Sentinel lymph node biopsy after neoadjuvant chemotherapy for advanced breast cancer: results of Ganglion Sentinelle et Chimiotherapie Neoadjuvante, a French prospective multicentric study

Targeted axillary dissection after neoadjuvant chemotherapy for highly selective patients with initial cN1 breast cancer: A single-center prospective trial

BACKGROUND

Sentinel lymph node (SLN) biopsy is gradually accepted as the standard of care in breast cancer patients with down-staged axillary disease after neoadjuvant chemotherapy (NAC). However, it is still difficult to precisely define pre-NAC clinical node-positive (cN1) and post-NAC clinical node-negative (ycN0). This prospective single-center trial was designed to evaluate the feasibility and accuracy of standard targeted axillary dissection (TAD) after NAC in highly selective pre-NAC cN1 patients (not considering ultrasound-based axillary ycN staging).

METHODS

This prospective trial included patients with initial pre-NAC cT1-3N1M0 invasive breast cancer but with a rigorous definition of cN1 from the Affiliated Cancer Hospital of Zhengzhou University. When NAC was effective (including complete and partial responses) and preoperative axillary palpation was negative, preoperative ultrasound-based axillary staging was not considered, and all patients underwent TAD followed by axillary lymph node (LN) dissection. The detection rate (DR) and false-negative rate (FNR) of TAD were calculated.

RESULTS

A total of 82 patients were included, and 77 of them were eligible for data analysis. The DR for TAD was 94.8% (73/77). There were 26 patients with one abnormal LN at the time of diagnosis based on ultrasound, 45 patients with two, and 2 patients with three. One patient had one TAD LN, four patients had two TAD LNs, and 68 patients had three or more TAD LNs. Preoperative axillary palpation yielded negative results for all 73 patients who successfully underwent TAD. Preoperative ultrasound-based ycN0 and ycN+ conditions were detected for 52 and 21 cases, respectively. The FNR was 7.4% (2/27) for standard TAD (≥3 SLNs), which was lower than that of all successful TAD (≥1 SLN; 10.0%, 3/30).

CONCLUSIONS

In rigorously defined pre-NAC cN1 breast cancer patients, standard TAD is feasible for those with negative axillary palpation after NAC, and FNR is also less than 10%.

REGISTRATION

chictr.org.cn , ChiCTR2100049093.

Assessing the Efficacy of Radioactive Iodine Seed Localisation in Targeted Axillary Dissection for Node-Positive Early Breast Cancer Patients Undergoing Neoadjuvant Systemic Therapy: A Systematic Review and Pooled Analysis

Targeted axillary dissection (TAD), employing marked lymph node biopsy (MLNB) alongside sentinel lymph node biopsy (SLNB), is increasingly recognised for its efficacy in reducing false negative rates (FNRs) in node-positive early breast cancer patients receiving neoadjuvant systemic therapy (NST). One such method, 125I radioactive seed localisation (RSL), involves implanting a seed into a biopsy-proven lymph node either pre- or post-NST. This systematic review and pooled analysis aimed to assess the performance of RSL in TAD among node-positive patients undergoing NST. Six studies, encompassing 574 TAD procedures, met the inclusion criteria. Results showed a 100% successful deployment rate, with a 97.6% successful localisation rate and a 99.8% retrieval rate. Additionally, there was a 60.0% concordance rate between SLNB and MLNB. The FNR of SLNB alone was significantly higher than it was for MLNB (18.8% versus 5.3%, respectively; p = 0.001). Pathological complete response (pCR) was observed in 44% of cases (248/564). On average, the interval from 125I seed deployment to surgery was 75.8 days (range: 0-272). These findings underscore the efficacy of RSL in TAD for node-positive patients undergoing NST, enabling precise axillary pCR identification and facilitating the safe omission of axillary lymph node dissection.

The Feasibility and Reliability of Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy in Breast Cancer Patients With Negative Axillary Lymph Nodes-A Meta-analysis

Background

The application of sentinel lymph node biopsy (SLNB) has expanded from early breast cancer to locally advanced breast cancer with neoadjuvant chemotherapy (NAC). For patients with negative axillary lymph nodes, performing SLNB before or after NAC remains controversial.

Objectives

To evaluate the diagnostic feasibility and reliability of SLNB after NAC in breast cancer patients with negative axillary nodes at initial diagnosis.

Design

To calculate pooled identification rate (IR) and false negative rate (FNR) of SLNB after NAC on breast cancer patients with initially negative axillary nodes by enrolling relevant studies and perform subgroup analysis by the type of tracer and the number of biopsied sentinel lymph nodes in average.

Data sources and methods

The PubMed, Embase, Cochrane, Web of Science, and Scopus databases from January 1, 2002, to March 1, 2022, were searched for studies. The QUADAS-2 tool and MINORS item were employed to evaluate the quality of the included studies. I2 and Q tests were used to evaluate the heterogeneity among the studies. Random-effects model and fixed-effects model were employed to calculate the pooled IR, FNR, and 95% confidence interval (CI). Publication bias was evaluated, and sensitivity analysis was performed. Subgroup analysis was performed according to the type of tracer (single/double) and the number of biopsied sentinel lymph nodes in average (⩽2/>2).

Results

A total of 21 studies covering 1716 patients were enrolled in this study (IR = 93%, 95% CI = 90-96; FNR = 8%, 95% CI = 6-11).

Conclusion

The SLNB after NAC can serve as a feasible and reliable approach in breast cancer patients with negative axillary lymph node. In our study, no significant impact of tracer was found on the IR and FNR of SLNB, and the number of biopsy nodes >2 leads to the decreased FNR of SLNB.

[Can we avoid axillary lymph node dissection in patients with node positive invasive breast carcinoma?]

OBJECTIVES

The indications and modalities of breast and axillary surgery are undergoing profound change, with the aim of personalizing surgical management while avoiding over-treatment. To update best practices for axillary surgery, four questions were selected by the Senology Commission of the Collège National des Gynécologues et Obstétriciens Français (CNGOF), focusing on, firstly, the definition and evaluation of targeted axillary dissection (TAD) techniques; secondly, the possibility of surgical de-escalation in case of initial lymph node involvement while performing initial surgery; thirdly, in case of surgery following neo-adjuvant systemic therapy (NAST), and fourthly, contra-indications to de-escalation of axillary surgery to allow access to particular adjuvant systemic therapies.

METHODS

The Senology Commission based its responses primarily on an analysis of the international literature, clinical practice recommendations and national and international guidelines.

RESULTS

Firstly, TAD is a technique that combines excision of clipped metastatic axillary node(s) and the axillary sentinel lymph nodes (ASLNs). The detection rate and sensitivity are increased but it still needs to be standardized and practices better evaluated. Secondly, TAD represents an alternative to axillary clearance in cases of metastatic involvement of a single node that can be resected. Thirdly, neither TAD nor ASLN alone is recommended in France after NAST outside of clinical trials, although it is used in several countries in cases of complete pathological response in the lymph nodes, and when at least three lymph nodes have been removed. Fourthly, as some adjuvant targeted therapies are indicated in cases of lymph node invasion of more than three lymph nodes, the place of TAD in this context remains to be defined.

CONCLUSION

Axillary surgical de-escalation can limit the morbidity of axillary clearance. Having proved that TAD does not reduce patient survival, it will most probably replace axillary clearance in well-defined indications. This will require prior standardization of the method and its indications and contra-indications, particularly to enable the use of new targeted therapies.

Magnetically guided surgery after primary systemic therapy for breast cancer: implications for enhanced axillary mapping

BACKGROUND

Superparamagnetic iron nanoparticles perform comparably to radioisotope ± blue dye for sentinel lymph node detection in breast cancer, even when injected up to 8 weeks before surgery. Using superparamagnetic iron nanoparticles for sentinel lymph node detection after primary systemic therapy, and the maximum time frame of superparamagnetic iron nanoparticle administration have not been investigated.

METHODS

This cohort study included cN0/1-to-ycN0 patients undergoing sentinel lymph node detection or targeted axillary dissection. All patients received superparamagnetic iron nanoparticles either before primary systemic therapy or before surgery, and radioisotope on the day of surgery.

RESULTS

For 113 patients analysed, superparamagnetic iron nanoparticles were injected a median of 3 (range 0-248) days before surgery, with a 97.4% detection rate compared with 91.2% for radioisotope (P = 0.057). Concordance for radioisotope was 97.1% and this was not affected by timing of superparamagnetic iron nanoparticle injection (Kendall's tau 0.027; P = 0.746). The median sentinel lymph node yield was 3 (interquartile range (i.q.r.) 2-3) for superparamagnetic iron nanoparticles and 2 (i.q.r. 2-3) for radioisotope (P < 0.001). In targeted axillary dissection, detection was 100% for superparamagnetic iron nanoparticles and 81.8% for radioisotope (P = 0.124). The index node was magnetic in 93.9% and radioactive in 66.7% (P = 0.007), an outcome that was not affected by any factors. For patients with metastases, superparamagnetic iron nanoparticle detection was 100% and radioisotope-based detection was 84.2% (P = 0.083), with superparamagnetic iron nanoparticles detecting more metastatic sentinel lymph nodes (median of 1 (i.q.r. 1-2) for superparamagnetic iron nanoparticles compared with a median of 1 (i.q.r. 0-1) for radioisotope; P = 0.005).

CONCLUSION

Injection before primary systemic therapy is feasible and does not affect concordance with radioisotope. Superparamagnetic iron nanoparticles perform comparably to radioisotope, but detect more sentinel lymph nodes and have a higher rate of detection of metastatic sentinel lymph nodes.

