Suspicious Nodes Research Articles

Intraoperative ultrasound guided wire (IOUS-wire) localization biopsy with frozen section versus preoperative fine needle aspiration cytology (FNAC) for the evaluation of clinically positive nodes in patients with early breast cancer in China real-world clinical practice.

e12600 Background: Appropriate biopsy procedure for clinically positive (suspicious) lymph nodes (LN) plays a key role in accurate axillary staging of early breast cancer. Fine needle aspiration (FNA) is a recommended method for clinically suspicious nodes in the National Comprehensive Cancer Network (NCCN) guidelines. However, the false negative rate (FNR) of FNA remains too high. Therefore, it is valuable to explore an alternative and appropriate procedure in clinical practice. We conducted a retrospective review to compare the feasibility and diagnostic efficiency of using a novel procedure, the intraoperative ultrasound guided wire (IOUS-wire) localization biopsy with frozen section, to FNA for assessment of clinically positive nodes in patients with early breast cancer. Methods: Data on consecutive primary breast cancer patients with documented axillary ultrasound results who had clinically positive lymph nodes (cN1) between January 2015 and September 2023 either utilization of IOUS-wire localization or ultrasonography-guided fine-needle aspiration cytology (US-FNAC) for clinically positive lymph nodes were retrospectively analyzed. Sentinel lymph node biopsy (SLNB) was performed in patients with negative histopathological or cytological results. The false negative rate (FNR) of histopathology between two groups was calculated. Results: Eligible patients (n=198) referred to axillary biopsy by IOUS-wire localization biopsy(n=100) and US-FNAC(n=98) in this study. The FNR of clinically positive lymph nodes biopsy was 12.8 percent in the IOUS-wire localization group and 87.5 percent in the US-FNAC group.IOUS-wire failed in 5 patients. Among the remaining 32 successful identifications, 26 were IOUS-wire-node positive by intraoperative frozen section. 42 patients with additional lymph node metastases were found in FNAC-LN-negative patients by SLNB. The accuracy rate was respectively 95% and 57.1%. No significant difference was observed in complications and median number of SLNs harvested (5.3 versus 5.5; P=0.631) between the groups. Sufficient tissue samples can be obtained for intraoperative frozen pathology so the FNR is potentially reduced. In addition, the interval of waiting time for pathological results is reduced. Conclusions: Intraoperative US-guided wire localization biopsy is a feasible and alternative procedure compared to preoperative FNA for clinically node-positive patients with early breast cancer. This novel method is suitable for China's national conditions and should be further pursued as a potential biopsy method for evaluation of axillary node status in clinical practice.

Awareness, Knowledge, and Current Practice of Breast Cancer Among Surgeons in Jordan.

Breast cancer (BC) is the most prevalent cancer in Jordan. De-escalation in treatment reflects a paradigm shift in BC treatment. More tailored strategies and the adoption of a multidisciplinary approach are essential to apply recent changes in management. In the era of breast surgery fellowship, adopting well-structured training is essential to apply recent therapeutic guidelines and meet patients' expectations. A cross-sectional study using a customized, self-reported questionnaire was used. Data collection occurred anonymously using a link via WhatsApp in the period between February 2023 and April 2023. A total of 89 surgeons were involved in this study, and only 14 (15.7%) completed a subspecialty in breast surgery. About 58.4% considered the age of 40 years as the starting point for screening, and 84.3% reported that mammogram screening is associated with improved BC survival. Only 10.1% and 28.1% acknowledged the applicability of both tomosynthesis and breast magnetic resonance imaging in screening, respectively. A significant difference in the mean knowledge score about BC is observed between general surgeon and those with subspecialty. Varying levels of awareness concerning different risk factors and their correlation with the likelihood of BC occurrence observed. Although 56.2% of participants could offer breast conserving surgery and consider it oncological safe, only 48.3% defined it correctly. Of the participants, 61.8% and 76.4% stated that sentinel lymph node biopsy can be safely applied in clinically negative or suspicious axillary nodes, respectively, with <50% of surgeon performing it in their practice. More efforts are required to enhance the knowledge and practice of surgeons in the field of breast surgery. Adopting national guidelines can facilitate the acceptance and improvement of current practices among surgeons in Jordan.

ESORES-Trial: Surgery as needed versus surgery on principle in patients with postneoadjuvant clinical complete tumor response of esophageal cancer.

