Axillary Ultrasound Research Articles

Accuracy of sentinel node mapping in patients with biopsy-proven metastatic axillary lymph nodes and upfront surgery: preliminary results of the Multimodal Targeted Axillary Surgery (MUTAS) trial.

Some studies suggested that the patients included in the Z0011 trial may represent patients with ultrasound-negative axillary nodes and axillary invasion diagnosed by sentinel node (SN) biopsy. Nevertheless, the National Comprehensive Cancer Network (NCCN) guidelines recommend SN mapping if 1 or 2 suspicious lymph nodes are identified on axillary ultrasound (AU). The aim of this preliminary phase of the Multimodal Targeted Axillary Surgery (MUTAS) trial was to establish the accuracy of SN mapping in patients with axillary involvement undergoing upfront surgery. Between September 2019 and March 2022, we recruited patients with biopsy-proven metastatic axillary nodes and upfront surgery from a single center. We performed SN mapping in these patients before the surgical intervention, which included axillary lymph node dissection. The biopsy-proven metastatic node, SNs and the remaining axillary nodes were excised separately. SN status was considered representative of the status of the remaining axillary nodes. We calculated the sensitivity, specificity, negative predictive value and positive predictive value of the SN, overall and in patients with palpable nodes, in those with non-palpable nodes and an AU leading to diagnosis of axillary involvement, in those with 1 or 2 suspicious nodes on AU, and in patients with a single suspicious node on AU. We evaluated clinical, imaging and pathology features as predictors of the status of the remaining axillary nodes, false-negatives, and false-positives. We included 25 patients in this phase. The false-negative rate of SN mapping was 28% overall, 21.42% for patients with palpable nodes, 36.36% for patients with non-palpable nodes and an AU diagnosis of axillary involvement, 28.75% for those with 1 or 2 suspicious nodes on AU, and 15.38% in patients with a single suspicious node on AU. The negative predictive value was highest in patients with a single suspicious node on AU (75%). The only significant predictive factor was that FN showed a higher Ki67 index score. In this study, SN mapping was not reliable in patients with biopsy-proven metastatic axillary nodes and upfront surgery for any of the subgroups studied. Further research should elucidate the best staging pathways in these patients to avoid premature de-escalation.

Value of Breast MRI and Nomogram After Negative Axillary Ultrasound for Predicting Axillary Lymph Node Metastasis in Patients With Clinically T1-2 N0 Breast Cancer.

There are increasing concerns about that sentinel lymph node biopsy (SLNB) could be omitted in patients with clinically T1-2 N0 breast cancers who has negative axillary ultrasound (AUS). This study aims to assess the false negative result (FNR) of AUS, the rate of high nodal burden (HNB) in clinically T1-2 N0 breast cancer patients, and the diagnostic performance of breast magnetic resonance imaging (MRI) and nomogram. We identified 948 consecutive patients with clinically T1-2 N0 cancers who had negative AUS, subsequent MRI, and breast conserving therapy between 2013 and 2020 from two tertiary medical centers. Patients from two centers were assigned to development and validation sets, respectively. Among 948 patients, 402 (mean age ± standard deviation, 57.61 ± 11.58) were within development cohort and 546 (54.43 ± 10.02) within validation cohort. Using logistic regression analyses, clinical-imaging factors associated with lymph node (LN) metastasis were analyzed in the development set from which nomogram was created. The performance of MRI and nomogram was assessed. HNB was defined as ≥ 3 positive LNs. The FNR of AUS was 20.1% (81 of 402) and 19.2% (105 of 546) and the rates of HNB were 1.2% (5/402) and 2.2% (12/546), respectively. Clinical and imaging features associated with LN metastasis were progesterone receptor positivity, outer tumor location on mammography, breast imaging reporting and data system category 5 assessment of cancer on ultrasound, and positive axilla on MRI. In validation cohorts, the positive predictive value (PPV) and negative predictive value (NPV) of MRI and clinical-imaging nomogram was 58.5% and 86.5%, and 56.0% and 82.0%, respectively. The FNR of AUS was approximately 20% but the rate of HNB was low. The diagnostic performance of MRI was not satisfactory with low PPV but MRI had merit in reaffirming negative AUS with high NPV. Patients who had low probability scores from our clinical-imaging nomogram might be possible candidates for the omission of SLNB.