A Survey of Practice Patterns for Clinical Nodal Staging Prior to Neoadjuvant Chemotherapy in Breast Cancer

BACKGROUND

The importance of clinical staging in breast cancer has increased owing to the wide use of neoadjuvant systemic therapy (NST). This study aimed to investigate the current practice patterns regarding clinical nodal staging in breast cancer in real-world settings.

MATERIALS AND METHODS

A web-based survey was administered to board-certified oncologists in Korea, including breast surgical, medical, and radiation oncologists, from January to April 2022. The survey included 19 general questions and 4 case-based questions.

RESULTS

In total, 122 oncologists (45 radiation, 44 surgical, and 33 medical oncologists) completed the survey. Among them, 108 (88%) responded that clinical staging before NST was primarily performed by breast surgeons. All the respondents referred to imaging studies during nodal staging. Overall, 64 (52.5%) responders determined the stage strictly based on the radiology reports, whereas 58 (47.5%) made their own decision while noting radiology reports. Of those who made their own decisions, 88% referred to the number or size of the suspicious node. Of the 75 respondents involved in prescribing regimens for neoadjuvant chemotherapy, 58 (77.3%) responded that the reimbursement regulations in the selection of NST regimens affected nodal staging in clinical practice. In the case-based questions, high variability was observed among the clinicians in the same cases.

CONCLUSIONS

Diverse assessments by specialists owing to the lack of a clear, harmonized staging system for the clinical nodal staging of breast cancer can lead to diverse practice patterns. Thus, practical, harmonized, and objective methods for clinical nodal staging and for the outcomes of post-NST response are warranted for appropriate treatment decisions and accurate outcome evaluation.

Evidence-Based Strategies to Minimize the Likelihood of Axillary Lymph Node Dissection in Clinically Node-Positive Patients Following Neoadjuvant Chemotherapy

De-escalation of axillary management after neoadjuvant chemotherapy in clinically node-positive patients is feasible. The current literature shows this may be accomplished by sentinel lymph node biopsy (SLNB) with the use of dual tracer and removal of at least 2 sentinel lymph nodes, or by targeted axillary dissection (TAD). The accuracy of TAD has been consistently shown as better than that of SLNB. However, these techniques should only be offered to select patients without extensive axillary disease, understanding that long-term outcomes of minimal axillary surgery in this population are limited at this time.

Axillary pathologic response after neoadjuvant chemotherapy and surgery according to breast cancers subtypes and survival impact

PURPOSE

To retrospectively assess the rate of pathologic complete response in the axilla according to breast cancer biologic subtypes, and to study the impact of nodal response on survival.

METHODS

Inclusion criteria were all T-stage breast cancers with initial lymph node involvement, non-metastatic, treated with neoadjuvant chemotherapy followed by surgery with axillary lymph node dissection, managed at the George-François Leclerc Cancer Center in Dijon, France, between 2000 and 2018.

RESULTS

Among 437 patients included, the rate of complete nodal response rate varied according to tumor subtypes: 69.4% in Hormone Receptors (HR)-/HER2-positive, 47.4% in HR-/HER2-negative, 46.7% in HR+/HER2-positive, 8.5% in HR+/HER2-negative. By multivariate analysis, the factors significantly associated with complete nodal response were HER2-positive profile (OR 4.48 [2.14-9.65], P<0.001 if HR+; OR 8.02 [3.54-18.74], P<0.001 if HR-), triple negative tumors (OR 3.01 [1.40-6.58], P=0.005), SBRIII grade (OR 6.85 [2.28-29.58], P=0.002) and breast complete response (OR 18.69 [9.67-38.53], P<0.001). Five-year recurrence rates were 15.7% in ypN0, 23% in ypN1, 41.2% in ypN2, 50% in ypN3 patients (P<0.001). Five-year overall survival rates were 92.2% in ypN0, 85.7% in ypN1, 72.2% in ypN2, 65.4% in ypN3 patients (P<0.001).

CONCLUSION

The impact of nodal response on survival was significant. Pathologic complete response in the axilla appears to be a good surrogate marker of long-term outcome in patients treated for these cancers.

Regional radiotherapy after primary systemic treatment for cN+ breast cancer patients

Pathologic complete response (pCR) after Primary Systemic Treatment (PST) for breast cancer is associated with excellent long-term outcomes. With increasing use of PST, the indication for regional nodal irradiation (RNI) has been challenged. The aim of this paper is to review the literature on de-escalation of RNI in patients treated with PST. We found no level 1 evidence on de-escalation of RNI after PST, but several randomized trials are ongoing. Consequently, current de-escalation strategies are based on cohort studies. These studies showed that in patients with low nodal tumour burden (LNTB) (≤3 suspicious nodes at imaging) prior to PST, and ypN0 based on Axillary Lymph Node Dissection (ALND), omission of RNI resulted in very low regional recurrences (RR) without compromising survival. In patients with LNTB and ypN0 based on Sentinel Lymph Node Biopsy (SLNB), omission of axillary treatment also resulted in low RR; the majority of these patients received local radiotherapy. Similarly, in patients with ypN1 (ALND) disease, omission of RNI resulted in low 5-year RR rates. Low RR-rates were also found in the few studies replacing ALND by RNI, in patients with ypN1 (SLNB) disease. In patients with high nodal tumour burden prior to PST and ypN0 (SLNB), replacing ALND by RNI also resulted in low RR. Due to the limited number of patients, these data should be interpreted with caution. We conclude that although level 1 evidence is lacking, de-escalation of RNI after PST can be considered in selected cases.

Omission of axillary lymph node dissection in patients with ypN+ breast cancer after neoadjuvant chemotherapy: A retrospective multicenter study (KROG 21-06)

BACKGROUND

We evaluated the impact of omitting axillary lymph node dissection (ALND) on oncological outcomes in breast cancer patients with residual nodal disease after neoadjuvant chemotherapy (NAC).

METHODS

The medical records of patients who underwent NAC followed by surgical resection and had residual nodal disease were retrospectively reviewed. In total, 1273 patients from 12 institutions were included; all underwent postoperative radiotherapy. Axillary surgery consisted of ALND in 1103 patients (86.6%) and sentinel lymph node biopsy (SLNBx) alone in 170 (13.4%). Univariate and multivariate analyses of disease-free survival (DFS) and overall survival (OS) were performed before and after propensity score matching (PSM).

RESULTS

The median follow-up was 75.3 months (range, 2.5-182.7). Axillary recurrence rates were 4.8% in the ALND group (n = 53) and 4.7% in the SLNBx group (n = 8). Before PSM, univariate analysis indicated that the 5-year OS rate was inferior in the ALND group compared to the SLNBx group (86.6% vs. 93.3%, respectively; P = 0.002); multivariate analysis did not show a difference between groups (P = 0.325). After PSM, 258 and 136 patients were included in the ALND and SLNBx groups, respectively. There were no significant differences between the ALND and SLNBx groups in DFS (5-year rate, 75.8% vs. 76.9%, respectively; P = 0.406) or OS (5-year rate, 88.7% vs. 93.1%, respectively; P = 0.083).

CONCLUSIONS

SLNBx alone did not compromise oncological outcomes in patients with residual nodal disease after NAC. The omission of ALND might be a possible option for axillary management in patients treated with NAC and postoperative radiotherapy.

Estimating the Benefit of Preoperative Systemic Therapy to Reduce the Extent of Breast Cancer Surgery: Current Standard and Future Directions

Once reserved for locally advanced tumors which were deemed inoperable at presentation, preoperative systemic therapy (PST) is nowadays increasingly used to treat early breast cancer. PST allows for in vivo assessment of tumor response, for tailoring of adjuvant systemic therapy and for de-escalation of breast and the axillary surgery. Increased rates of pathological complete response together with more accurate response assessment and surgical planning have led to a significant reduction in surgical morbidity. While surgical assessment remains the standard of care, ongoing studies are evaluating whether surgery can be omitted in patients who achieve a complete pathological response. In this chapter, I will review the impact of PST on surgical de-escalation and the data supporting the safety of this approach.

A Model Incorporating Axillary Tail Position on Mammography for Preoperative Prediction of Non-sentinel Lymph Node Metastasis in Patients with Initial cN+ Breast Cancer after Neoadjuvant Chemotherapy

RATIONALE AND OBJECTIVES

This study aimed to develop a model incorporating axillary tail position on mammography (AT) for the prediction of non-sentinel Lymph Node (NSLN) metastasis in patients with initial clinical node positivity (cN+).

METHODS AND MATERIALS

The study reviewed a total of 257 patients with cN+ breast cancer who underwent both sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) following neoadjuvant chemotherapy (NAC). A logistic regression model was developed based on these factors and the results of post-NAC AT and axillary ultrasound (AUS).

RESULTS

Four clinical factors with p<0.1 in the univariate analysis, including ycT0(odds ratio [OR]: 4.84, 95% confidence interval [CI]: 2.13-11.91, p<0.001), clinical stage before NAC (OR: 2.68, 95%CI: 1.15-6.58, p=0.025), estrogen receptor (ER) expression (OR: 3.29, 95%CI: 1.39-8.39, p=0.009), and HER2 status (OR: 0.21, 95%CI: 0.08-0.50, p=0.001), were independent predictors of NSLN metastases. The clinical model based on the above four factors resulted in the area under the curve (AUC) of 0.82(95%CI: 0.76-0.88) in the training set and 0.83(95% CI: 0.74-0.92) in the validation set. The results of post-NAC AUS and AT were added to the clinical model to construct a clinical imaging model for the prediction of NSLN metastasis with AUC of 0.87(95%CI: 0.81-0.93) in the training set and 0.89(95%CI: 0.82-0.96) in the validation set.