TPS4185 Background: A substantial fraction of patients with esophageal cancer (EC) shows post-neoadjuvant pathological complete response (pCR). Principal esophagectomy after neoadjuvant treatment is the standard of care for all patients. Active surveillance (AS) and surgery as needed may be a treatment alternative for patients with clinical complete response (cCR). Methods: ESORES is a multicenter randomized controlled parallel-group non-inferiority trial. Patients are randomized either to surgery on principle and subsequent follow-up (Arm B) or clinical response evaluation (CRE) and surgery as needed (Arm A). CRE consists of esophagogastroscopy with deep biopsies (EGD), endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) of suspicious lymph nodes, and F18-FDG-PET CT. In case of residual tumor (non-CR) after CRE, treatment is surgery. Patients with cCR will proceed with AS and surgery only if local regrowth occurs. AS comprises EGD, EUS-FNA and CT-Thorax/Abdomen at 3/6/9/12/18/24 months and yearly thereafter. A sample size of 670 patients is needed to demonstrate non-inferiority of Arm A vs. Arm B with regard to overall survival (OS) at a one-sided significance level of 5%, choosing a hazard ratio of 1.325 as non-inferiority margin which corresponds to a difference in 3-year OS rates of 8%. Superiority with regard to quality of life will be evaluated hierarchically only after non-inferiority with respect to OS has been shown. Key inclusion criteria: histologically verified EC, TNM stage ycT0-3 ycN0 ycM0, completion of neoadjuvant chemotherapy (nCT) or chemoradiation (nCRT) (irrespective of specific protocol), no visible lymphatic or distant metastasis in routine postneoadjuvant CT. Key exclusion criteria: postneoadjuvant dysphagia and/or esophageal obstruction, tumors of the cervical esophagus, tumors with direct proximity to the membranous part of the central airways (if regrowth is suspected to evoke locally irresectable ryT4b-stage), TNM stage cT4/ycT4 and/or cM1/ycM1, tumor progression during/after nCT/nCRT, and nCRT with &gt;50 Gy radiation dose. Primary endpoints (hierarchically tested): 1) OS, 2) EORTC QLQ C30 global quality of life subscale. Secondary endpoints: Efficacy: long term tumor control, disease free survival, distant metastasis/local recurrence/regional recurrence; quality of life: EORTC QLQ C30, QLQ OES18, fear of progression: FoP-Q-12, surgery-free survival time in Arm A, patients’ satisfaction: EORTC OUT-PATSAT7; economic impact: days and costs of hospitalization; Safety: Interventional Safety: 3-Year-Comprehensive Complication Index, Oncological Safety (diagnostic accuracy of CRE, resection status (R0/R1/R2), irresectable regrowth during AS). Enrollment of patients started on January 30th, 2024. Clinical trial information: DRKS00032613 .

A nomogram to predict the risk of axillary upstaging in patients with Z0011-eligible breast cancer.

e12606 Background: ACOSOG Z0011 trial showed that in early cT1-2N0 breast cancer patients with 1-2 positive lymph nodes in sentinel lymph node biopsy (SLNB) can safely omit axillary lymph node dissection (ALND) without compromising local control and long-term survival. Although it is widely accepted worldwide, controversy and concerns remain that the incidence of non-sentinel lymph node metastasis may lead to pathological lymph node (pN) upstaging and insufficient systemic treatment. This study aims to identify risk factors for having ≥4 metastatic lymph node (pN2-3) in patients who met Z0011 criteria and received SLNB. Methods: This is a retrospective study enrolled 733 cT1-2N0 breast cancer patients with 1-2 positive SLNs treated between 2011-2022 at Sun Yat-sen Memorial Hospital. All patients had received SLNB followed by ALND. Patients included were divided into the training and validation sets at a 7:3 ratio. Differences were compared between pN1(1-3 LN+) and pN2-3(≥4 LN+) in training set using either t test or chi-squared test. Multivariate logistic regression was conducted to identify risk factors for pN upstaging and to form the basis of a predictive nomogram. The validation was processed in the other validation set and nomogram performance was evaluated using the area under ROC curve (AUC). Results: Among the 733 patients enrolled, 127 (17.3%) patients had pN upstaging (pN2-3) after ALND. There was a big difference of pN upstaging between the patients with 1 (47/511, 9.2%) and 2 (80/222, 36%) positive SLNs. 488 patients were allocated to the training set, among which 18.2% had pN upstaging. In univariate analysis, pN were differed by cT stage, axillary ultrasound appearance, histological grade, molecular subtype, Ki67, lymph vascular invasion, pathological tumor size, SLN metastasis type (micrometastasis or macrometastasis), positive SLN numbers and negative SLN numbers. Multivariate logistic analysis resulted six independent risk factors associated to pN upstaging: ultrasound suspicious node (OR=1.93; 95% CI: 1.08-3.47), positive lympho-vascular invasion (OR=2.27; 95% CI: 1.25-4.13), larger tumor size (OR=2.07; 95% CI: 1.15-3.73), SLN macro-metastasis (OR= 9.15; 95% CI: 1.07-78.13), two positive SLNs (OR= 6.59; 95% CI:3.70-11.76) and less negative SLN number (OR=1.54; 95% CI: 1.22-1.89). These factors were used to construct a predictive nomogram, exhibiting excellent performance with AUC values of 0.819 and 0.827 in the training and validation cohorts respectively. Conclusions: The Z0011-eligible patients with two positive SLNs may have a high risk of pN upstaging and need to be cautious to spare ALND. A practical nomogram is helpful to identify patients at high risk of pN upstaging and avoid insufficient systemic treatment.

Prognostic impact of suspicious extraabdominal lymph nodes on patient survival in advanced ovarian cancer.