Diagnostic Value of Axillary Ultrasound, MRI, and 18F-FDG-PET/ CT in Determining Axillary Lymph Node Status in Breast Cancer Patients.

Knowing axillary lymph node (ALN) status before surgery affects decisions about treatment modalities. Therefore, reliable, noninvasive diagnostic methods are important for determining ALN metastases. We aimed to accurately evaluate the patient's ALN status with noninvasive imaging modalities while making treatment decisions. Patients who received the axillary ultrasound (AUS), magnetic resonance imaging (MRI), or 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) imaging modalities and whose ALNs were confirmed histopathologically by fine needle aspiration cytology (FNAC), sentinel lymph node biopsy (SLNB), or ALN dissection (ALND) were included in the study. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of AUS for the detection of ALN metastases were 83%, 62%, 59.2%, 54.8%, and 79.1%, respectively. For MRI they were 86.1%, 75%, 68.5%, 51.6%, and 85.3%, respectively, and for 18F-FDG-PET/CT they were 78%, 53%, 56.2%, 51.4%, and 72.5%, respectively. ALNs were found to be metastatic in all patients who were reported positive in all three imaging modalities. ALN metastases were detected in 19 of 132 patients (false negativity, 14.3%) in whom AUS, MRI, and 18F-FDG-PET/ CT images were all reported as negative. In our study, we found that the diagnostic performance of MRI was slightly better than AUS and 18F-FDG-PET/CT. When we used imaging modalities together, our accuracy rate was better than when we used them alone. For accurate evaluation of axillary lymph nodes, imaging modalities should be complementary rather than competitive.

The extent of agreement between frozen and paraffin block data from axillary samples in patients with early-stage breast cancer

IntroductionPatients with early-stage breast cancer currently undergo sentinel lymph node dissection to evaluate the axillary region. Frozen tissue blocks are evaluated intra operatively and paraffin-embedded samples are studied postoperatively. We explored whether sentinel lymph node dissection adequately reflected axillary involvement (as revealed by the paraffin blocks) in patients with early-stage breast cancer; we sought to avoid axillary dissection. MethodsThe agreement/non-agreement rates between the results of axillary ultrasonography and biopsy, sentinel lymph node and axillary dissections, and frozen and paraffin block results, were retrospectively analyzed for 200 patients with early-stage breast cancer. The positive predictive values and accuracies were recorded in those who were positive on both ultrasonography and biopsy. The negative predictive values were calculated for doubly negative cases. ResultsThe frozen and paraffin block results disagreed in 19 (9.5 %) cases and agreed in 181 (90.5 %). The frozen block and dissection results differed in five of 38 patients who underwent axillary dissection (AD) (one patient did not undergo AD); the results were in agreement in 32. Of the 19 block-disagreement cases, 16 were in the non-neoadjuvant chemotherapy (NAC) group and three in the NAC treatment group. Clinically, the negative predictive values of the frozen and paraffin block data were 80 % in patients lacking axillary involvement. ConclusionParaffin block evaluations only (thus, without frozen block examinations) of early-stage breast cancer lymph nodes seem to be sufficient to guide treatment. Also, a thorough clinical examination (with ultrasonography and axillary biopsy) reduces the dissection rate and the associated functional impairments.

Axillary ultrasound after neoadjuvant therapy reduces the false-negative rate of sentinel lymph node biopsy in patients with cytologically node-positive breast cancer.