CONCLUSIONS

The study incorporated the results of post-NAC AT and AUS with other clinal factors to develop a model to predict NSLN metastasis in patients with initial cN+ before surgery. This model performed excellently, allowing physicians to select patients for whom unnecessary ALND could be avoided after NAC.

Diagnostic accuracy of de-escalated surgical procedure in axilla for node-positive breast cancer patients treated with neoadjuvant systemic therapy: A systematic review and meta-analysis

BACKGROUND

More initial clinical node-positive breast cancer patients achieve axillary pathological complete response (ax-pCR) after neoadjuvant systemic therapy (NST). Restaging axillary status and performing de-escalated surgical procedures to replace routine axillary lymph nodes dissection (ALND) is urgently needed. Targeted axillary lymph node biopsy (TLNB) is a novel de-escalated surgical strategy marking metastatic axillary nodes before NST and targeted dissection and biopsy intraoperatively to tailor individual axillary management.

METHODS

This study provided a systematic review and meta-analysis to evaluate the feasibility and diagnosis accuracy of TLNB. Prospective and retrospective clinical trials on TLNB were searched from Pubmed, Embase, and Cochrane. Identification rate (IFR), false-negative rate (FNR), negative predictive value (NPV), and rate of ax-pCR were the outcomes of this meta-analysis.

RESULTS

One thousand nine hundred and twenty patients attempted TLNB, with an overall IFR of 93.5% (95% confidence interval [CI] 90.1%-96.2%). IFR of three nodal marking methods, namely iodine seeds, clips, and carbon dye, was 95.6% (95% CI 91.2%-98.7%), 91.7% (95% CI 87.3%-95.4%), and 97.1% (95% CI 89.1%-100.0%), respectively. Of them, 847 patients received ALND, with an overall FNR of 5.5% (95% CI 3.3%-8.0%), and NPV ranged from 90.1% to 96.1%. Regression analysis showed that the overlap of targeted and sentinel biopsied nodes might associate with IFRs and FNRs.

CONCLUSION

TLNB is a novel, less invasive surgical approach to distinguish initial node-positive breast cancer that achieves negative axillary conversion after NST. It yields an excellent IFR with a low FNR and a high NPV. A combination of preoperative imaging, intraoperative TLNB with SLNB, and postoperative nodal radiotherapy might affect the future treatment paradigm of primary breast cancer with nodal metastases.

Feasibility of Magnetic Technique for Axillary Staging after Neoadjuvant Therapy in Breast Cancer Patients

PURPOSE

Optimal axillary staging after neoadjuvant chemotherapy (NAC) in node-negative breast cancer is an area of controversy. Sentinel node biopsy with Technetium-sulphur colloid (99m Tc) alone or with blue dye is the recommended technique for evaluating axilla in these patients. However, this technique has drawbacks such as limited access to nuclear departments and timing limitations related to Tc injection exposing patients to unnecessary radiation. Superparamagnetic iron oxide nanoparticles (SPIO) may represent a valid option for SLN biopsy. In this study, we assessed the feasibility of the magnetic technique (Sentimag) with combination of isosulfan blue dye in breast cancer patients who received NAC.

METHODS

The study sample consisted of 54 female breast cancer patients who received NAC. Sentinel node localization was performed using magnetic technique and blue dye. Sentinel node identification rate (IFR) of magnetic technique was calculated and postoperative complications were assessed.

RESULTS

Sentinel lymph node was detected in 52 patients with Sentimag method (identification rate = 96.3%, 95% CI: 87.4-98.9%). Blue dye was successful to find SLN in 38 patients (identification rate = 70%). The most common histologic type was invasive ductal (n = 51; 94.4%). Mean tumor size was 2.1 cm after NAC. Most of patients had T2 (n = 30; 55.5%) and HER2 + positive (n = 49; 90.7%) cancer.

CONCLUSION

Sentimag which is a magnetic technique appears to be safe, easy to perform with minimal adverse effects, may be an alternative and accurate technique in patients with NAC, especially in breast units where nuclear medicine unit is not available.

Supplemental data for this article is available online at https://doi.org/10.1080/08941939.2022.2038737 .

A Propensity Score Matched Analysis of Superparamagnetic Iron Oxide versus Radioisotope Sentinel Node Biopsy in Breast Cancer Patients after Neoadjuvant Chemotherapy

The standard method for nodal staging in breast cancer (BC) patients after neoadjuvant chemotherapy (NAC) is sentinel lymph node biopsy (SLNB) with a radioisotope (RI) injection. However, SLNB after NAC results in high false-negative rates (FNR), and the RI method is restricted by nuclear medicine unit dependency. These limitations resulted in the development of the superparamagnetic iron oxide (SPIO) method, reducing FNR and presenting a comparable detection rate. This bi-institutional cohort comparison study aimed to assess the efficacy of SPIO and radioisotope SNLB in BC patients after NAC using Propensity Score Matching (PSM) analysis. The study group comprised 508 patients who underwent SLNB after NAC for ycT1-4N0M0 BC between 2013 and 2021 in two high volume centers. Data were retrieved from prospectively conducted databases. In the SPIO group, the median of retrieved sentinel lymph nodes (SLNs) was significantly higher than in the RI group (3 vs. 2; p < 0.0001). The SPIO method was associated with a significantly higher chance of retrieving at least three lymph nodes when compared to the RI method (71% vs. 11.3%; p < 0.0001). None of the analyzed demographic and clinical variables had a statistically significant influence on the efficacy of SLNs retrieval in the RI group, while in the SPIO group, patients with ≥three harvested SLNs had lower weight and decreased BMI. Based on this PSM analysis, SPIO-guided SLNB allowed the efficient retrieval and detection of SLNs in BC patients after NAC compared to RI.

A Propensity Score Matched Analysis of Superparamagnetic Iron Oxide versus Radioisotope Sentinel Node Biopsy in Breast Cancer Patients after Neoadjuvant Chemotherapy

Simple Summary

This Propensity Score Matched Analysis aimed to assess the efficacy of superparamagnetic iron oxide (SPIO) and radioisotope sentinel lymph node biopsy (SNLB) in breast cancer (BC) patients after neoadjuvant chemotherapy (NAC). One hundred and twenty-four patients were eligible for final analysis. In the SPIO group, the median of retrieved sentinel lymph nodes (SLNs) was significantly higher than in the RI group. The SPIO method was associated with a significantly higher chance of retrieving at least three SLNs when compared to the RI method. SPIO-guided SLNB allows efficient retrieval and detection of SLNs in BC patients after NAC when compared to RI.

Abstract

The standard method for nodal staging in breast cancer (BC) patients after neoadjuvant chemotherapy (NAC) is sentinel lymph node biopsy (SLNB) with a radioisotope (RI) injection. However, SLNB after NAC results in high false-negative rates (FNR), and the RI method is restricted by nuclear medicine unit dependency. These limitations resulted in the development of the superparamagnetic iron oxide (SPIO) method, reducing FNR and presenting a comparable detection rate. This bi-institutional cohort comparison study aimed to assess the efficacy of SPIO and radioisotope SNLB in BC patients after NAC using Propensity Score Matching (PSM) analysis. The study group comprised 508 patients who underwent SLNB after NAC for ycT1-4N0M0 BC between 2013 and 2021 in two high volume centers. Data were retrieved from prospectively conducted databases. In the SPIO group, the median of retrieved sentinel lymph nodes (SLNs) was significantly higher than in the RI group (3 vs. 2; p < 0.0001). The SPIO method was associated with a significantly higher chance of retrieving at least three lymph nodes when compared to the RI method (71% vs. 11.3%; p < 0.0001). None of the analyzed demographic and clinical variables had a statistically significant influence on the efficacy of SLNs retrieval in the RI group, while in the SPIO group, patients with ≥three harvested SLNs had lower weight and decreased BMI. Based on this PSM analysis, SPIO-guided SLNB allowed the efficient retrieval and detection of SLNs in BC patients after NAC compared to RI.

How Often Does Retrieval of a Clipped Lymph Node Change Adjuvant Therapy Recommendations? A Prospective, Consecutive, Patient Cohort Study

BACKGROUND

Prior studies examining sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) for cN1 patients have demonstrated that 20% of biopsied, clipped lymph nodes (cLNs) are nonsentinel lymph nodes (non-SLNs). Our goal was to determine how often the cLN was a non-SLN among both cN0 and cN1 patients and how often cLN pathology impacted management.

METHODS

Overall, 238 patients treated with NAC and surgery January 2019 to June 2020 were prospectively examined. Patients underwent routine axillary ultrasound, biopsy of suspicious nodes, and clip placement. Radioactive iodine-125 seed localization of the cLN was performed in cN1 patients only. Isolated tumor cells (ITCs) were considered node positive (ypN+) for both cN0 and cN1 cohorts. Chart review was performed to determine if cLNs were non-SLN and their ypN status.

RESULTS

Of 118 cN0 patients, 115 of 118 (97%) underwent successful SLNB, 33 of whom had a cLN present; 21 of 33 (64%) cLNs were non-SLNs. Overall, 9 of 118 (8%) were ypN+; no cLN was ypN+ without additional +SLNs. Of 120 cN1 patients, 104 of 120 (87%) converted to cN0, 98 of 104 (94%) of which had attempted SLNB, and 95 of 98 (97%) successfully mapped. The cLN was a non-SLN in 18 of 95 (19%). Overall, 58 of 104 (56%) cN1 patients were ypN+. One patient had a positive cLN in the absence of +SLNs. This patient underwent axillary lymph node dissection (ALND); adjuvant treatment recommendations were unchanged.