To evaluate the clinical impact of suspicious extra-abdominal lymph nodes (EALNs) identified preoperatively on CT and/or PET/CT images in advanced ovarian cancer. A retrospective study was conducted with 122 patients diagnosed with stage III or IV ovarian cancer with preoperative CT and/or PET/CT images from 2006 to 2022. Imaging studies were evaluated for the presence, size and location of suspicious EALNs. Suspicious lymph node enlargement was defined by a cut-off ≥5mm short-axis dimension on CT and/or lesions with maximum standardized uptake values of ≥2.5 on PET/CT. This study only included patients who did not have their EALNs surgically removed. A total 109 patients met the inclusion criteria; 36 (33%) had suspicious EALNs and were categorized as "node-positive". The median overall survival (OS) was 45.73 months for the "node-positive" and 46.50 months for the "node-negative" patients (HR 1.17, 95% CI 0.68-2.00, p = 0.579). In multivariate analysis, after adjusting for other variables selected by process of backward elimination using a significance level of p<0.20, suspicious EALNs still showed no clinical significance on OS (aHR 1.20, 95% CI 0.67-2.13, p = 0.537) as well as progression-free survival (aHR 1.43, 95% CI 0.85-2.41, p = 0.174). Old age (aHR 2.23, 95% CI 1.28-3.89, p = 0.005) and platinum resistance (aHR 1.92, 95% CI 1.10-3.36, p = 0.023) affects adversely on OS. Suspicious EALNs did not worsen the prognosis of patients with advanced ovarian cancer. However, its impact on survival is not yet clarified. Further investigation is required to assess the clinical significance of suspicious EALNs on preoperative imaging studies.

Impact of ultrasound elastography in evaluating Bethesda category IV thyroid nodules with histopathological correlation.

Fine needle aspiration (FNA) is the gold standard method recommended in the diagnosis of thyroid nodules. Bethesda IV cytology results are identified in 7-9% of nodules investigated through FNA, with reported malignancy rate in a wide range of 10-40%. The recommended treatment is either surgical or risk additional molecular testing before surgery. However, a large number of nodules belonging to this category (60-80%) are observed to be benign after surgical excision, which can put the patient at risk of unnecessary surgical morbidity. This study aimed to assess the diagnostic performance of conventional ultrasound, the ACR TI-RADS score and elastography in cases of Bethesda IV cytology on FNA. We evaluated ninety-seven consecutive cases with Bethesda category IV results on FNA by using conventional B-mode ultrasound, qualitative strain or shear-wave elastography (Hitachi Preirus Machine, Hitachi Inc., Japan and Aixplorer Mach 30 Supersonic Imagine, Aix-en-Provence, France) and all nodules were classified according to the ACR TI-RADS system. Conventional ultrasound was used to categorize the nodules as potentially malignant based on the following features: hypoechogenicity, inhomogeneity, a taller than wide shape, irregular margins, presence of microcalcifications, an interrupted thyroid capsule and suspicious cervical lymph nodes. Elastography classified nodules with increased stiffness as suspicious for malignancy. We considered pathology results as the gold standard diagnosis, finding that 32 out of 97 nodules were carcinomas (33%) and 65 out of 97 were benign nodules (67%). The benign group included twenty cases of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). Finally, we compared ultrasound data with pathology results, which showed that nineteen out of the 32 malignant nodules presented with increased stiffness on elastography (p=0.0002). On conventional ultrasound, we found that microcalcifications (p=0.007), hypoechogenicity and irregular margins (p=0.006) are features which can distinguish between benign and malignant nodules with statistical significance. Integrating elastography as a parameter of the ACR TI-RADS score in the evaluation of Bethesda category IV nodules showed a sensitivity of 90.62% in detecting thyroid cancer cases (p=0.006). We can conclude that elastographic stiffness as an addition to high risk features observed on conventional ultrasound improves the detection of malignant nodules in cases with Bethesda IV cytology.

SCOUT® Radar Localization at Time of Breast Biopsy.

Evaluate surgical utilization of SCOUT reflectors placed at breast biopsy. Consent was waived for this retrospective IRB-approved, HIPAA-compliant study. Breast biopsy examinations that reported the term "SCOUT" between January 2021 and June 2022 were identified using an institutional search engine. Cases were included if a SCOUT reflector was placed at time of breast biopsy and excluded if lesion pathology was already known. Analysis was performed at the lesion level. A multivariate-regression analysis evaluated 6 variables with potential impact on SCOUT utilization. One hundred twenty-one lesions in 112 patients met inclusion criteria. Biopsy yielded 93% (113/121) malignant, 3% (4/121) elevated risk, 2% (2/121) benign-discordant, and 2% (2/121) benign-concordant results. Two cases lost to follow-up were excluded. SCOUT reflectors were utilized for lumpectomy (58%, 69/119 lesions) and excisional biopsy (6%, 7/119 lesions). SCOUTs were not utilized due to mastectomy (23%, 27/119), subsequent wire localization (2%, 2/119), and nonsurgical cases (12%, 14/119). Reflector placement utilization was 52% higher for findings less than 3.5 cm in size (P <.001), 33% higher in patients without prior treated breast cancer (P = .012), and 19% higher in patients with no suspicious ipsilateral lymph node (P = .048). SCOUT reflector placement at time of biopsy was utilized for surgery 64% (76/119) of the time, although most (98%, 119/121) biopsies were malignant, elevated risk, or benign-discordant. Factors increasing reflector utilization include smaller lesion size, no suspicious ipsilateral lymph node, and no prior treated breast cancer.

