10.7%). Micrometastasis was observed in five cases, while isolated tumor cells were noted in six cases. There were no delays in the initiation of NAT as a result of complications of SNB. This pilot study demonstrated the safety and feasibility of ambulatory SNB prior to NAT. Further studies are warranted to assess the strict indications, patient satisfaction, and medical economics of this procedure.World Journal of Surgical Oncology 12/2015; 13(1). DOI:10.1186/s12957-015-0471-3 · 1.20 Impact Factor