This study aimed to determine whether post-neoadjuvant therapy (NAT) axillary ultrasound (AUS) could reduce the false-negative rate (FNR) of sentinel lymph node biopsy (SLNB). We also performed subgroup analyses to identify the appropriate patient for SLNB. A total of 220 patients with cytologically proven axillary node-positive breast cancer who underwent both SLNB and axillary lymph node dissection (ALND) after NAT were included. We calculated the FNR of SLNB. In the case of post-NAT AUS results available, AUS was classified as negative or positive. Then the FNR of post-NAT AUS combined with SLNB was evaluated. Subgroup analyses based on the number of sentinel lymph nodes removed, molecular subtypes, and the clinical N stage were also performed. The overall axillary lymph node pathological complete response rate was 45.5% (100/220). The FNR of SLNB alone was 15.8% (95%CI: 9.2 to 22.5%). Post-NAT AUS results were available for 181 patients. When combined negative post-NAT AUS results and SLNB, the FNR was reduced to 7.5% (95%CI: 2.4 to 12.7%). Subgroup analyses of the FNR for SLNB alone and negative post-NAT AUS combined with SLNB were shown as follows: in cases patients with less than three sentinel lymph nodes (SLNs) and at least three SLNs removed, the FNR was decreased from 24.5 to 13.2%, and 9.0 to 5.0%, respectively. The FNR was decreased from 20.8 to 10.5% in HR+/HER2+subgroup, 21.4 to 16.7% in HR-/HER2+subgroup, 15.9 to 7.0% in HR+/HER2- subgroup, and 0% in HR-/HER2- subgroup, respectively. For cN1 patients, the FNR was decreased from 18.1 to 12.1% while 17.1 to 3.6% for cN2 patients and 0% for cN3 patients. Using negative post-NAT AUS may help to decrease the FNR and improve patient selection for SLNB.

Assessing Whether Morphological Changes in Axillary Lymph Node Have Already Occurred Prior to Metastasis in Breast Cancer Patients by Ultrasound.

Background and Objectives: Whether the morphological changes in axillary lymph node (ALN) have occurred prior to metastasis remains unclear in breast cancer (BC) patients. The aim of this study is to investigate the influence of BC for the morphology of non-metastasis ALN (N−) and, further, to improve the performance of ultrasound (US) examination for metastasis ALN (N+). Materials and Methods: In this retrospective study, 653 patients with breast mass were enrolled and divided into normal group of 202 patients with benign breast tumor, N− group of 233 BC patients with negative ALN and N+ group of 218 BC patients with positive ALN. US features of ALN were evaluated and analyzed according to long (L) and short (S) diameter, the (L/S) axis ratio, cortical thickness, lymph node edge, replaced hilum and color Doppler flow imaging (CDFI). Results: ALN US features of short diameter, replaced hilum, cortical thickness and CDFI have significant statistical differences in N− group comparing with normal group and N+ group, respectively (p < 0.05). Conclusions: Therefore, BC can affect ALN and lead to US morphological changes whether lymph node metastasis is present, which reduces the sensitivity of axillary US. The combination of US and other examination methods should be applied to improve the diagnostic performance of N+.

The Use of Machine Learning to Reduce Overtreatment of the Axilla in Breast Cancer: Retrospective Cohort Study.

Patients with early breast cancer undergoing primary surgery, who have low axillary nodal burden, can safely forego axillary node clearance (ANC). However, routine use of axillary ultrasound (AUS) leads to 43% of patients in this group having ANC unnecessarily, following a positive AUS. The intersection of machine learning with medicine can provide innovative ways to understand specific risks within large patient data sets, but this has not yet been trialed in the arena of axillary node management in breast cancer. The objective of this study was to assess if machine learning techniques could be used to improve preoperative identification of patients with low and high axillary metastatic burden. A single-center retrospective analysis was performed on patients with breast cancer who had a preoperative AUS, and the specificity and sensitivity of AUS were calculated. Standard statistical methods and machine learning methods, including artificial neural network, naive Bayes, support vector machine, and random forest, were applied to the data to see if they could improve the accuracy of preoperative AUS to better discern high and low axillary burden. The study included 459 patients; 142 (31%) had a positive AUS; among this group, 88 (62%) had 2 or fewer macrometastatic nodes at ANC. Logistic regression outperformed AUS (specificity 0.950 vs 0.809). Of all the methods, the artificial neural network had the highest accuracy (0.919). Interestingly, AUS had the highest sensitivity of all methods (0.777), underlining its utility in this setting. We demonstrated that machine learning improves identification of the important subgroup of patients with no palpable axillary disease, positive ultrasound, and more than 2 metastatically involved nodes. A negative ultrasound in patients with no palpable lymphadenopathy is highly indicative of low axillary burden, and it is unclear whether sentinel node biopsy adds value in this situation. Further studies with larger patient numbers focusing on specific breast cancer subgroups are required to refine these techniques in this setting.