Long-term follow-up results of prostate capsule-sparing and nerve-sparing radical cystectomy with neobladder: a single-center retrospective analysis

ObjectiveThis study aims to investigate and analyze the feasibility, oncological outcomes, functional efficacy, and complications with the prostatic capsule sparing (PCS) as well as the nerve sparing (NS) in radical cystectomy for bladder cancer.Patients and methodsBetween January 2007 and December 2021, 67 total cystectomies with PCS and 54 with NS were performed at our institution. The inclusion criteria for PCS were as follows: proactive, fully informed patient consent; negative transurethral resection of the bladder neck; normal prostate-specific antigen (PSA) level &amp;lt; 4 ng/dL; and normal transrectal ultrasonography with biopsy of any suspicious nodes. Patients received complete oncological and functional follow-ups. The Kaplan-Meier method was utilized to characterize survival outcomes after surgery.ResultsThe median follow-up times for PCS and NS were 144 and 122 months, respectively. Cumulative survival estimated the 5- and 10-years cancer-specific survival were 93.0% and 88.7% for the PCS group and 79.7% and 79.6% for the NS group, respectively (p = 0.123). In terms of function, the daytime urinary control at 3, 6, and 12 months postoperatively was 80.60%, 97.01%, and 100% in the PCS group, and 53.70%, 85.19%, and 94.44% in the NS group, respectively (p = 0.002, 0.023, and 0.100); and nocturnal urinary control was 62.69%, 94.03%, and 98.51% in the PCS group, and 40.74%, 72.22%, and 87.04% in the NS group, respectively (p = 0.016, 0.001, and 0.022). The erectile function recovery revealed that 62.69% and 40.74% of patients returned to preoperative levels (International Index of Erectile Function (IIEF)-5 score ≥ 15) in the PCS and NS groups, respectively (p = 0.016). Considering complications within 30 days after surgery, 4.48% and 7.69% patients had Clavien ≥ III complications in the PCS and NS groups, respectively (p = 0.700).ConclusionThe PCS provides better restored urinary control and sexual function than the NS technique and does not affect oncological outcomes. However, PCS is prone to bladder-neck obstruction complications and requires closer long-term follow-up.

Sentinel lymph node detection with indocyanine green and patent blue dye in cervical cancer: A single-centre feasibility study.

Sentinel lymph node (SLN) dissection has been established as standard of care in many tumours. Its use in early cervical cancer is an area of increasing interest and some studies suggest a high detection rate. To explore feasibility of SLN dissection and establish the patient detection rate in women with early cervical cancer. All patients with early cervical cancer, International Federation of Gynaecology and Obstetrics (FIGO) 2018 Stage 1, of any histology who underwent SLN dissection from January 2017 to March 2023 were included. Patients were eligible if they had pelvic confined disease; no suspicious lymph nodes on pre-operative imaging or intra-operatively; tumours <4 cm at the time of surgery and no contra-indications to surgery. Patients were excluded if there was a known allergy to dye or less than six months follow-up data. Sixty-two patients were included in the study and 53% had FIGO stage 1b1 disease. The overall bilateral SLN detection rate was 89%, and the side-specific rate was 94%. Where indocyanine green (ICG) was used alone, the bilateral detection rate was 87% and the side-specific rate was 93%. Where ICG was used with patent blue dye (PTB) the bilateral detection rate was 92% and the side-specific rate was 96%. Where PTB was used alone the bilateral detection rate was 85% and the side-specific rate was 92%. The node positive rate was 6% (7/124) which included isolated tumour cells in four patients. SLN dissection with ICG or PTB is feasible in early-stage cervical cancer.

Active surveillance is a feasible and safe strategy in selected patients with papillary thyroid cancer and suspicious cervical lymph nodes detected after thyroidectomy.

After initial treatment, up to 30% of patients with papillary thyroid cancer (PTC) have incomplete response, mainly cervical lymph node (LN) disease. Previous studies have suggested that active surveillance (AS) is a possible option for these patients. Our aim was to report the results of AS in patients with PTC and cervical LN disease. In this retrospective observational study, we included adult patients treated and followed for PTC, who presented with cervical LN disease and were managed with AS. Growth was defined as an increase ≥ 3mm in either diameter. We included 32 patients: 27 (84.4%) women, age of 39 ± 14 years, all initially treated with total thyroidectomy, and 22 (69%) with therapeutic neck dissection. Cervical LN disease was diagnosed 1 year (0.3-12.6) after initial management, with a diameter of 9.0 mm (6.0-19.0). After a median AS of 4.3 years (0.6-14.1), 4 (12.5%) patients had LNgrowth: 2 (50%) of whom were surgically removed, 1 (25%) was effectively treated with radiotherapy, and 1 (25%) had a scheduled surgery. Tg increase was the only predictive factor of LN growth evaluated as both the delta Tg (p < 0.0366) and percentage of Tg change (p < 0.0140). None of the included patients died, had local complications due to LN growth or salvage therapy, or developed distant metastases during follow-up. In selected patients with PTC and suspicious cervical LNs diagnosed after initial treatment, AS is a feasible and safe strategy as it allows effective identification and treatment of the minority of patients who progress.