CONCLUSIONS

The cLN was a non-SLN in 19% of cN1 patients. cLN pathology did not impact adjuvant therapy recommendations, calling into question the utility of routinely clipping biopsied lymph nodes.

Outcomes of Sentinel Node Biopsy for Women with Breast Cancer After Neoadjuvant Therapy: Systematic Review and Meta-Analysis of Real-World Data

BACKGROUND

Evidence on the accuracy of sentinel lymph node biopsy (SLNB) after neoadjuvant therapy (NAT) for patients with breast cancer is inconclusive. This study reviewed the real-world data to determine the acceptability of SLNB after NAT.

METHODS

The study searched for articles in the PubMed, EMBASE, and Cochrane Library databases. The primary outcomes were the identification rate for sentinel lymph nodes (SLNs) and the false-negative rate (FNR) for SLNB. The study also evaluated the FNR in subgroups defined by tumor stage, nodal stage, hormone receptor status, human epidermal growth factor receptor-2 status, tumor response, mapping technique, and number of SLNs removed.

RESULTS

The study retrieved 61 prospective and 18 retrospective studies with 10,680 initially cN± patients. The pooled estimate of the identification rate was 0.906 (95 % confidence interval [CI], 0.891-0.922), and the pooled FNR was 0.118 (95 % CI, 0.103-0.133). In subgroup analysis, the FNR was significantly higher for the patients with estrogen receptor (ER)-negative status and fewer than three SLNs removed. The FNR did not differ significantly between the patients with and those without complete tumor response. Among the patients with initial clinical negative axillary lymph nodes, the incidence of node metastasis was 26.8 % (275/1041) after NAT.

CONCLUSION

Real-world evidence indicates that the FNR of SLNB after NAT in breast cancer is 11.8 %, exceeding only slightly the commonly adopted threshold of 10 %. The FNR is significantly higher for patients with ER-negative status and removal of fewer than three SLNs. Using a dual tracer and removing at least three SLNs may increase the accuracy of SLNB after NAT.

Sentinel Lymph Node Biopsy in Breast Cancer Patients With Pathological Complete Response in the Axillary Lymph Node After Neoadjuvant Chemotherapy

Purpose

Sentinel lymph node biopsy (SLNB) alone following neoadjuvant chemotherapy (NAC) remains controversial in patients with breast cancer who are initially lymph node-positive. The present study aimed to evaluate the impact of SLNB and axillary lymph node dissection (ALND) on breast cancer recurrence and survival in patients who converted from lymph node-positive to pathological node-negative (ypN0) after NAC.

Methods

This single-center retrospective study included 223 patients who converted to axillary lymph node-negative status after NAC and underwent breast and axillary surgery between January 2006 and December 2015. This study compared the overall survival (OS), disease-free survival (DFS), ipsilateral axillary lymph node recurrence rates and incidence of postoperative complications, especially, arm lymphedema and shoulder stiffness between SLNB and ALND.

Results

This study included 223 patients with axillary pathological complete response (pCR) after NAC and surgery. The SLNB and ALND groups included 94 and 129 patients, respectively. The median follow-up time was 57 (range, 6–155) in the SLNB group and 99 (range 2–159) months in the ALND group. The corresponding 5-year OS and DFS rates were 96.3% and 94.2% (p = 0.392), and 89.2% and 86.4% (p = 0.671), respectively. Four patients (4.3%) in the SLNB group and nine (7.0%) in the ALND group developed locoregional recurrences. Ipsilateral axillary lymph node recurrence and distant metastasis were observed in one (1.1%) and three (2.3%) patients, and in 10 (10.6%) and 11 (8.5%) patients, respectively. Patients in the ALND group were more likely than their SLNB counterparts to experience complications, such as shoulder stiffness (9 [7.0%] vs. 4 [4.3%] patients, p = 0.57). The rate of lymphedema in the ALND group was three times that in the SLNB group (35 [27.1%] vs. 8 [8.5%] patients, p < 0.001).

Conclusion

As an alternative to ALND, SLNB has oncological safety in patients with axillary pathological complete response after NAC.

Sentinel lymph node mapping in breast cancer patients following neoadjuvant chemotherapy: systematic review and meta-analysis about head to head comparison of cN0 and cN + patients

PURPOSE

The effectiveness of sentinel lymph node (SLN) mapping and biopsy following neoadjuvant chemotherapy (NAC) in axillary lymph node staging of breast cancer (BCa) patients with initial clinical node positive status (cN +) compared to clinical node negative status (cN0) is not yet known. The aim of this meta-analysis was to compare the accuracy of SLN mapping following NAC in cN + and cN0 BCa patients.

METHODS

PubMed and Scopus were comprehensively reviewed to retrieve all the studies that performed SLN mapping/biopsy and standard axillary lymph node dissection on cN0 and cN + BCa patients following NAC. Pooled detection and false negative rates for N0 and N + patients including 95% confidence interval values (95% CI) were evaluated. Odds ratio (OR) and risk difference (RD) of SLN detection failure and false negative results were compared between two groups.

RESULTS

A total of 27 articles were included for SLN detection rate evaluation and 17 for false negative assessment. The OR and RD of detection failure in N + group compared with N0 group following NAC were 2.22 (p = 0.00, 95% CI 1.4-3.4) and 4% (p = 0.00, 95% CI 2-6%), respectively. The OR and RD of false negative rate were 1.6 (p = 0.01, 95% CI 1-2.6) and 8% (p = 0.02, 95% CI 1-14%), respectively.

CONCLUSION

SLN mapping in BCa patients following NAC shows high risk of detection failure and high false negative rate of SLN biopsy in cN + patients. In comparison with cN0 BCa patients, SLN mapping and biopsy after NAC was associated with almost two times higher odds of detection failure and false negative results in cN + patients; therefore, this method should not be recommended in this group of patients.

Long-term prognosis in breast cancer is associated with residual disease after neoadjuvant systemic therapy but not with initial nodal status

BACKGROUND

This follow-up analysis of a Swedish prospective multicentre trial had the primary aim to determine invasive disease-free (IDFS), breast cancer-specific (BCSS) and overall survival (OS) rates, and their association with axillary staging results before and after neoadjuvant systemic therapy for breast cancer.

METHODS

Women who underwent neoadjuvant systemic therapy for clinically node-positive (cN+) or -negative (cN0) primary breast cancer between 2010 and 2015 were included. Patients had a sentinel lymph node biopsy before and/or after neoadjuvant systemic therapy, and all underwent completion axillary lymph node dissection. Follow-up was until February 2019. The main outcome measures were IDFS, BCSS and OS. Univariable and multivariable Cox regression analyses were used to identify independent factors associated with survival.

RESULTS

The study included a total of 417 women. Median follow-up was 48 (range 7-114) months. Nodal status after neoadjuvant systemic therapy, but not before, was significantly associated with crude survival: residual nodal disease (ypN+) resulted in a significantly shorter 5-year OS compared with a complete nodal response (ypN0) (83·3 versus 91·0 per cent; P = 0·017). The agreement between breast (ypT) and nodal (ypN) status after neoadjuvant systemic therapy was high, and more so in patients with cN0 tumours (64 of 66, 97 per cent) than those with cN+ disease (49 of 60, 82 per cent) (P = 0·005). In multivariable analysis, ypN0 (hazard ratio 0·41, 95 per cent c.i. 0·22 to 0·74; P = 0·003) and local radiotherapy (hazard ratio 0·23, 0·08 to 0·64; P = 0·005) were associated with improved IDFS, and triple-negative molecular subtype with worse IDFS.

CONCLUSION

The present findings underline the prognostic significance of nodal status after neoadjuvant systemic therapy. This confirms the clinical value of surgical axillary staging after neoadjuvant systemic therapy.

Usefulness and Prospects of Sentinel Lymph Node Biopsy for Patients With Breast Cancer Using the Medical Imaging Projection System

Background

The Medical Imaging Projection System (MIPS) projects indocyanine green (ICG) fluorescence images directly on the surgical field using a projection mapping technique. We conducted an observational study of sentinel lymph node (SLN) biopsy using the prototype MIPS; we found a high identification rate. However, the number of SLN-positive cases was small, and the sensitivity could not be evaluated. The aim of this study was to investigate the clinical usefulness of the MIPS assisted ICG fluorescence method using commercially available equipment.

Methods

This was a retrospective observational study. Patients with primary breast cancer who underwent SLN biopsy using the MIPS at Kyoto University Hospital from April to December 2020 were included in the study. The primary endpoints were the identification rate of SLNs and detection of positive SLNs by the MIPS. The secondary endpoint was the number of SLNs excised using the MIPS per patient. We also conducted a questionnaire survey focused on the utility of the MIPS; it involved doctors with an experience in using the MIPS.

Results

Seventy-nine patients (84 procedures) were included in the study. In 60 (71%) procedures, both the radioisotope (RI) method and MIPS were used. At least one SLN could be detected by the MIPS in all the procedures, with an identification rate of 100% (95% confidence interval 95.6–100%). A total of 19 (7%) positive SLNs were removed, which were identifiable by the MIPS. Among 57 patients in whom the MIPS and RI methods were used, there was no positive SLN only identified by the RI method. The results of the questionnaire survey showed that the MIPS enabled the operator and assistant to share the ICG fluorescence image in the surgical field and to communicate with each other easily.

