Clinical utility of routine pre-operative axillary ultrasound and fine needle aspiration cytology in patient selection for sentinel lymph node biopsy

Automated and rapid detection of cancer in suspicious axillary lymph nodes in patients with breast cancer

Preoperative staging of suspicious axillary lymph nodes (ALNs) allows patients to be triaged to ALN dissection or to sentinel lymph node biopsy (SLNB). Ultrasound-guided fine needle aspiration (FNA) and cytology of ALN is moderately sensitive but its clinical utility relies heavily on the cytologist's experience. We proposed that the 5-h automated GeneXpert system-based prototype breast cancer detection assay (BCDA) that quantitatively measures DNA methylation in ten tumor-specific gene markers could provide a facile, accurate test for detecting cancer in FNA of enlarged lymph nodes. We validated the assay in ALN-FNA samples from a prospective study of patients (N = 230) undergoing SLNB. In a blinded analysis of 218 evaluable LN-FNAs from 108 malignant and 110 benign LNs by histology, BCDA displayed a sensitivity of 90.7% and specificity of 99.1%, achieving an area under the ROC curve, AUC of 0.958 (95% CI: 0.928-0.989; P < 0.0001). Next, we conducted a study of archival FNAs of ipsilateral palpable LNs (malignant, N = 72, benign, N = 53 by cytology) collected in the outpatient setting prior to neoadjuvant chemotherapy (NAC). Using the ROC-threshold determined in the prospective study, compared to cytology, BCDA achieved a sensitivity of 94.4% and a specificity of 92.5% with a ROC-AUC = 0.977 (95% CI: 0.953-1.000; P < 0.0001). Our study shows that the automated assay detects cancer in suspicious lymph nodes with a high level of accuracy within 5 h. This cancer detection assay, scalable for analysis to scores of LN FNAs, could assist in determining eligibility of patients to different treatment regimens.

Diagnostic Accuracy of Fine-Needle Aspiration Cytology and Core-Needle Biopsy in the Assessment of the Axillary Lymph Nodes in Breast Cancer-A Meta-Analysis

Background: The present study aims to evaluate the diagnostic accuracy between ultrasonography-guided fine-needle aspiration cytology (US-FNAC) and core needle biopsy (CNB) of axillary lymph nodes (ALNs) in patients with breast cancer through a meta-analysis and a diagnostic test accuracy (DTA) review. Methods: The present meta-analysis and DTA review included 67 eligible studies. The diagnostic accuracy of various preoperative assessments, including US-FNAC and CNB, was evaluated for ALNs assessments in patients with breast cancer. In addition, a subgroup analysis based on methods of cytologic preparation was performed. In the DTA review, the sensitivity, specificity, diagnostic odds ratio (OR) and area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve were calculated. Results: The diagnostic accuracy of the preoperative assessments of ALNs was 0.850 (95% confidence interval (CI) 0.833–0.866) for patients with breast cancer. The diagnostic accuracy of CNB was significantly higher than that of US-FNAC (0.896, 95% CI 0.844–0.932 vs. 0.844, 95% CI 0.825–0.862; p = 0.044 in a meta-regression test). In the subgroup analysis based on cytologic preparation, the diagnosis accuracies were 0.860, 0.861 and 0.859 for the methods of conventional smear, liquid-based preparation and cell block, respectively. In the DTA review, CNB showed higher sensitivity than US-FNAC (0.849 vs. 0.760). However, there was no difference in specificity between US-FNAC and CNB (0.997 vs. 1.000). US-FNAC with liquid-based preparation and CNB showed the highest diagnostic OR and AUC on the SROC, respectively. Conclusion: Both US-FNAC and CNB are useful in preoperative assessments of ALNs in patients with breast cancer. Although the most sensitive test was found to be CNB in this study, there was no difference in specificity between various preoperative evaluations and the application of US-FNAC or CNB may be impacted by various factors.

Shortcomings of ultrasound-guided fine needle aspiration in the axillary management of women with breast cancer

Background

Ultrasound, along with ultrasound-guided fine needle aspiration, is currently used for the axillary evaluation of breast cancer patients in order to identify candidates for axillary lymph node dissection. The aim of this study is to evaluate the accuracy of this tool in correctly identifying patients who may or may not benefit from axillary clearance in light of the ACOSOG Z0011 trial recommendations.