Évaluation du creux axillaire en 2024 : point de vue du chirurgien et rôle du radiologue

For patients with breast cancer, de-escalation of armpit surgical treatments happened during the last twenty years to reduce the morbidity mainly induced by complete axillary lymph node dissection, with a broadening of sentinel lymph node biopsy indications and, more recently, the development of targeted lymph node excision, with no impact on patient survival. Axillary ultrasound combined with clinical examination can predict the tumour burden in the axilla. At the same time, the radiologist's role has evolved, as they must describe the number of suspicious lymph nodes, which determines surgical management. Patients having fewer than two suspicious lymph nodes are eligible for sentinel lymph node biopsy. Ultrasound-guided fine-needle aspiration or core biopsy will provide proof of lymph node involvement.

Abstract PO4-22-10: Prognostic impact of preoperative lymph node diagnostic tools for patients with suspicious node positive breast cancer

Abstract (Abstract) Recently, the SOUND trial demonstrated the feasibility for omission of sentinel lymph node biopsy (SNB) in cases with negative ultrasound (US)-guided fine-needle aspiration cytology (FNA) of suspicious lymph nodes (LNs). An important consideration for omission of SNB depends on a highly accurate assessment of preoperative staging for axillary LNs. (Purpose) The purpose of this study was to investigate the impact of preoperative diagnostic tools for axillary lymph nodes (LNs) staging of early breast cancer. (Materials and Methods) A total of 3088 consecutive patients with operable breast cancer were retrospectively identified at our institution between April 2013 and March 2020. Patients with suspicious axillary LN of breast cancer were assessed using preoperative US and computed tomography (CT), underwent FNA or core needle biopsy (CNB). The inclusion criteria for both FNA and CNB were a cortical thickness [3 mm or abnormal morphological characteristics. Patients with biopsy-proven metastasis underwent axillary lymph node dissection (ALND), and those with a negative FNA or CNB underwent SNB. If the SNB was positive, ALND was performed. Diagnostic accuracy for SNB was calculated for both FNA and CNB. In addition, the patients in this study were divided into two groups as follows: the cN0-FNA negative group (suspicious LN but negative FNA) and the cN0-CNB group (suspicious LN but negative CNB). Overall survival (OS)and invasive disease survival(iDFS) was estimated by using the Kaplan-Meier method and compared by using the log-rank test. (Results) A number of patients with negative or suspicious metastasis US/CT findings of LNs were 3187, with 963 undergoing FNA and 395 undergoing CNB for suspicious LNs. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 63, 99, 99, 73, and 81% in FNA, and 87, 100, 100, 91 and 95% in CNB, respectively. SNB was performed in 207 (cN0-CNB group) of 395 CNB and 581 (cN0-FNA group) of 963 FNA patients. Two hundred and seven patients from the cN0-CNB group (T1ab; 42, T1c; 72, T2;84, T3;9 patients) treated with SNB were compared to 581 from the cN0-FNA group (T1ab;86, T1c;193, T2;278, T3;24 patients) in terms of number of LN metastasis. A number of patients with micrometastases, 1,2,3 or more than 4 positive LNs were 5(2%),7(3%),3(1%)9,3(1%) and 0 (0%) in cN0-CNB group, and 23(4%),67(12%),26(4%),12(2%) and 29 (5%) in cN0-FNA group, respectively. The significant difference in 5ys iDFS and OS was observed between CNB group and FNA group (94.2% vs.91.4%, p =0.04 and 99% vs. 95%, p=0.004, respectively). Conclusions The preoperative diagnosis of axillary LNs was influenced by the diagnostic tool used. CNB is a reliable method for the preoperative diagnosis of LN metastasis. The prognosis of early breast cancer with clinically metastasis-negative lymph nodes diagnosed by CNB is better than that by FNA. Table. Number of positive lymph nodes cN0-FNA (%) cN0-CNB (%) Total 207 100 581 100 0 189 91 424 73 micrometastasis 5 2 23 4 1 7 3 67 12 2 3 1 26 4 3 3 1 12 2 4 more than 0 0 29 5 Citation Format: Rikiya Nakamura, Shouko Hayama, Rikiya Nakamura, Naohito Yamamoto. Prognostic impact of preoperative lymph node diagnostic tools for patients with suspicious node positive breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-22-10.