Conclusion

The current study demonstrated that the identification rate of SLNs using the MIPS was high, and the MIPS can be used for detecting positive SLNs. It was suggested that the MIPS will be useful in learning SLN biopsy procedures.

Minimal Invasive and Individualizing Management of the Axillary Nodes

The status of the axillary lymph nodes is one of the most important prognostic factors for patients with breast cancer. For over 100 years, axillary lymph node dissection was the standard approach to obtain and manage axillar lymph node, but now, sentinel lymph node biopsy has become a standard approach with less morbidity and equal accuracy in clinical node-negative patients. In addition, numerous studies are on the way to omit axillary lymph node dissection in specific patient subgroups. The recent trials like the ACOSOG Z0011 showed the evidence that omitting an ALND in patients with low burden nodal disease is safe in patients receiving whole-breast radiation. To reduce the use of ALND is the goal to consider when selecting an axillary management strategy.

Factors Associated with Nodal Pathologic Complete Response Among Breast Cancer Patients Treated with Neoadjuvant Chemotherapy: Results of CALGB 40601 (HER2+) and 40603 (Triple-Negative) (Alliance)

BACKGROUND

De-escalation of axillary surgery after neoadjuvant chemotherapy (NAC) requires careful patient selection. We seek to determine predictors of nodal pathologic complete response (ypN0) among patients treated on CALGB 40601 or 40603, which tested NAC regimens in HER2+ and triple-negative breast cancer (TNBC), respectively.

PATIENTS AND METHODS

A total of 760 patients with stage II-III HER2+ or TNBC were analyzed. Those who had axillary surgery before NAC (N = 122), or who had missing pretreatment clinical nodal status (cN) (N = 58) or ypN status (N = 41) were excluded. The proportion of patients with ypN0 disease was estimated for those with and without breast pathologic complete response (pCR) according to pretreatment nodal status.

RESULTS

In 539 patients, the overall ypN0 rate was 76.3% (411/539) to 93.2% (245/263) in patients with breast pCR and 60.1% (166/276) with residual breast disease (RD) (P < 0.0001). For patients who were cN0 pretreatment, the ypN0 rate was 88.8% (214/241), 96.3% (104/108) with breast pCR, and 82.7% (110/133) with RD. For patients who were cN1, 66.2% (157/237) converted to ypN0, 91.7% (111/121) with breast pCR and 39.7% (46/116) with RD. For patients who were cN2/3, 65.6% (40/61) converted to ypN0, 88.2% (30/34) with breast pCR and 37.0% (10/27) with RD. On multivariable analysis, only pretreatment clinical nodal status and breast pCR/RD were associated with ypN0 status (both P < 0.0001).

CONCLUSIONS

Breast pCR and pretreatment nodal status are predictive of ypN0 axillary nodal involvement, with < 5% residual nodal disease among cN0 patients who experience breast pCR. These findings support the incorporation of axillary surgery de-escalation strategies into NAC trials.

Predictors of Nodal Pathological Complete Response in Asian Women with Stage II-III Node-Positive Breast Cancer

BACKGROUND

Neoadjuvant chemotherapy (NAC) is increasingly used to treat node-positive (N+) breast cancer. Predictors of nodal pathological complete response (pCR) in Asian women are poorly described and there is variety in the management of the axilla after NAC. We evaluated predictors of nodal pCR and axillary management in a cohort of Asian N+ patients.

METHODS

Consecutive biopsy-proven N+ breast cancer patients treated with NAC were identified from the Shanghai Ruijin Hospital in China. Axillary lymph node dissection was performed on all patients, irrespective of the nodal response to NAC.

RESULTS

A total of 323 patients were included. Nodal pCR was achieved in 105 patients (33%), 15% of HR+/HER2- tumors, 38% of HR+/HER2+ tumors, 49% of HR-/HER2+ tumors, and 42% of HR-/HER2-tumors (p < 0.001). Factors associated with nodal pCR were (1) receptor status (HR+/HER2- [referent]: OR 3.42, 95% CI 1.43-8.16, p = 0.006 for HR+/HER2+; OR 4.19, 95% CI 1.85-9.50, p = 0.001 for HR-/HER2+; and OR 2.94, 95% CI 1.11-7.74, p = 0.029 for HR-/HER2-), (2) breast pCR (no pCR [referent]: OR 15.22, 95% CI 6.29-36.79, p < 0.001), and (3) absence of lymphovascular invasion (LVI [referent]: OR 9.04, 95% CI 2.09-39.18, p = 0.003).

CONCLUSION

This study confirmed expected predictors of nodal pCR in Asian women and the benefit of NAC in downstaging the axilla independently of ethnicity.

Sentinel Node Biopsy after Neoadjuvant Chemotherapy for Breast Cancer: Preliminary Experience with Clinically Node Negative Patients after Systemic Treatment

Sentinel lymph node biopsy (SLNB) following neoadjuvant treatment (NACT) has been questioned by many studies that reported heterogeneous identification (IR) and false negative rates (FNR). As a result, some patients receive axillary lymph node dissection (ALND) regardless of response to NACT, leading to a potential overtreatment. To better assess reliability and clinical significance of SLNB status on ycN0 patients, we retrospectively analyzed oncological outcomes of 399 patients treated between January 2016 and December 2019 that were either cN0-ycN0 (219 patients) or cN1/2-ycN0 (180 patients). The Endpoints of our study were to assess, furthermore than IR: oncological outcomes as Overall Survival (OS); Distant Disease Free Survival (DDFS); and Regional Disease Free Survival (RDFS) according to SLNB status. SLN identification rate was 96.8% (98.2% in patients cN0-ycN0 and 95.2% in patients cN+-ycN0). A median number of three lymph nodes were identified and removed. Among cN0-ycN0 patients, 149 (68%) were confirmed ypN0(sn), whereas regarding cN1/2-ycN0 cases 86 (47.8%) confirmed an effective downstaging to ypN0. Three year OS, DDFS and RDFS were significantly related to SLNB positivity. Our data seemed to confirm SLNB feasibility following NACT in ycN0 patients, furthermore reinforcing its predictive role in a short observation timing.

Association between tumor molecular subtype, clinical stage and axillary pathological response in breast cancer patients undergoing complete pathological remission after neoadjuvant chemotherapy: potential implications for de-escalation of axillary surgery

Background

Axillary node status is used in clinical practice to guide the selection of axillary surgery in breast cancer patients. However, to date, the optimal axillary management following neoadjuvant therapy (NAT) for breast cancer remains controversial. Our study aimed to investigate the association of molecular subtype, clinical stage, and ypN status after NAT in breast cancer patients, especially those achieving breast pathological complete remission (pCR).

Patients and methods

Patients receiving ⩾4 cycles of NAT were retrospectively included between January 2009 and January 2020. ypN status was compared among patients with different breast pCR statuses, clinical stages, and molecular subtypes in univariate and multivariate analyses.

Results

A total of 1999 patients were included: 457 (22.86%), 884 (44.22%), and 658 (32.92%) patients with cT1-2N0, cT1-2N1, and locally advanced breast cancer (LABC), respectively. Altogether, 435 (21.8%) patients achieved breast pCR: 331 with ypN- and 104 with ypN+ status. Patients achieving breast pCR had a significantly lower ypN+ rate than those without pCR [23.9% versus 62.5%, odds ratio (OR) = 0.14, 95% confidence interval (CI) = 0.09-0.21]. For patients with breast pCR, the ypN+ rate was 6.4%, 25.7%, and 33.9% in cT1-2N0, cT1-2N1, and LABC patients, respectively (p < 0.001). Furthermore, the ypN+ rate was 30.8%, 16.8%, 17.5%, 29.6%, and 27.6% in breast pCR patients with the Luminal A, Luminal B (HER2+), HER2-amplified, Luminal B (HER2-), and triple-negative subtype, respectively. Luminal B (HER2+) (OR = 0.20, 95% CI = 0.05-0.82) and HER2-amplified (OR = 0.19, 95% CI = 0.05-0.83) tumors were associated with lower ypN+ rates. Moreover, 100% of breast pCR patients with cT1-2N0 and HER2-positive disease achieved pathological pN0.

Conclusion

In breast pCR patients after NAT, clinical stage and molecular subtype were significantly associated with ypN status. Patients with cT1-2N0 and HER2-positive disease who achieved breast pCR had a very low ypN+ rate, possibly indicating the possibility for de-escalation of axillary surgery in this patient subgroup.

Management of the axilla with sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer: A single-center study

The neoadjuvant chemotherapy (NAC) is the gold standard initial treatment of the locally advanced breast cancer (LABC). However, the reliability of methods that used to assess response the NAC is still controversial. In this study, patients with LABC who underwent NAC were evaluated retrospectively. The assessment of response to NAC and the effect of axillary approach were investigated on LABC course.The study comprised 94 patients who received NAC with an LABC diagnosis between 2008 and 2020. In our center, magnetic resonance imaging, ultrasonography, and F-flouro deoxyglucose positron emission tomography/computed tomography, and, for some patients, fine-needle aspiration biopsy of suspicious axillary lymph nodes have been performed to assess the effects of NAC. Patients with positive hormone receptor status received adjuvant hormonotherapy, and those with human epidermal growth factor receptor 2 gene expression were treated with trastuzumab. Adjuvant radiotherapy was applied to all patients undergoing breast conserving surgery. Radiotherapy was applied to the peripheral lymphatic areas in the clinical N1 to N3 cases regardless of the response to NAC.The clinical response to the NAC was found that partial in 59% and complete in 19% of the patients. However, 21.2% of the patients were unresponsive. The mean of lymph nodes that excised with the procedure of sentinel lymph node biopsy (SLNB) was 2.4 (range 1-7). In 22 of the 56 patients who underwent SLNB, axillary dissection (AD) was added to the procedure upon detection of metastasis in frozen section examinations. There was no difference between the SLNB and AD groups regarding overall survival (OS; P = .472) or disease-free survival (DFS) rates (P = .439). However, there were differences in the OS (P < .05) and DFS (P = .05) rates on the basis of the LABC histopathological subtypes.The study found that a relationship between molecular subtypes and LABC survival. However, the post-NAC axillary approach had no effect on OS or DFS. Therefore, multiple imaging and interventional methods are needed for the evaluation of NAC response. In addition, morbidity can be avoided after AD by the use of SLNB in cN0 patients.