Methods

One hundred one patients (65 with positive US-FNA with corresponding axillary lymph node dissection (ALND), and 36 with negative US-FNA with corresponding ALND/sentinel lymph node biopsy) were studied for the number of involved axillary lymph nodes, tumor clinicopathologic features, and axillary radiologic findings.

Results

From the positive US-FNA group, 43% of patients had two or fewer positive lymph nodes upon ALND pathologic examination. In the US-FNA negative group, the negative predictive value for detecting axillary disease was 72.7%. With both groups combined, the sensitivity, specificity, PPV, and NPV of US-FNA for selecting patients based on axillary disease burden were 86%, 51.7%, 57%, and 83.3%, respectively.

Conclusion

Based on Z0011 guidelines, US-FNA is not a reliable tool in triaging patients in need for ALND and leads to overtreatment of 43% patients when positive, while depriving a small but significant percentage of patients from necessary therapy, when negative.

Fine-Needle Aspiration Biopsy Management of the Axilla in Primary Breast Carcinoma

CONTEXT

Fine-needle aspiration biopsy (FNAB) is frequently used to stage the axilla preoperatively in patients with primary breast carcinoma. In the light of the ACOSOG-Z0011 and AMAROS trials that specified sentinel lymph node biopsy as an inclusion criterion, the role of FNAB in axillary staging is changing.

OBJECTIVE

This article will review the diagnostic accuracy of FNAB in staging of the axilla in patients with primary breast carcinoma. The efficacy of axillary FNAB compared with core-needle biopsy will be evaluated. The evolving approach to staging of the axilla, in the light of ACOSOG-Z0011 and AMAROS trials, will be discussed.

DATA SOURCES

Data were sourced from published peer-reviewed articles in PubMed (US National Library of Medicine) and published guidelines including the European Guidelines for Quality Assurance in Breast Cancer and those from the European Society of Medical Oncology (ESMO), Union for International Cancer (UICC), American Society of Clinical Oncology (ASCO), and the American Society of Breast Surgeons.

CONCLUSIONS

FNAB of the axilla is almost 100% specific with a sensitivity between 40 and 90%. A positive FNAB reduces the need for a second axillary procedure by up to 20% with reduced morbidity and cost. The recent ACOSOG-Z0011 and AMAROS trials have reduced the use of FNAB axilla in American protocols, but it remains the standard of care in Europe.

Utility of Preoperative Staging of Ipsilateral Axilla with Ultrasound and Guided Needle Aspiration in Early-Stage Breast Cancer-Current Indian Scenario

Clinical assessment of the axilla, especially in early-stage breast cancer, can have a high degree of inaccuracy with over-staging curtailing the use of sentinel node biopsy. Imaging of axilla, using ultrasound ± guided fine needle aspiration cytology (FNAC) can help in better staging. In this study, we aim to compare physical examination and ultrasound of axilla and FNAC and assess their accuracy in preoperative staging of axilla. This was a prospective observational study. Patients with biopsy-proven invasive early-stage breast carcinoma, consenting to be part of the study, underwent ultrasound (US) of ipsilateral axilla with guided FNAC, when indicated and underwent surgery which included complete axillary dissection. Postoperative histopathology was compared to preoperative US and guided cytology (if done), to correlate the latter's efficacy in detecting positive axillary nodes. Clinically, 96% of patients had palpable axillary nodes, though of doubtful significance. On US axilla, 62% had suspicious nodes (guided FNAC was performed). Sensitivity and specificity of US axilla was 90.9% and 60.7%, with sensitivity reaching 100% in patients with > 1 node positive, while that of US + FNAC was 85.7 and 100% respectively. Although all US nodal parameters studied showed positive correlation with final nodal pathology (p < 0.005), loss of fatty hilum was the best predictor of metastatic nodal disease. Preoperative ultrasound of ipsilateral axilla ± FNAC helps in better preoperative staging of axilla. Its routine use can help reduce the false positivity of clinical examination and help in avoiding unnecessary axillary dissection and also in better selection of patients for sentinel node biopsy.

Nomogram for prediction of level 2 axillary lymph node metastasis in proven level 1 node-positive breast cancer patients

BACKGROUND

The current management of the axilla in level 1 node-positive breast cancer patients is axillary lymph node dissection regardless of the status of the level 2 axillary lymph nodes. The goal of this study was to develop a nomogram predicting the probability of level 2 axillary lymph node metastasis (L-2-ALNM) in patients with level 1 axillary node-positive breast cancer.