81 (PB-081) Poster - Efficacy of pre-operative axillary ultrasonography in excluding nodal disease – can it replace sentinel lymph node biopsy in early stage breast cancer?

81 (PB-081) Poster - Efficacy of pre-operative axillary ultrasonography in excluding nodal disease – can it replace sentinel lymph node biopsy in early stage breast cancer?

The role of pre-operative axillary ultrasound in assessment of axillary tumor burden in breast cancer patients: a systematic review and meta-analysis.

Recent studies have suggested that a significant proportion of patients with axillary nodal metastases diagnosed by pre-operative axillary ultrasound (AUS)-guided needle biopsy were over-treated with axillary lymph node dissection (ALND). The role of routine AUS and needle biopsy in early breast cancer was questioned. This review aims to determine if pre-operative AUS could predict the extent of axillary tumor burden and need of ALND. PubMed and Embase literature databases were searched systematically for abnormal AUS characteristics and axillary nodal burden. Studies were eligible if they correlated the sonographic abnormalities in AUS with the resultant axillary nodal burden in ALND according to the ACOSOG Z0011 criteria. Eleven retrospective studies and one prospective study with 1658 patients were included. Sixty-five percent of patients with one abnormal lymph node in AUS and 56% of those with two had low axillary nodal burden. Using one abnormal lymph node as the cut-off, the pooled sensitivity and specificity in prediction of axillary nodal burden were 66% (95%CI 63-69%) and 73% (95% CI 70-76%), respectively. Across the six studies that evaluated suspicious nodal characteristics, increased nodal cortical thickness may be associated with high axillary nodal burden. More than half of the patients with pre-operative positive AUS and biopsy proven axillary nodal metastases were over-treated by ALND. Quantification of suspicious nodes and extent of cortical morphological changes in AUS may help identify suitable patients for sentinel lymph node biopsy.

Improved false-negative rates using a novel patient selection flowchart in initially biopsy-proven node-positive breast cancer undergoing blue-dye alone guided sentinel lymph node biopsy after neoadjuvant chemotherapy.

Current trials support the application of sentinel lymph node biopsy (SLNB) in node-positive breast cancer treated with neoadjuvant chemotherapy (NAC) with a lower false-negative rate (FNR) if dual-tracer (radioisotope and blue-dye) is used. However, radioisotopes are not available in many areas of the world. In this study, we evaluated the feasibility and accuracy of SLNB mapped with methylene-blue-dye alone. This study enrolled 132 patients with biopsy-proven node-positive breast cancer with a clip placed in the positive node who then received NAC. After chemotherapy and before operation, all patients underwent axillary ultrasound (AUS) assessment and were classified as either negative (AUS-) or positive (AUS +) according to the axillary status. All patients underwent both SLNB and axillary lymph node dissection (ALND). SLNB was mapped with methylene-blue-dye alone. FNRs were evaluated on factors potentially affecting false-negative SLN finding. Using methylene-blue-dye alone, the FNR of SLNB was 9.9%. Post-NAC AUS assessment (p = 0.009) and the number of SLNs retrieved (p = 0.029) showed association with FNRs in multivariate analysis. In AUS- group, FNR was as low as 2.5%. In AUS + group, retrieving ≥ 4 SLNs including the clipped node improved FNR from 17.1% to 4.8%. A flowchart was designed with the combination of post-NAC AUS assessment, retrieved SLN number, and the retrieved of clipped node further improve overall FNR to 3.3%. In biopsy-proven node-positive breast cancer treated with NAC, using a flowchart to optimize patient selection reduces the FNR of single-tracer (methylene-blue-dye) guided SLNB.

Rates of pathologic nodal disease among cN0 and cN1 patients undergoing routine axillary ultrasound and neoadjuvant chemotherapy.