Abstract GS02-06: Recurrence-free survival following sentinel node-positive breast cancer without completion axillary lymph node dissection – first results from the international randomized SENOMAC trial

Abstract Background The omission of a completion axillary lymph node dissection (cALND) after a positive sentinel lymph node (SLN) biopsy in patients with clinically node-negative breast cancer has been demonstrated to yield survival outcomes non-inferior to routine cALND in breast-conserving surgery followed by whole-breast irradiation (ACOSOG Z0011 and IBCSG 23-01 trials), and to axillary radiotherapy (RT) regardless of breast surgery (EORTC AMAROS trial). Mainly due to the under-representation of mastectomy patients, and a limited number of observed events compromising statistical power, the international randomized SENOMAC trial was initiated in 2015. The main aim of this non-inferiority trial was to address knowledge gaps relating to individuals treated by mastectomy, those with larger tumors and those with SLN extracapsular extension. Method The SENOMAC trial (NCT 02240472) enrolled patients with cT1-3cN0 primary breast cancer and 1-2 SLN macrometastases at 67 sites in five countries between January 27, 2015, and December 31, 2021. Participants were randomized 1:1 between cALND (standard) and omission of cALND (intervention). Stratification was per country. Breast-conserving surgery and mastectomy were eligible surgical interventions. Preoperative axillary ultrasound was mandatory; patients with non-palpable suspicious axillary lymph nodes, even if proven metastatic by biopsy, were eligible. SLN extracapsular extension was allowed. Adjuvant radiotherapy was dictated by national guidelines and not by the trial protocol. Statistical sample size calculation was based on the primary outcome overall survival. Non-inferiority was defined as a 5-year overall survival not worsened by more than 2.5% when refraining from cALND after the observation of 190 all-cause deaths in a target sample size of 3000 included patients. In the present analysis, the pre-specified secondary outcome of recurrence-free survival is reported. Results Out of 2766 randomized individuals, 2539 comprised the per-protocol population: 1204 in the standard and 1335 in the intervention group. Median follow-up was 37.1 months (1.5-75.0) and median age at inclusion 61 years (range 20-94). Most tumors belonged to the luminal subtype (93.6%); tumor stage was T1 in 1358 (53.5%), T2 in 1034 (40.7%) and T3 in 146 participants (5.8%). Out of 347 participants with suspicious lymph nodes on ultrasound, 36 had confirmed non-palpable metastasis. SLN extracapsular extension was reported in 866 (34.1%). The breast was conserved in 1621 (63.8%) and a mastectomy performed in 918 (36.2%) patients. Most patients (2127, 83.8%) received radiotherapy including nodal target volumes. In 34.1% of the standard group, additional non-SLN metastases were identified on cALND. Overall, 104 recurrences were reported, 54 (4.5%) in the standard and 50 (3.7%) in the intervention group. Of these, 11 recurrences were found in the ipsilateral axilla: 5 (0.4%) and 6 (0.5%), respectively. Recurrence-free survival did not differ between groups (country-adjusted HR 0.89, 95% CI 0.65-1.20). Conclusion Despite extended inclusion criteria, there was no difference in recurrence-free survival whether cALND was omitted (intervention) or not (standard). Patients undergoing mastectomy will specifically be addressed in subgroup analyses. Long-term follow-up is crucial considering the high proportion of luminal cancers. Citation Format: Jana de Boniface, Tove Tvedskov, Bergkvist Leif, Jan Frisell, Yvette Andersson, Sara Alkner, Malin Sund, Roger Olofsson Bagge, Dan Lundstedt, Oreste Davide Gentilini, Michalis Kontos, Toralf Reimer, Birgitte Offersen, Thorsten Kühn, Lisa Rydén, Peer Christiansen. Recurrence-free survival following sentinel node-positive breast cancer without completion axillary lymph node dissection – first results from the international randomized SENOMAC trial [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr GS02-06.

Abstract PS05-03: MagSense® HER2, a Molecularly Targeted Magnetic Resonance Imaging Agent for the Detection of Axillary Nodal Metastasis in Subjects with Human Epidermal Growth Factor Receptor 2 Positive (HER2+) Breast Cancer