MATERIALS AND METHODS

We reviewed the records of 974 patients with pathology-confirmed level 1 node-positive breast cancer between 2010 and 2014 at the Liaoning Cancer Hospital and Institute. The patients were randomized 1:1 and divided into a modeling group and a validation group. Clinical and pathological features of the patients were assessed with uni- and multivariate logistic regression. A nomogram based on independent predictors for the L-2-ALNM identified by multivariate logistic regression was constructed.

RESULTS

Independent predictors of L-2-ALNM by the multivariate logistic regression analysis included tumor size, Ki-67 status, histological grade, and number of positive level 1 axillary lymph nodes. The areas under the receiver operating characteristic curve of the modeling set and the validation set were 0.828 and 0.816, respectively. The false-negative rates of the L-2-ALNM nomogram were 1.82% and 7.41% for the predicted probability cut-off points of < 6% and < 10%, respectively, when applied to the validation group.

CONCLUSIONS

Our nomogram could help predict L-2-ALNM in patients with level 1 axillary lymph node metastasis. Patients with a low probability of L-2-ALNM could be spared level 2 axillary lymph node dissection, thereby reducing postoperative morbidity.

Role of Axillary Ultrasound, Fine Needle Aspiration Cytology and Sentinel Lymph Node Biopsy in clinically N0 Breast Cancer

This study evaluates the combined role of axillary ultrasound, fine needle aspiration cytology and sentinel lymph node biopsy in clinically N0 axilla. Between January 2014 and June 2015, 150 women with early breast cancer underwent axillary ultrasound as a first investigation for nodal status. Suspicious nodes were subjected to image guided fine needle aspiration cytology. Non-suspicious and fine needle aspiration cytology negative axillary nodes proceeded to sentinel lymph node biopsy at time of primary breast surgery. All confirmed positive (cytology and frozen) cases proceeded to axillary lymph node dissection. 52 women had positive axillary nodes at final histology. Axillary ultrasound with fine needle aspiration cytology identified 27 patients with positive axillary nodal status and had a sensitivity of 84.36 % (27/32) and specificity of 87.5 % (14/16). Intraoperative frozen analysis identified a further 13 cases with sensitivity of 56.52 % (13/23) and specificity of 97.56 % (80/82). Overall 76.92 % (40/52) patients with positive axillary metastasis were identified peri-operatively using combination of axillary ultrasound, cytology and sentinel lymph node biopsy.

Preoperative ultrasound staging of the axilla make's peroperative examination of the sentinel node redundant in breast cancer: saving tissue, time and money

OBJECTIVE

To evaluate the role of preoperative axillary staging with ultrasound (US) and fine needle aspiration cytology (FNAC). Can we avoid intraoperative sentinel lymph node (SLN) examination, with an acceptable revision rate by preoperative staging?

DESIGN

This study is based on the retrospective data of 336 patients that underwent US evaluation of the axilla as part of their staging. A FNAC biopsy was performed when abnormal lymph nodes were visualized. Patients with normal appearing nodes on US or a benign diagnostic biopsy had removal of the SLNs without intraoperative pathological examination. We calculated the sensitivity, specificity and accuracy of US/FNAC in predicting the necessity of an axillary lymphadenectomy. Subsequently we looked at the total cost and the operating time of 3 models. Model A is our study protocol. Model B is a theoretical protocol based on the findings of the Z0011 trial with only clinical preoperative staging and in Model C preoperative staging and intraoperative pathological examination were both theoretically done. sentinel node, staging, ultrasound, preoperative axillary staging, FNAC, axilla RESULTS: The sensitivity, specificity and accuracy are respectively 0.75 (0.66-0.82), 1.00 (0.99-1.00) and 0.92 (0.88-0.94). Only 26 out of 317 (8.2%) patients that successfully underwent staging needed a revision. The total cost of Model A was 1.58% cheaper than Model C and resulted in a decrease in operation time by 9,46%. The benefits compared with Model B were much smaller.

CONCLUSION

Preoperative US/FNAC staging of the axillary lymph nodes can avoid intraoperative examination of the sentinel node with an acceptable revision rate. It saves tissue, reduces operating time and decreases healthcare costs in general.