Routine axillary ultrasound (AxUS) in patients receiving neoadjuvant chemotherapy (NAC) remains controversial. Here, we report rates of AxUS-detected nodal disease among patients with normal clinical exams, and rates of pathologic nodal disease after NAC based on method of nodal disease detection. Clinicopathologic findings were prospectively collected for stage I-III breast cancer patients selected for NAC. All patients had pre-treatment AxUS, suspicious nodes were biopsied. The following four patient cohorts were examined: patients with suspicious exam or AxUS but negative biopsy (Suspicious cN0); those with normal exam and normal AxUS (Not Suspicious cN0); those with normal exam but suspicious AxUS and positive biopsy (AxUS-detected cN1); and those with abnormal exam and positive biopsy (exam-detected cN1). Sentinel (SLN) and non-sentinel lymph nodes (non-SLN) were evaluated by immunohistochemistry; nodal metastases of any size were considered positive. 500 patients were included. Of 310 patients with normal axillary exams, 160 had suspicious AxUS, 65 were biopsy-negative (Suspicious cN0) and 95/310 (30.6%) were biopsy-positive (AxUS-detected cN1). Of 190 with abnormal axillary exams, 166 were biopsy-proven node-positive (exam-detected cN1) and 24 were AxUS or biopsy-negative (Suspicious cN0). Rates of pathologic nodal disease were 20/150 (13.3%) among Not Suspicious cN0 patients, 12/89 (13.5%) among Suspicious cN0 (p = 0.97). Rates of residual nodal disease were 55/95 (57.9%) among AxUS-detected cN1 patients, 102/166 (61.4%) among exam-detected cN1 (p = 0.57). AxUS detected nodal disease in 30.6% of patients with normal clinical exams selected for NAC. Rates of pathologic nodal disease were similar among AxUS-detected and exam-detected cN1 patients.

Axillary ectopic breast tissue in the adolescent.

Ectopic breast tissue (EBT) includes a spectrum of disease that entails other entities based on the presence of glandular tissue, nipple, or areola. The diagnosis in adolescents is infrequent. A retrospective study was performed including girls with axillary EBT (class IV or V of Kajava's Classification) operated in 2006-2020. Imagining studies, clinical and surgical reports, and histopathology were reviewed. Eleven girls from 13 to 16years old were included. Two patients (18.2%) presented bilateral EBT. The most frequent clinical manifestation was 2-5cm mass (100%), associating cyclic pain with menstruation (45%) and fluctuating volume (36%). Bilateral axillary ultrasonography allowed preoperative diagnosis. All of them were treated by open excision, through small incisions located in an axillary y fold. Clinical and aesthetic results were self-assessed as "very good", with normalization of the axillary y hollow and imperceptible scars. No recurrences were observed after one year of follow-up. An immediate postoperative hematoma was reported, which did not require drainage. Histopathology showed mature breast tissue without atypia. Axillary accessory breasts must be included in differential diagnosis of pediatric axillary masses. Bilateral ultrasonography is recommended for the preoperative diagnosis. Excision through minimal incision at this age seems to be safe and effective.

Unilateral axillary lymphadenopathy following COVID-19 vaccination

Objectives: COVID-19 vaccine effects on the lymph nodes of the axillary lymph nodes were examined in this study by comparing the characteristics of the nodes before and after immunisation. Methods: More than twenty-five employees who took part in the company's immunisation campaign were considered for employment. Before vaccination, one week after the first dose, and one week after the second dose, the ipsilateral vaccinated arm was examined by axillary ultrasonography. The total number of visible nodes, the maximum diameter and cortical measures, and Bedi's categorization were recorded. The Mann–Whitney U test was used to compare the collected data and determine the differences between the two groups. As long as the statistical significance threshold was met, the variables were regarded to be of interest to researchers. Results: There was a statistically significant increase in the number of visible nodes, maximal diameter, cortical thickness, and Bedi's classification grade (p 0.001) between the three US examinations. In comparison to patients who had previously been infected with COVID-19, those who were nave to the virus had a greater lymph node response.

Elaboration and Validation of a Nomogram Based on Axillary Ultrasound and Tumor Clinicopathological Features to Predict Axillary Lymph Node Metastasis in Patients With Breast Cancer.