Residual Axillary Burden After Neoadjuvant Chemotherapy (NACT) in Early Breast Cancer in Patients with a priori Clinically Occult Nodal Metastases - a transSENTINA Analysis

Background Among patients with breast cancer undergoing neoadjuvant chemotherapy (NACT), the association between pathological complete remission (pCR) in the breast and clinical/pathological parameters is well established, whereas the association between these parameters and residual axillary involvement after NACT remains unclear.

Methods Patients with clinically occult nodal metastases (i.e. negative by clinical assessment but positive by SLNB prior to NACT, i.e. Arm B of the SENTINA trial) were included in the presented analysis. All patients received a second sentinel lymph node biopsy (SLNB) and axillary dissection after NACT. Univariate and multivariate analyses were carried out to evaluate the association between clinical/pathological parameters and axillary involvement after NACT.

Results Arm B of the SENTINA study contained 360 patients, 318 of which were evaluable for this analysis. After NACT, 71/318 (22.3%) patients had involved SLNs or non-SLNs after NACT. Overall, 71/318 (22.3%) patients achieved a pCR in the breast. Associations of extranodal spread, lack of multifocality and pCR in the breast with residual axillary burden were statistically significant. In a descriptive analysis including all patients with clinically negative axilla before NACT in the SENTINA trial 1.2% of triple negative (TN) patients and 0.5% of HER/2 positive patients had residual axillary disease in case of a breast pCR.

Conclusions Patients in the SENTINA trial with clinically negative axilla and involved SLNs still carried a significant risk of nodal metastases after NACT. However, the risk of residual axillary burden was particularly low in TN and HER/2 positive tumors in case of a breast pCR.

Axillary management after neoadjuvant treatment

Since its introduction nearly 30 years ago, sentinel lymph node biopsy (SLNB) has become the standard technique to stage the axilla for the great majority of patients with early breast cancer. While the accuracy of SLNB in clinically node-negative patients who undergo neoadjuvant chemotherapy (NAC) is similar to the upfront surgery setting, modifications of the technique to improve the false negative rate are necessary in node-positive patients at presentation. Currently, patients who present with matted nodes, cN1 patients who fail to downstage to cN0 with NAC and those with pathological residual disease have an indication to undergo axillary lymph node dissection. Ongoing trials will confirm if extensive nodal irradiation can replace surgery in patients with residual nodal disease after NAC and if nodal radiotherapy can be omitted in patients who achieve nodal pathological complete response. The aim of this review was to focus on the open questions on the management of the axilla after NAC.

Can we avoid axillary lymph node dissection in N2 breast cancer patients with chemo-sensitive tumours such as HER2 and TNBC?

PURPOSE

To find a group of cN2 patients or patients with high axillary burden who become ypN0 after neoadjuvant chemotherapy (NACT) and who may benefit from avoiding a lymphadenectomy.

METHODS

A retrospective observational cohort study was conducted with 221 clinically staged N2 patients or patients with at least 3 suspicious lymph nodes found by ultrasound at diagnosis. The predictive factors for ypN0 analysed were age, MRI-determined tumour size, histological subtype, the Nottingham histologic grade, surrogate molecular subtype, ki-67 and vascular invasion when present. Clinical and radiological responses after NACT were also evaluated. Univariate and multivariate analyses by logistic regression were performed. Distant disease-free survival (DDFS) was calculated in relation to the status of the axillary lymph nodes after NACT.

RESULTS

After NACT, 89 patients (40.3%) had axillary pathologic complete response (pCR) (ypN0) and 132 (59.7%) had residual axillary disease (ypN+). Molecular surrogate subtype, Ki-67 expression, and the clinical and radiological responses to NACT were the only independent factors associated with ypN0. Axillary pCR was observed more often in HER2-positive and triple-negative tumours than in luminal ones (OR 7.5 and 3.6, respectively). DDFS was 88.7% (95% CI 80.7-96.7%) for ypN0 and 56.2% (95% CI 32.1-80.3%) for ypN+ (p = 0.09).

CONCLUSIONS

In HER2-positive and triple-negative breast cancer patients staged as cN2 or with high axillary burden before NACT, a sentinel lymph node biopsy after NACT could be recommended if there is a clinical and radiological response.

Modern surgical treatment of breast cancer

Breast cancer is the most frequent cancer in women all over the world. The prognosis is generally good, with a five-year overall survival rate above 90% for all stages. It is still the second leading cause of cancer-related death among women. Surgical treatment of breast cancer has changed dramatically over the years. Initially, treatment involved major surgery with long hospitalization, but it is now mostly accomplished as an outpatient procedure with a quick recovery. Thanks to well-designed retrospective and randomly controlled prospective studies, guidelines are continually changing. We are presently in an era where safely de-escalating surgery is increasingly emphasized. Breast cancer is a heterogenous disease, where a "one-size-fits-all" treatment approach is not appropriate. There is often more than one surgical solution carrying equal oncological safety for an individual patient. In these situations, it is important to include the patient in the treatment decision-making process through well informed consent. For this to be optimal, the physician must be fully updated on the surgical options. A consequence of an improved prognosis is more breast cancer survivors, and therefore physical appearance and quality of life is more in focus. Modern breast cancer treatment is increasingly personalized from a surgical point of view but is dependent on a multidisciplinary approach. Detailed algorithms for surgery of the breast and the axilla are required for optimal treatment and quality control. This review illustrates how breast cancer treatment has changed over the years and how the current standard is based on high quality scientific research.

Methylene Blue Absorption in Sentinel Lymph Node Biopsy for Early Breast Cancer after Neoadjuvant Chemotherapy

INTRODUCTION

Chemotherapy is claimed to cause lymphatic drainage damage because of the tumor cell's apoptosis process. This event might cause decreased marker (radioactive solution and/or blue dye) absorption on sentinel lymph nodes (SLN). In this study, the researchers used methylene blue only and wished to evaluate the methylene blue absorption of the SLNB procedure on early-stage breast-cancer patients after neoadjuvant chemotherapy (NAC).

MATERIALS AND METHODS

The method used was the historical cohort study conducted from 2016-2019 in Indonesia. Samples were collected from 117 patients of stage I and II breast cancer with clinically negative axillary lymph nodes, who were then grouped into post-NAC and no-NAC (control group), in which SLNB procedures were conducted on the two groups by using single-method methylene blue. The results of methylene blue absorption were then analyzed by the Chi-square hypothesis test.

RESULTS

From the total of 564 early-stage patients who were referred to surgical oncologists, 117 patients were found to meet criteria of inclusion, consisting of the control group (52 patients) and the post-NAC group (65 patents). Of 65 patients who had undergone NAC treatment and SLNB procedure, it was found that 40 patients (61.5%) showed positive blue SLN. Of 52 pre-NAC breast-cancer patients, it was found that 47 patients (90.4%) showed methylene blue absorption on SLN with the p-value of 0.000 (P<0.05, significant). The relative risk value amounted to 0.522. Post-NAC patients had a tendency of decreased absorption of methylene blue.

CONCLUSION

Neoadjuvant chemotherapy can cause the decrease of methylene blue absorption on SLNB procedure.

Management of the Axilla after Neoadjuvant Systemic Therapy

OPINION STATEMENT

As the use of neoadjuvant systemic therapy (NAST) increases, the optimal management of the axilla has become increasingly complex. Consensus among professional organizations is that those patients with clinically negative axillary nodes who are being considered for NAST should undergo a sentinel lymph node (SLN) biopsy following NAST. If a positive SLN is subsequently identified, an axillary lymph node dissection (ALND) is the current standard of care. For patients with clinically node-positive disease, SLN biopsy is a reasonable option for those with a good response to NAST. Patients should undergo SLN mapping with a dual dye technique. Additionally, at least 2 lymph nodes should be removed, including the previously biopsied and marked lymph node with cancer. In this setting, the identification and false negative rates are acceptable. Patients found to have a negative SLN at this time may be spared the morbidity associated with ALND. Patients found to have persistently positive lymph nodes following NAST, either clinically or pathologically, should undergo a complete ALND.

Adequate sentinel node harvest is associated with low false negative rate in breast cancer managed with neoadjuvant chemotherapy and targeted axillary dissection

INTRODUCTION

After neoadjuvant chemotherapy (NAC) for clinically node-positive breast cancer (NPBC), targeted axillary dissection (TAD) reduces the false negative rate (FNR) of axillary node sampling. Axillary lymph node dissection (ALND) is indicated if the clipped node cannot be identified. Prior studies have indicated that a sentinel lymph node harvest (SLNH) of ≥3 also leads to low FNR. We investigated the performance of SLNH thresholds at inferring the status of the axilla during TAD.

METHODS

Retrospective review of the Legacy Health System Tumor Registry was performed. We identified NPBC patients between 2011 and 2016 managed with NAC and TAD.