Predictors for extensive nodal involvement in breast cancer patients with axillary lymph node metastases

PURPOSE

Various prediction models have been developed to predict the risk of having no additional axillary metastases in patients with a positive sentinel lymph node biopsy (SLNB), thereby disregarding patients with a positive ultrasound-guided lymph node biopsy (UGLNB). However, in the post-Z0011 trial era it is important to identify all patients with extensive nodal involvement for whom axillary treatment might still be beneficial. Therefore, the aim of this study is to identify factors predicting extensive nodal involvement (≥3 positive nodes) in the axilla, with the emphasis on the method of axillary staging: node positivity by UGLNB versus SLNB.

METHODS

All patients diagnosed with invasive breast cancer between January 2006 and December 2011 at the Máxima Medical Center were included. Univariate and multivariate logistic regression analyses were performed.

RESULTS

We included 302 cases, representing 301 node positive patients, of whom 177 cases had 1 or 2 positive lymph nodes and 125 cases had ≥3 positive lymph nodes. Multivariate analyses showed that a positive UGLNB (OR = 5.10; 95%CI = 2.78-9.36), lymphovascular invasion (OR = 3.60; 95%CI = 1.79-7.23) and a larger tumor size (OR = 1.03 per mm increase; 95%CI = 1.00-1.06) were significantly associated with extensive nodal involvement in patients with invasive breast cancer.

CONCLUSION

This study shows that a positive axilla, determined by UGLNB, is the most important factor for predicting further extensive nodal involvement. Hence, the role of axillary staging by ultrasound should be redefined since it might play an important role in selecting patients who may still benefit from axillary treatment.

To do or not to do: axillary nodal evaluation after ACOSOG Z0011 Trial

Methods of axillary evaluation in invasive breast cancer continue to evolve. The recent American College of Surgeons Oncology Group Z0011 Trial is a prospective, randomized, multicenter trial that compared the survival and locoregional recurrence rates after complete axillary lymph node dissection (ALND) versus sentinel node biopsy (SNB) alone in women with a positive sentinel node in an effort to avoid the complications associated with ALND. As the results of this trial are implemented clinically, affecting surgical management of axillary metastatic disease, radiologists may need to redefine their role in the preoperative assessment of the axilla. Before the Z0011 trial, breast imagers worked to identify axillary metastases preoperatively, allowing appropriate patients to proceed directly to ALND and avoiding the need for SNB. However, the Z0011 trial concluded that ALND may not be necessary in women with metastatic axillary disease who meet the trial criteria. In the Z0011 trial, after 6 years of median follow-up there was no difference in either locoregional recurrence or survival among the women who underwent SNB alone compared with those who underwent ALND, suggesting that ALND is unnecessary in a subset of women with a positive node at SNB. These results raise questions about how aggressively radiologists should pursue percutaneous sampling of axillary nodes, as some practitioners conclude that, in an otherwise eligible woman, positive results from imaging-guided percutaneous biopsy preclude a Z0011 trial-directed pathway. Debate about the best way to implement the results of the Z0011 trial into daily clinical practice exists. It is important for breast imagers to work closely with breast surgeons to provide the most appropriate treatment course for each patient.

Does a Positive Axillary Lymph Node Needle Biopsy Result Predict the Need for an Axillary Lymph Node Dissection in Clinically Node-Negative Breast Cancer Patients in the ACOSOG Z0011 Era?

BACKGROUND

American College of Surgeons Oncology Group (ACOSOG) Z0011 defined clinical node negativity by physical examination alone. Although axillary ultrasound with biopsy has a positive predictive value for lymph node (LN) metastases approaching 100 %, it may not appropriately identify clinically node-negative women with ≥3 positive LNs who require axillary lymph node dissection (ALND). We sought to identify the total number of positive LNs in women presenting with cT1-2N0 breast carcinoma with a positive preoperative LN biopsy to evaluate the potential for overtreatment when ALND is performed on the basis of a positive needle biopsy in patients who otherwise meet ACOSOG Z0011 eligibility criteria.

METHODS

Patients with cT1-2N0 breast cancer by physical examination with a positive preoperative LN biopsy were identified from a prospective institutional database. Clinicopathologic characteristics and axillary imaging results were compared between women with 1 to 2 total positive LNs and ≥3 total positive LNs.