BackgroundThis study aimed at constructing a nomogram to predict axillary lymph node metastasis (ALNM) based on axillary ultrasound and tumor clinicopathological features.MethodsA retrospective analysis of 281 patients with pathologically confirmed breast cancer was performed between January 2015 and March 2018. All patients were randomly divided into a training cohort (n = 197) and a validation cohort (n = 84). Univariate and multivariable logistic regression analyses were performed to identify the clinically important predictors of ALNM when developin1 g the nomogram. The area under the curve (AUC), calibration plots, and decision curve analysis (DCA) were used to assess the discrimination, calibration, and clinical utility of the nomogram.ResultsIn univariate and multivariate analyses, lymphovascular invasion (LVI), axillary lymph node (ALN) cortex thickness, and an obliterated ALN fatty hilum were identified as independent predictors and integrated to develop a nomogram for predicting ALNM. The nomogram showed favorable sensitivity for ALNM with AUCs of 0.87 (95% confidence interval (CI), 0.81–0.92) and 0.84 (95% CI, 0.73–0.92) in the training and validation cohorts, respectively. The calibration plots of the nomogram showed good agreement between the nomogram prediction and actual ALNM diagnosis (P > 0.05). Decision curve analysis (DCA) revealed the net benefit of the nomogram.ConclusionsThis study developed a nomogram based on three daily available clinical parameters, with good accuracy and clinical utility, which may help the radiologist in decision-making for ultrasound-guided fine needle aspiration cytology/biopsy (US-FNAC/B) according to the nomogram score.

111P Sentinel lymph node biopsy in post-neoadjuvant chemotherapy breast cancer patients using combination of fluorescein and blue dye versus blue dye alone: An interim analysis of a randomized controlled trial (SONAR-FB)

Sentinel lymph node biopsy (SLNB) is a standard procedure to determine the axillary lymph node(ALN) status in node-negative breast cancer(BC). Due to cost constraints and limited availability, the radiocolloid is being used in very few centers in developing countries. Fluorescein is inexpensive, sensitive fluorescent dye. SLNB in post neoadjuvant chemotherapy (NACT), has shown a higher false-negative rate (FNR) and lower identification rate(IR) comparing early BC. We studied the SLN IR and FNR of a dual tracer method, fluorescein plus methylene blue(FB) over methylene blue alone(B) in post NACT patients. It is a prospective, single-center, parallel-arm randomized controlled trial. All clinical node-negative, non-metastatic BC patients after NACT were included. They underwent axillary ultrasonography (AUS) to assess the morphologic appearance of the ALN to categorize it into normal or suspicious nodes. All patients were randomized before surgery. In one group, SLNB was done by FB and the other group by B alone after confirmation of non-allergy to the respective dye/dyes. All patients underwent ALN dissection. The primary objectives were SLN IR and FNR and the secondary objective was AUS's accuracy in the assessment of ALN pathological status. Out of 230 BC patients, 133 patients received NACT. Only 42 patients had clinically negative nodes after NACT. SLNB by FB and B was done in 21 patients and 20 patients, respectively. SLN could be identified in 20 out of 21 patients by the dual tracer(95%). Out of 20 patients, fluorescent nodes were identified in 19 (90.4%%) while blue nodes could be identified in 16 (76.1%). In the B group, Blue nodes were identified in 16/20 patients(80.0%).FNR with dual tracer was 11.1%(1/09 ) and FNR with blue dye was 16.6%( 1/06 ). AUS had 92% accuracy. A dual tracer. FB has a better IR and lowers FNR than B alone in post NACT breast cancer patients. It can be used as a low-cost and effective alternative to other dual tracers in low and middle-income countries.Moreover, excellent visualization of a lymphatic pathway by fluorescein can guide tracing the SLN.

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

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+). 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). 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. 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.