Abstract Background Precise nodal staging is critical in guiding systemic and regional treatments including surgery in the management of breast cancer. Regional nodal assessment includes axillary imaging (mostly by ultrasound) and lymph node sampling. Since imaging findings suggestive of nodal metastasis are based on size and morphologic changes and not specific to tumor type, pathologic confirmation through either biopsy or removal of sentinel lymph node (SLN) remains the gold standard. Imagion is developing the MagSense® HER2 Imaging Agent (MSH2IA), an anti-human epidermal growth factor receptor 2 (HER2) conjugated with iron oxide nanoparticles, for the detection of nodal metastasis in HER2+ breast cancer patients. MSH2IA is currently being investigated in a first-in-human phase 1 study (ACTRN12621000126819) in HER2+ breast cancer patients who are diagnosed to have suspicious nodes by conventional imaging. Methods The key objectives of the phase 1 study are safety and tolerability of MSH2IA and confirmation that MSH2IA drains to the axillary lymph nodes. The study also explores MSH2IA’s ability to detect metastatic nodes when used with magnetic resonance imaging (MRI), with tumor status assessed by standard tissue histopathology. All eligible subjects receive a 22.5 mg (iron equivalent) subareolar or peritumoral injection of MSH2IA. MRI of the axilla are obtained before and 24 to 72 hours after MSH2IA injection. Core biopsy or dissection of a node suspicious by ultrasound is obtained for histopathology assessments. After completing the first cohort of 6 subjects, the protocol was amended to include the insertion of an MRI compatible clip in a node suspicious by ultrasound to localize the suspicious node for core biopsy and postdose MRI scan. Review of MRI scans and histopathology are performed in respective central laboratories. Results Thirteen participants with HER2+ breast cancer have completed the study. MSH2IA appears safe and well tolerated. The imaging agent, as administered, is detectable by MRI and pathology, confirming that MSH2IA drains to the lymph nodes via the chosen route of administration. In postdose MRI scans, study central radiologists reported distinct and differentiable MRI appearance in morphologically normal and suspicious nodes. The presence of a distinct postdose MR image appearance was confirmed by a group of independent radiologists in a separate blinded review. While normal nodes appeared with homogeneous hypointensity, morphologically suspicious nodes showed partial irregular darkening and/or speckled heterogeneous hypointensity. In evaluable subjects, histopathology of the core biopsies obtained from the clipped nodes confirmed the presence of HER2+ nodal metastasis, providing preliminary evidence for node-level concordance between MRI vs pathology observations. Safety, imaging, and pathology results from all available subjects will be presented. This phase 1 study in Australia will be closing enrollment by July 31, 2023. A phase 2 study in the United States and elsewhere is being planned with the objectives of optimizing dose, schedule, and imaging parameters for best diagnostic performance for clinical utility. Conclusion Available data from the ongoing phase 1 study show that MSH2IA appears safe and drains to the axillary lymph nodes. MSH2IA displays a distinct and differentiable MRI appearance in nodes morphologically highly suspicious for tumor, which is confirmed to be HER2+ metastasis by histopathology by node level concordance. This data provides preliminary proof of principle for the mechanism of molecularly targeted MR imaging and suggests that MSH2IA has the potential to provide tumor-specific MR imaging not currently available in conventional axillary imaging. Citation Format: Jane Fox, Shanta Velaiutham, Natalie Yang, Eddie lau, Kowsi Murugappan, Beena Kumar, Alex Laslowski, Koushik Govindarajan, Steven Reich, Stephen Thomas, Nitika Neha, Marie Zhang, Isaac Bright. MagSense® HER2, a Molecularly Targeted Magnetic Resonance Imaging Agent for the Detection of Axillary Nodal Metastasis in Subjects with Human Epidermal Growth Factor Receptor 2 Positive (HER2+) Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS05-03.

Abstract PO2-07-12: Analysis Of Malignity Rates Of Percutaneous Biopsy In Lymph Nodes Of Breast Cancer Patients

Abstract BACKGROUND: The evaluation of regional lymph nodes in patients with breast cancer is one of the main predictive and prognostic factors for treatment. The methods of percutaneous biopsies of suspicious lymph nodes frequently used are fine-needle aspiration cytology (FNA) and core needle biopsy (CORE). According to the international literature, CORE and FNA are considered diagnostic methods with high specificity (98% vs. 99%), however, the FNA may present up to 21% of inconclusive results by insufficient material. Although CORE is well established as a percutaneous method for diagnostic evaluation of suspected breast lesions, the literature is scarce on the use of this technique for the evaluation of suspicious lymph nodes in breast cancer patients. OBJECTIVE: Analyze the positivity of FNA and CORE performed in suspicious lymph nodes for breast cancer metastasis according to the anatomical location of biopsies and the type of needle used, verifying which technique was preferred. METHODS: A retrospective study was conducted by evaluating the database of patients treated in a public hospital in São Paulo, Brazil. Women submitted to ultrasound-guided percutaneous biopsy of lymph nodes from May 2015 to November 2019 were included in the study. The data were analyzed using IBM-SPSS version 27 and Microsoft EXCEL version 2010. RESULTS: A total of 499 biopsies were performed and the mean age of the women was 54.2 years (SD± 11.9) in the CORE group and 53.4 years (SD± 11.8) in the FNA group (p=0.619). According to the anatomical location, 385 were axillary (77.2%), 62 supraclavicular (12.4%), 48 cervical (9.6%) and 4 infraclavicular (0.8%). Regarding the type of needle, 393 were CORE (78.8%) and 106 were FNA (21.2%). When analyzing the results of the FNA, 38 (35.8%) did not present enough material, 31 (29.2%) were positive, 32 (30.2%) were negative and 5 (4.8%) showed atypical cells. Among the 393 CORE performed, 255 (64.9%) were positive, 132 (33.6%) were negative, 1 (0.3%) showed atypical cells and 5 (1.3%) had no representative material. No complications were reported after the procedures. CONCLUSION: CORE was the preferred diagnostic technique in our center, being considered a feasible procedure to evaluate lymph nodes in different sites and with low rates of inconclusive results by insufficient material. In the future, studies evaluating indirect costs may confirm the feasibility of CORE in patients with suspicious lymph nodes in terms of obtaining greater agility and resolutive conducts in the public healthcare system. Citation Format: Marina Diogenes, Andressa Amorim, ANDRE MATTAR, MARCELO ANTONINI, Luiz Henrique Gebrim, REGINALDO COELHO LOPES, Luciana Damous. Analysis Of Malignity Rates Of Percutaneous Biopsy In Lymph Nodes Of Breast Cancer Patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-07-12.