RESULTS

Between May 2006 and December 2013, a total of 141 women with cT1-2N0 breast cancer had abnormal axillary imaging and a preoperative positive LN biopsy (median patient age 51 years, median tumor size 2.4 cm, 86 % ductal histology, 79 % estrogen receptor positive). Sixty-six women (47 %) had 1 to 2 total positive LNs, and 75 (53 %) had ≥3 total positive LNs. Women with ≥3 total positive LNs had larger tumors (2.4 vs. 2.2 cm, p = 0.03), fewer tumors with ductal histology (79 vs. 94 %, p = 0.01), more lymphovascular invasion (80 vs. 61 %, p = 0.01), and higher median body mass index (29.2 vs. 27.1 kg/m(2), p = 0.04). Having >1 abnormal LN on axillary imaging was significantly associated with having ≥3 total positive LNs at final pathology (68 vs. 43 %, p = 0.003).

CONCLUSIONS

Axillary imaging with preoperative LN biopsy does not accurately discriminate low- versus high-volume nodal disease in clinically node-negative patients.

Staging the axilla in women with breast cancer: the utility of preoperative ultrasound-guided needle biopsy

Preoperative staging of the axilla in women with invasive breast cancer using ultrasound-guided needle biopsy (UNB) identifies approximately 50% of patients with axillary nodal metastases prior to surgical intervention. Although moderately sensitive, it is a highly specific staging strategy that is rarely falsely-positive, hence a positive UNB allows patients to be triaged to axillary lymph-node dissection (ALND) avoiding potentially unnecessary sentinel node biopsy (SNB). In this review, we extend our previous work through an updated literature search, focusing on studies that report data on UNB utility. Based on data for 10,934 breast cancer patients, sourced from 35 studies, a positive UNB allowed triage of 1,745 cases (simple proportion 16%) to axillary surgical treatment: the utility of UNB was a median 19.8% [interquartile range (IQR) 11.6%-26.7%] across these studies. We also modelled data from a subgroup of studies, and estimated that amongst patients with metastases to axillary nodes, the odds ratio (OR) for high nodal disease burden for a positive UNB versus a negative UNB was 4.38 [95% confidence interval (95% CI): 3.13, 6.13], P<0.001. From this model, the estimated proportion with high nodal disease burden was 58.9% (95% CI: 50.2%, 67.0%) for a positive UNB, whereas the estimated proportion with high nodal disease burden was 24.6% (95% CI: 17.7%, 33.2%) if UNB was negative. Overall, axillary UNB has good clinical utility and a positive UNB can effectively triage to ALND. However, the evolving landscape of axillary surgical treatment means that UNB will have relatively less utility where surgeons have modified their practice to omission of ALND for minimal nodal metastatic disease.

Axillary ultrasonography in breast cancer patients helps in identifying patients preoperatively with limited disease of the axilla

BACKGROUND

The sentinel lymph node biopsy (SLNB) procedure is the method of choice for the identification and monitoring of regional lymph node metastases in patients with breast cancer. In the case of a positive sentinel lymph node (SLN), additional lymph node dissection is still warranted for regional control, although 40-65 % have no additional axillary disease. Recent studies show that after breast-conserving surgery, SLNB, and adjuvant systemic therapy, there is no significant difference between recurrence-free period and overall survival if there are ≤2 positive axillary nodes. The purpose of this study was preoperative identification of patients with limited axillary disease (≤2 macrometastases) by using ultrasonography.

METHODS

Data from 1,103 consecutive primary breast cancer patients with tumors smaller than 50 mm, no palpable adenopathy, and a maximum of 2 SLNs with macrometastases were collected. The variable of interest was US of the axilla.

RESULTS

Of the 1,103 patients included, 1,060 remained after exclusion criteria. Of these, 102 (9.6 %) had more than 2 positive axillary nodes on ALND. Selected by unsuspected US, the chance of having >2 positive lymph nodes (LNs) is substantially lower (4.2 %). This is significant on univariate and multivariate analysis. After excluding the patients with extracapsular extension of the SLN, the chance of having >2 positive LNs is only 2.6 %. For pT1-2, this is 2.2 %.

CONCLUSIONS

The risk of more than 2 positive axillary nodes is relatively small in patients with cT1-2 breast cancer. US of the axilla helps in further identifying patients with a minimal risk of additional axillary disease, putting ALND up for discussion.