Axillary lymph node characteristics in breast cancer patients versus post-COVID-19 vaccination: Overview of current evidence per imaging modality

BackgroundAxillary lymph node characteristics on axillary ultrasound (US), breast MRI and 18F-FDG PET/CT are relevant at breast cancer diagnosis. Axillary lymphadenopathy after COVID-19 vaccination has been frequently reported. This may cause a diagnostic dilemma, particularly in the ipsilateral axilla in women who have a either a recent diagnosis of breast cancer or a history of breast cancer. This review provides an overview of the current evidence regarding axillary lymph node characteristics at breast cancer diagnosis versus “post-COVID-19 vaccination”. MethodsA non-systematic narrative review was performed. Studies describing axillary lymph node characteristics per imaging modality (axillary US, breast MRI and 18F-FDG PET/CT) in breast cancer patients versus post-COVID-19 vaccination were selected and used for the current study. ResultsThe morphologic characteristics and distribution of abnormal nodes on US may differ from the appearance of metastatic adenopathy since diffuse cortical thickening of the lymph nodes is the most observed characteristic after vaccination, whereas metastases show as most suspicious characteristics focal cortical thickening and effacement of the fatty hilum. Current evidence on MRI and 18F-FDG on morphologic characteristics of axillary lymphadenopathy is missing, although it was suggested that vaccine related lymphadenopathy is more likely to be present in level 2 and 3 nodes than metastatic nodes. Reported frequencies of lymphadenopathy post-COVID-19 vaccination range from 49% to 85% (US), 29% (breast MRI) and 14.5% to 53.9% (18F-FDG PET/CT). Several factors may impact the presence or extent of lymphadenopathy post-COVID-19 vaccination: injection site, type of vaccine (i.e., mRNA versus vector), time interval (days) between vaccination and imaging, previous history of COVID-19 pneumonia, and first versus second vaccine dose. ConclusionAlthough lymph node characteristics differ at breast cancer diagnosis versus post-COVID-19 vaccination, clinical information regarding injection site, vaccine type and vaccination date needs to be documented to improve the interpretation and guide treatment towards the next steps of action.

Role of shear wave elastography as an adjunct to axillary ultrasonography in predicting nodal metastasis in breast cancer patients with suspicious nodes.

To evaluate the role of shear wave elastography (SWE) of suspicious axillary lymph nodes and its combination with B-mode USG in predicting nodal metastasis in breast cancer patients. Prospective observational study was performed from June 2018 to August 2020 on breast cancer patients with suspicious axillary nodes on USG. B-mode features (cortical thickness, effacement of fatty hilum, non-hilar blood flow and round shape) and SWE parameters (Emax, Emin, Emean and ESD) of the node with the thickest cortex were evaluated. Diagnostic performances of USG, SWE and their combination were estimated using pathological status of the node on biopsy as the gold standard. Of the 54 patients evaluated, optimal elasticity maps were obtained in 49 nodes of 49 patients (mean age, 46.3 ± 12.1 years; 48/49 (98%) females). On biopsy, 38 nodes (77.6%) had metastasis, while 11 (22.4%) had reactive hyperplasia. Emax, Emin, Emean and ESD of both cortex and hilum were significantly higher in metastatic than reactive nodes. Emax (cortex) ≥14.9 kPa had the best diagnostic performance (sensitivity, 73.7%; specificity, 81.8%). Cortical thickness ≥6.7 mm had the best diagnostic performance among B-mode features (sensitivity, 89.5%; specificity, 72.7%). Combining cortical thickness with effacement of fatty hilum and/or non-hilar blood flow yielded sensitivity of 89.5% and specificity of 90.9%. Addition of Emax (cortex) to cortical thickness and combination of ≥2 B-mode features increased their specificities to 90.9 and 100%, respectively. Metastatic axillary nodes are stiffer than reactive nodes on SWE in breast cancer patients. Emax (cortex) has the best diagnostic performance in differentiating between reactive hyperplasia and nodal metastasis. Combination of Emax (cortex) and cortical thickness increases the specificity for diagnosing metastasis, especially in nodes showing only cortical thickening. Combination of SWE and B-mode USG is highly specific for differentiating metastasis from reactive hyperplasia in suspicious nodes of breast carcinoma patients, especially in nodes with only cortical thickening.