RESULTS

In 29 patients, the FNR of the SLNB component of TAD was 11% with SLNH of ≥3; with SLNH of ≤2 nodes the FNR was 20%.

CONCLUSIONS

In patients with NPBC receiving NAC, adequate SLNH is associated with acceptably low FNR. The decision to pursue ALND for clip identification should be made on a case-by-case basis.

Axillary Nodal Burden Assessed with Pretreatment Breast MRI Is Associated with Failed Sentinel Lymph Node Identification after Neoadjuvant Chemotherapy for Breast Cancer

Background After publication of the findings of the American College of Surgeons Oncology Group Z1071 trial, sentinel lymph node biopsy (SLNB) has been increasingly performed in patients with breast cancer after neoadjuvant chemotherapy (NAC). Purpose To investigate the pretreatment breast MRI and clinical-pathologic characteristics associated with failed sentinel node identification after NAC in patients with breast cancer. Materials and Methods Patients who underwent SLNB after NAC between January 2015 and January 2019 were retrospectively identified. Two radiologists independently reviewed the characteristics of axillary nodes (number, perinodal infiltration, cortical thickness, and maximal diameter) at pretreatment breast MRI. The associations of the clinical-pathologic and imaging characteristics of the axillary nodes with sentinel node identification were assessed by using the χ² test and/or the χ² test for trend and multivariable logistic regression with odds ratio (OR) calculation. Results A total of 276 women (mean age ± standard deviation, 48 years ± 9; range, 27-68 years) were included. Sentinel nodes were identified in 252 of the 276 patients (91%). Multivariable analysis showed that higher (stage 3 or 4) clinical T stages (OR = 5.2, P = .004 for radiologist 1; OR = 4.6, P = .01 for radiologist 2), use of a single tracer (OR = 4.3, P = .04 for radiologist 1; OR = 3.9, P = .046 for radiologist 2), a greater number (10 or more) of suspicious axillary nodes (OR = 11.5, P = .002 for radiologist 1; OR = 8.3, P = .01 for radiologist 2), and the presence of perinodal infiltration (OR = 7.0, P = .002 for radiologist 1; OR = 7.5, P = .003 for radiologist 2) were associated with failed sentinel node identification. Conclusion A greater number of suspicious axillary nodes and the presence of perinodal infiltration at pretreatment MRI, higher clinical T stages, and use of a single tracer were independently associated with failed sentinel node identification after neoadjuvant chemotherapy in patients with breast cancer. © RSNA, 2020 See also the editorial by Imbriaco in this issue.

A New Model Incorporating Axillary Ultrasound After Neoadjuvant Chemotherapy to Predict Non-Sentinel Lymph Node Metastasis in Invasive Breast Cancer

Purpose

Few models with good discriminative power have been introduced to predict the risk of non-sentinel lymph node (non-SLN) metastasis in breast cancer after neoadjuvant chemotherapy (NAC). We aimed to develop a new and simple model for predicting the probability of non-SLN metastasis in breast cancer and facilitate the selection of patients who could avoid unnecessary axillary lymph node dissection following NAC.

Patients and Methods

A total of 298 patients diagnosed with invasive breast cancer, who underwent SLN biopsy after completing NAC and subsequently breast surgery, were included and classified into the training set (n=228) and testing set (n=70). Univariate and multivariate analyses were used to select factors that could be determined prior to breast surgery and significantly correlated with non-SLN metastasis in the training set. A logistic regression model was developed based on these factors and validated in the testing set.

Results

Nodal status before NAC, post-NAC axillary ultrasound status, SLN number, and SLN metastasis number were independent predictors of non-SLN metastases in breast cancer after NAC. A predictive model based on these factors yielded an area under the curve of 0.838 (95% confidence interval: 0.774-0.902, p< 0.001) in the training set. When applied to the testing set, this model yielded an area under the curve of 0.808 (95% confidence interval: 0.609-1.000, p= 0.003).

Conclusion

A new and simple model, which incorporated factors that could be determined prior to breast surgery, was developed to predict non-SLN metastasis in invasive breast cancer following NAC. Although this model performed excellently in internal validation, it requires external validation before it can be widely utilized in the clinical setting.

Extent of axillary surgery in inflammatory breast cancer: a survival analysis of 3500 patients

PURPOSE

Inflammatory breast cancer (IBC) is an aggressive variant for which axillary lymph node (LN) dissection following neoadjuvant chemotherapy (NACT) remains standard of care. But with increasingly effective systemic therapy, it is unclear whether more limited axillary surgery may be appropriate in some IBC patients. We sought to examine whether extent of axillary LN surgery was associated with overall survival (OS) for IBC.

METHODS

Female breast cancer patients with non-metastatic IBC (cT4d) diagnosed 2010-2014 were identified in the National Cancer Data Base. Cox proportional hazards modeling was used to estimate the association between extent of axillary surgery (≤ 9 vs ≥ 10 LNs removed) and OS after adjusting for covariates, including post-NACT nodal status (ypN0 vs ypN1-3) and radiotherapy receipt (yes/no).

RESULTS

3471 patients were included: 597 (17.2%) had cN0 disease, 1833 (52.8%) had cN1 disease, and 1041 (30%) had cN2-3 disease. 49.9% of cN0 patients were confirmed to be ypN0 on post-NACT surgical pathology. Being ypN0 (vs ypN1-3) was associated with improved adjusted OS for all patients. Radiotherapy was associated with improved adjusted OS for cN1 and cN2-3 patients but not for cN0 patients. Regardless of ypN status, there was a trend towards improved adjusted OS with having ≥ 10 (vs ≤ 9) LNs removed for cN2-3 patients (HR 0.78, 95% CI 0.60-1.01, p = 0.06) but not for cN0 patients (p = 0.83).

CONCLUSIONS

A majority of IBC patients in our study presented with node-positive disease, and for those presenting with cN2-3 disease, more extensive axillary surgery is potentially associated with improved survival. For cN0 patients, however, more extensive axillary surgery was not associated with a survival benefit, suggesting an opportunity for more personalized care.

Subtype-Guided 18 F-FDG PET/CT in Tailoring Axillary Surgery Among Patients with Node-Positive Breast Cancer Treated with Neoadjuvant Chemotherapy: A Feasibility Study

BACKGROUND

The purpose of this study was to investigate the value of ¹⁸ [F]-fluorodeoxyglucose (¹⁸ F-FDG) positron emission tomography/computed tomography (PET/CT) in tailoring axillary surgery by predicting nodal response among patients with node-positive breast cancer after neoadjuvant chemotherapy (NAC).

METHODS

One hundred thirty-three patients with breast cancer with biopsy-confirmed nodal metastasis were prospectively enrolled. ¹⁸ F-FDG PET/CT scan was performed before NAC (a second one after two cycles with baseline maximum standardized uptake value [SUV_max ] ≥2.5), and a subset of patients underwent targeted axillary dissection (TAD). All the patients underwent axillary lymph node dissection (ALND). The accuracy was calculated by a comparison with the final pathologic results.

RESULTS

With the cutoff value of 2.5 for baseline SUV_max and 78.4% for change in SUV_max , sequential ¹⁸ F-FDG PET/CT scans demonstrated a sensitivity of 79.0% and specificity of 71.4% in predicting axillary pathologic complete response with an area under curve (AUC) of 0.75 (95% confidence interval, 0.65-0.84). Explorative subgroup analyses indicated little value for estrogen receptor (ER)-negative, human epidermal growth factor receptor 2 (HER2)-positive patients (AUC, 0.55; sensitivity, 56.5%; specificity, 50.0%). Application of ¹⁸ F-FDG PET/CT could spare 19 patients from supplementary ALNDs and reduce one of three false-negative cases in TAD among the remaining patients without ER-negative/HER2-positive subtype.

CONCLUSION

Application of the subtype-guided ¹⁸ F-FDG PET/CT could accurately predict nodal response and aid in tailoring axillary surgery among patients with node-positive breast cancer after NAC, which includes identifying candidates appropriate for TAD or directly proceeding to ALND. This approach might help to avoid false-negative events in TAD.

IMPLICATIONS FOR PRACTICE

This feasibility study showed that ¹⁸ [F]-fluorodeoxyglucose (¹⁸ F-FDG) positron emission tomography/computed tomography (PET/CT) could accurately predict nodal response after neoadjuvant chemotherapy (NAC) among patients with breast cancer with initial nodal metastasis except in estrogen receptor-negative, human epidermal growth factor receptor 2-positive subtype. Furthermore, the incorporation of ¹⁸ F-FDG PET/CT can tailor subsequent axillary surgery by identifying patients with residual nodal disease, thus sparing those patients supplementary axillary lymph node dissection. Finally, we have proposed a possibly feasible flowchart involving ¹⁸ F-FDG PET/CT that might be applied in post-NAC axillary evaluation.

Imaging-Based Approach to Axillary Lymph Node Staging and Sentinel Lymph Node Biopsy in Patients With Breast Cancer

OBJECTIVE. This review provides historical and current data to support the role of imaging-based axillary lymph node staging and sentinel lymph node biopsy as the standard of care for axillary management in women with a diagnosis of breast cancer, before and after neoadjuvant systemic therapy. CONCLUSION. The implications of surgical trials (American College of Surgeons Oncology Group [ACOSOG] Z011 and ACOSOG Z1071) on imaging protocols for the axilla are reviewed, in conjunction with the American Joint Committee on Cancer nodal staging guidelines.