Performance characteristics of ultrasound-guided fine-needle aspiration of axillary lymph nodes for metastatic breast cancer employing rapid on-site evaluation of adequacy: analysis of 136 cases and review of the literature

BACKGROUND

It has been demonstrated that axillary ultrasound-guided fine-needle aspiration (US-FNA) has excellent positive predictive value for the axillary lymph node status of patients with breast cancer before surgery or neoadjuvant therapy and, thus, can obviate the need for sentinel lymph node biopsy in FNA-positive patients. However, US-FNA has only moderate sensitivity, in part because of the collection of nondiagnostic or equivocal specimens. Rapid on-site evaluation for adequacy (ROSE) can improve definitive diagnosis rates but has not been well characterized in this setting.

METHODS

One hundred thirty-three patients with breast carcinoma were identified who underwent 136 US-FNAs of axillary lymph nodes, all with ROSE, and the results were correlated with the diagnosis on a subsequent surgical procedure.

RESULTS

The adequacy rate was 95.6% (130 of 136 FNAs), and a definitive diagnosis was made in 91.2% (124 of 136 FNAs). Among definite diagnoses, sensitivity was 75%, specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 79%. Sources of false-negative and potential false-positive diagnoses were evaluated among these cases and in the literature.

CONCLUSIONS

Small metastasis size is the most common cause of false-negative results, whereas interpretation errors by pathologists are quite rare. ROSE appears to improve adequacy and definitive diagnosis rates and, thus, can more accurately triage patients to appropriate care.

Sparing sentinel node biopsy through axillary lymph node fine needle aspiration in primary breast cancers

Background

Axillary lymph node status is an important staging and prognostic factor in breast cancer. This study aimed to evaluate the efficacy of axilla fine needle aspiration cytology (FNAC) in primary breast cancer without a palpable node and even without image characteristics of a metastatic node.

Methods

From June 2008 to January 2012, 77 patients met the inclusion criteria of having received a FNAC procedure during the diagnostic protocol of primary breast cancer with the characteristic of impalpable axilla nodes, and of having received axillary surgery after that, according to the guidelines. The patients’ characteristics, clinical-pathological features, pre-operative axillary lymph node FNAC findings, surgical lymph node report, and definite pathologic staging were reviewed.

Results

The FNAC procedures had a reported sensitivity of 58.82%, specificity of 100%, positive predictive value of 100%, negative predictive value of 72.55%, and accuracy of 80.28%. There were no false positives on FNAC; therefore, the positive likelihood ratio approached infinity. The negative likelihood ratio was 41.18%. Axillary lymph node FNAC is feasible in newly diagnosed breast cancer patients to evaluate metastatic lymph nodes even in those without clinical or ultrasonic evidence of lymphadenopathy.

Conclusions

FNAC can be a routine evaluation for most primary breast cancer patients with benefits in expediting treatment. For those patients with positive findings of the axilla, sentinel node biopsy can be avoided.

Feasibility of sentinel lymph node biopsy in breast cancer patients clinically suspected of axillary lymph node metastasis on preoperative imaging

Background

Generally, sentinel lymph node biopsy (SLNB) is performed in patients with clinically negative axillary lymph node (LN). This study was to assess imaging techniques in axillary LN staging and to evaluate the feasibility of SLNB in patients clinically suspected of axillary LN metastasis on preoperative imaging techniques (SI).

Methods

A prospectively maintained database of 767 breast cancer patients enrolled between January 2006 and December 2009 was reviewed. All patients were offered preoperative breast ultrasound, magnetic resonance imaging, and positron emission tomography scanning. SI patients were regarded as those for whom preoperative imaging was “suspicious for axillary LN metastasis” and NSI as “non-suspicious for axillary LN metastasis” on preoperative imaging techniques. Patients were subgrouped by presence of SI and types of axillary operation, and analyzed.

Results

For 323 patients who received SLNB, there was no statistically significant difference in axillary recurrence (P=0.119) between SI and NSI groups. There also was no significant difference in axillary recurrence between SLNB and axillary lymph node dissection (ALND) groups in 356 SI patients (P=0.420). The presence of axillary LN metastasis on preoperative imaging carried 82.1% sensitivity and 45.9% specificity for determining axillary LN metastasis on the final pathology.

Conclusions

SLNB in SI patents is safe and feasible. Complications might be avoided by not performing ALND. Therefore, we recommend SLNB, instead of a direct ALND, even in SI patients, for interpreting the exact nodal status and avoiding unnecessary morbidity by performing ALND.