Preoperative axillary ultrasonography in patients with breast cancer: a prospective study to evaluate its ability to predict axillary tumor load

ObjectiveThis study aimed to determine the ability of axillary ultrasonography to predict the number of lymph nodes with metastases found in sentinel node axillary surgery or axillary lymph node resection in patients recently diagnosed with breast cancer after percutaneous biopsy. MethodsThis prospective study included patients diagnosed with invasive breast cancer by percutaneous biopsy. Axillary lymph nodes were classified at ultrasound examination as suspicious or not suspicious, and the number of suspicious nodes was compared with the number classified as suspicious in the surgical specimen. ResultsWe included 142 patients, 4 of whom had bilateral cancer; 133 of the 146 tumors were clinically classified as T1-T2 N0. The median number of suspicious lymph nodes at ultrasound was 2 (1–6), and the median number of suspicious lymph nodes in the surgical biopsy specimen was 1 (1–16); the difference was not significant (p = 0.1). The correlation between the number of positive lymph nodes on axillary ultrasound and the number of metastatic lymph nodes in the surgical specimen was 72.7% p = 0.0002 and the concordance was 79% (95%CI 62.4%–95.6%) p = 0.0001. For diagnosing high axillary tumor load (≥3 metastatic lymph nodes) versus low axillary tumor load (<3 metastatic lymph nodes), axillary ultrasound had 86.6% sensitivity, 83.3% specificity, 92% PPV, and 71.4% NPV. ConclusionOur results show that preoperative axillary ultrasound can differentiate between low and high tumor load and can be used as a tool to select the type of treatment. These results need to be confirmed in randomized multicenter studies.

Abstract P1-01-11: Axillary extensive burden evaluation by ultrasound in preoperative nodal staging in breast cancer patients

Abstract Purpose :Since ACOSOG Z1011 trial, the role of axillary US preoperative has been redirected for predicting extensive axillary involvement. Our study is aimed to evaluate routinely US axillary prediction for extensive nodal burden in breast cancer. Materials and methods :The study was approved by the institutional reaview board and the requirement for in-formed consent was waived.All patients in our institution with early-stage invasive breast cancer have a systematic axillary ultrasound (US) evaluation before surgery.A prospective study of radiology and pathology records concerns all consecutives patients to evaluate US correlation with surgical findings beetwen November 1, 2020 and July 15, 2021.Neoadjuvant chemotherapy, ductal carcinoma in situ on breast biopsy, and relapse cases were excluded.Criteria used to define abnormal lymph nodes included : focal or diffuse cortical thickening with cortex thicker than &amp;gt;4mm, replacement or effacement of the fatty hilium, or rounder lymph node.3 US prediction groups were defined as: US G0 normal (no suspicious lymph node) ;US G1 non extensive involvement (1 or 2 suspicious nodes) ; US G2 extensive involvement (≥3 suspicious nodes).In case of preoperative positive axillary biopsy, positive intraoperative examination, or patients without Acosog criteria, an axillary dissection was systematically performed.3 pathologic groups were defined as : path G0 (pN0) ; path G1 (≤2pN+) ; path G2 (≥3pN+).Statiscal analysis was performed with the chi-square the Fisher’s exact test.NPV for extensive axillary burden is defined as the proportion of patients with a negative test result (US G0 or US G1) that does not have extensive nodal involvement histologically (path G0 or path G1). Results. The study is still ongoing. On the 241 first cases, 64.3% (155/241) were cT1, 82.9% (200/241) were cN0. 163(78.3%) had Ductal invasive carcinoma, 37 were lobular histologic characteristics (17.8%) and 8 were mixted (3.8%).6.2% (15/241) patients presented extensive nodal involvement. ConclusionThe results of this study are preliminary. They will be completed after the next study closure. In the first results, it is globally observed that the preoperative ultrasound makes it possible to exclude more than 97% of extensive involvement (&amp;gt;2pN+). In case of less than 3 US suspected axillary nodes , sentinel node biospy remains indicated. The false negative rate cannot be calculated on this day and will not be presented until later. Path G0Path G1Path G2totalUS G0156243187US G1310922US G20033total1593415241VPN for extensive nodal disease is 97.9% (193/197).In abnormal US groups (US G1+US G2), 48% (12/24) patients had extensive axillary involvement. Citation Format: Camille Defoort, Joanna Chemaly, Luc Ceugnart, Marie-Pierre Chauvet. Axillary extensive burden evaluation by ultrasound in preoperative nodal staging in breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-01-11.