Preoperative morphological diagnosis of axillary lymph nodes in a breast center consultation service: evaluation of fine-needle aspiration and core biopsy techniques

PURPOSE

Preoperative routine examination of axillary lymph nodes (ALN) in breast cancer patients is carried out physically and by ultrasound imaging; unsuspicious nodes will lead to a sentinel node (SN) procedure, suspicious ones require axillary dissection (AD). Pre-operative biopsy techniques like fine needle aspiration (FNA) or core biopsy (CB) may reduce the number of false "suspicious" cases and prevent overtreatment. We evaluated the effectiveness of both biopsy techniques.

MATERIALS AND METHODS

After physical and ultrasound examination 241 suspicious ALNs were found in 214 patients. Ultrasound-guided FNA and/or CB procedures were chosen randomly, resulting in 138 FNA and 86 CB. In 17 further events both FNA and CB were employed. The samples were examined in our Cytology lab or in the Pathology Department and the findings correlated with post-operative histological lymph node reports. Patients with histologically proven breast cancer underwent sentinel node biopsy, cytologically or histologically positive FNA/CB-findings prompted ALN dissection.

RESULTS

Out of 155 FNA samples 34 were not representative (21.9%), 89 showed no tumor cells (57.4%), 30 showed positive tumor cells (19.4%), leaving two missing. All 103 CB showed representative material, positive in 62 (60.2%) and negative in 41 (39.8%) cases. Correlation with histological reports revealed a statistically non-significant advantage for CB over FNA regarding total accuracy (92.9% vs. 78.3%) and sensitivity (92% vs. 73.7%).

CONCLUSIONS

Preoperative CB and alternative FNA are valuable complementary methods of predicting ALN involvement in breast cancer patients and may spare the patient unnecessary ALN dissection.

Is Clinical Exam of the Axilla Sufficient to Select Node-Positive Patients Who Downstage After NAC for SLNB? A Comparison of the Accuracy of Clinical Exam Versus MRI

BACKGROUND

The National Comprehensive Cancer Network (NCCN) endorses sentinel lymph node biopsy (SLNB) in patients with clinically positive axillary nodes who downstage after neoadjuvant chemotherapy (NAC). In this study, we compared the accuracy of post-NAC MRI to clinical exam alone in predicting pathologic status of sentinel lymph nodes in cN1 patients.

METHODS

We identified patients with T0-3, N1 breast cancer who underwent NAC and subsequent SLNB from March 2014 to July 2017. Patients were grouped based on whether a post-NAC MRI was done. MRI accuracy in predicting SLN status was assessed versus clinical exam alone.

RESULTS

A total of 450 patients met initial study criteria; 269 were analyzed after excluding patients without biopsy-confirmed nodal disease, palpable disease after NAC, and failed SLN mapping. Median age was 49 years. Post-NAC MRI was done in 68% (182/269). Patients undergoing lumpectomy vs mastectomy more frequently received a post-NAC MRI (88 vs 54%, p < 0.001). All other clinicopathologic parameters were comparable between those who did and did not have a post-NAC MRI. Thirty percent (55/182) had abnormal lymph nodes on MRI. Among these, 58% (32/55) had a positive SLN on final pathology versus 42% (53/127) of patients with no abnormal lymph nodes on MRI and 52% (45/87) of patients who had clinical exam alone (p = 0.09). MRI sensitivity was 38%, specificity was 76%, and overall SLN status prediction accuracy was 58%.

CONCLUSIONS

Post-NAC MRI is no more accurate than clinical exam alone in predicting SLN pathology in patients presenting with cN1 disease. Abnormal lymph nodes on MRI should not preclude SLNB.

Node positive breast cancer: Concordance between baseline PET/CT and sentinel node assessment after neoadjuvant therapy

INTRODUCTION

Sentinel node biopsy for axillary staging in node positive patients after neoadjuvant treatment is controversial, mainly due to high false negative rates. We examined the concordance between the location of the hot nodes identified on PET-CT at presentation with the location of the sentinel nodes.

MATERAILS AND METHODS

Fifty-eight breast cancer patients undergoing neoadjuvant treatment between January 2013 and September 2018 who had positive regional lymph nodes on PET/CT, and a SPECT/CT lymphoscintigraphy completed before sentinel node biopsy were included. Patient, tumor and treatment characteristics were collected. Images of PET/CT were compared to images of SPECT/CT lymphoscintigraphy post treatment and concordance between location of the hot nodes on PET/CT with the sentinel nodes visualized on SPECT/CT was assessed. Association between patient, tumor and treatment characteristics and concordance between the sentinel node and the hot nodes was determined.

RESULTS

Sentinel nodes were identified in 53 (91%) of the cases in surgery. In 25 (43%) patients, axillary nodes were positive after treatment. In 16 (28%; 95% CI 18, 40) the sentinel node was not one of the hot nodes seen on PET/CT at presentation. Twenty-three (40%) patients had excision of additional axillary nodes. In two patients with non-concordant sentinel nodes, the sentinel node was falsely negative.

CONCLUSIONS

In node positive patients who undergo neoadjuvant treatment, the sentinel node visualized on lymphatic mapping is not necessarily one of the hot nodes identified on PET/CT at presentation. These findings underline the importance of marking the pathologically proven lymph node and excising it as well as the sentinel nodes after treatment.

Sentinel Node Lymph Node Surgery After Neoadjuvant Therapy: Principles and Techniques

Surgical management of the axilla in breast cancer has been a topic of great interest. While sentinel lymph node biopsy (SLNB) is an established approach for patients undergoing surgical treatment as the first element of their care, there is continued debate regarding surgical management of the axilla in patients receiving neoadjuvant chemotherapy (NAC). In clinically node-negative patients, it has been debated whether or not SLNB should be performed before chemotherapy to accurately determine the clinical stage, or after chemotherapy, thus prioritizing the response to therapy and potentially minimizing axillary surgery. Node-positive patients have undergone axillary lymph node dissection in the past, however this paradigm has been challenged in recent years. Thus, surgeons must understand the importance of accurate axillary information both before and after NAC, and its role in multidisciplinary planning. We present a summary of the data surrounding axillary management in patients receiving NAC, and recommendations for surgical technique.

Surgical Management of the Axilla in Clinically Node-Positive Patients Receiving Neoadjuvant Chemotherapy: A National Cancer Database Analysis

BACKGROUND

The feasibility of sentinel lymph node biopsy (SLNB) in patients with clinically node-positive (cN+) disease who convert to clinically node-negative (cN0) disease following neoadjuvant chemotherapy (NAC) has been evaluated in several large clinical trials, but it remains unclear whether the approach has been broadly adopted in the United States.

METHODS

The National Cancer Database was used to identify women diagnosed with cN+ breast cancer who received NAC followed by surgery between 2012 and 2015. Trends in axillary surgery were evaluated and multivariable logistic regression analyses performed to determine factors associated with receipt of SLNB.

RESULTS

Of 12,965 women cN+ at baseline, the use of SLNB increased from 31.8% in 2012 to 49% in 2015 (p < 0.001). Using axillary pCR as a surrogate for patients who convert to cN0 following NAC, among 5127 (39.5%) ypN0 patients, SLNB increased from 38.2 to 58.4% over the study period (p < 0.001), resulting in avoidance of axillary dissection in 42.2% of ypN0 patients by 2015. In adjusted analyses, factors significantly associated with SLNB attempt included cN1 disease, age < 45 years, treatment facility type, triple-negative and HER2-positive subtypes, and year of diagnosis. In women with residual isolated tumor cells (ITCs), micrometastases, and ypN1 disease, SLNB was the only axillary procedure performed in 36.9%, 23.6%, and 13.0% of cases.

CONCLUSIONS

The use of SLNB in cN+ patients receiving NAC increased significantly between 2012 and 2015. SLNB alone was performed in more than 10% of patients with ypN1 disease, 20% with micrometastases, and 35% with ITCs; the oncologic safety of omitting axillary dissection in these patients requires further evaluation.

The Sentinel Lymph Node Biopsy Using Indocyanine Green Fluorescence Plus Radioisotope Method Compared With the Radioisotope-Only Method for Breast Cancer Patients After Neoadjuvant Chemotherapy: A Prospective, Randomized, Open-Label, Single-Center Phase 2 Trial

BACKGROUND

This study aimed to compare the sentinel lymph node (SLN) identification rates for breast cancer patients after neoadjuvant chemotherapy (NAC) between the dual method (DM) of indocyanine green fluorescence (ICG-F) plus a radioisotope (RI) and RI alone.

METHODS

This randomized study enrolled 130 patients who received NAC for breast cancer and 122 patients who received SLN biopsy (SLNB) using either DM (n = 58) or RI only (n = 64). The study compared the identification rate, number of SLNs, and detection time of SLNB.

RESULTS

Among the 122 patients, 113 (92.6%) were clinically node-positive before NAC. The SLN identification rate was 98.3% in the DM group and 93.8% in the RI group (p = 0.14). The DM group and the RI group were similar in the average number of SLNs (2.2 ± 1.13 vs. 1.9 ± 1.33; p = 0.26) and the time to detection of the first SLN (8.7 ± 4.98 vs. 8.3 ± 4.31 min; p = 0.30). In the DM group, transcutaneous lymphatic drainage was visualized by fluorescence imaging for 65.5% (38 of 58) of the patients. The SLN identification rate was 94.7% using ICG-F and 93% using RI (p = 0.79). During and after the operation, no complications, including allergic reactions or skin necrosis, occurred.

CONCLUSIONS

This study is the first randomized trial to use ICG-F for SLNB in breast cancer patients after NAC. The DM including ICG-F could be a feasible and safe method for SLNB in initially node-positive breast cancer patients with NAC.