Abstract PO3-23-03: Radar reflectors for marking of target lymph nodes in patients receiving neoadjuvant chemotherapy for breast cancer – a subgroup analysis of the prospective AXSANA (EUBREAST-03) trial

Abstract Background: Surgical staging procedures of the axilla in breast cancer patients converting from a clinically positive (cN+) to a clinically negative (ycN0) lymph node status during neoadjuvant chemotherapy (NACT) vary across countries and within individual countries. The international prospective AXSANA (EUBREAST-03) study aims at comparatively evaluating long-term outcomes of different staging procedures such as axillary lymph node dissection (ALND), sentinel lymph node biopsy (SLNB), target lymph node biopsy (TLNB) and targeted axillary dissection (TAD). The comparison of marking techniques for the target lymph node (TLN) is a secondary endpoint. In this subgroup analysis, we report on the largest yet prospective cohort of patients receiving a radar reflector for marking of the TLN prior to NACT. Methods: The AXSANA study is an international prospective cohort study including cN+ patients converting to ycN0 status and treated with different axillary staging techniques according to the standard at their treating institution. The study was initiated by the EUBREAST network and started enrollment in August 2020. Eligible patients have cT1-4c tumors, initially present with axillary lymph node metastasis and receive neoadjuvant chemotherapy. Patients converting to ycN0 status are followed up for 5 years irrespectively of the ypN status. In the present subgroup analysis, only patients with a TLN marked by a radar reflector were included. We prospectively examined the retrieval rate of radar reflectors and the identification rate of the TLN (defined as unequivocal removal of the lymph node, i.e., the presence of lymphatic tissue in the TLN specimen and/or pathological confirmation of post-NACT changes typical for metastatic lymph nodes responding to treatment). Results: A TLN was marked using a radar reflector in 74 patients prior to NACT. The median age was 52 years (range: 32-77). The most common subtype was no special type in 68 (92%) patients and invasive lobular cancer in 7 (7%) patients. Most patients (n = 44, 59%) had one suspicious node at time of diagnosis, followed by two (n = 15, 20%), three (n = 10, 14%) or ≥ four suspicious nodes (n = 5, 5%). Only one TLN was marked in 73 (99%) patients and two nodes were marked in one patient (1%). Fifteen patients (20%) had a MRI between marker placement and surgery. In 4 out of 15 cases (27%), MRI artifacts were described. However, the assessment of MRI was limited due to artifacts only in one out of these four patients (25%). Out of the 74 patients with radar reflector marked TLN, 45 (61%) had undergone final surgery at the time of analysis and 29 (39%) are still under NACT. 36 out of 45 patients (80%) who received final surgery converted to ycN0. Most patients had undergone a TAD (n = 41, 91%), followed by TLNB in 7% (n = 3) and upfront ALND in 2% of cases (n = 1). All radar reflectors were successfully removed. In 44 out of 45 patients (98%) the TLN was unequivocally identified and removed. In one patient the tissue specimen containing radar reflector consisted of fat tissue and no lymphatic tissue was identifiable, so it remains unclear whether the TLN was excised, or the reflector might have dislocated. 29 patients (65%) had converted to ypN0 status. Conclusion: To the best of our knowledge this is the largest prospective series of patients receiving a radar reflector for the marking of TLN prior to NACT for breast cancer. The removal rate of the marker and the detection rate of the target node were very high. Our data demonstrate that radar reflectors are a reliable tool for marking of target lymph nodes before neoadjuvant treatment. Citation Format: Maggie Banys-Paluchowski, Steffi Hartmann, Jana de Boniface, Oreste Davide Gentilini, Timo Basali, Elmar Stickeler, Michael Untch, Franziska Ruf, Sarah Fröhlich, Marc Thill, Michael P. Lux, Florentia Peintinger, Guldeniz Karadeniz Cakmak, Isabel Rubio, Michalis Kontos, Rosa Di Micco, Dawid Murawa, Ellen Schlichting, Bilge Aktas Sezen, Achim Rody, Dagmar Langanke, Nana Bündgen, Jose Ignacio Sanchez-Mendez, Renu Buss-Steidle, Christine Mau, Nana Buchmann, Sabine Riemer, Marit Helene Hansen, Nina Ditsch, Thorsten Kühn. Radar reflectors for marking of target lymph nodes in patients receiving neoadjuvant chemotherapy for breast cancer – a subgroup analysis of the prospective AXSANA (EUBREAST-03) trial [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-23-03.

Abstract PO5-02-12: Comparison of survival outcomes according to axillary ultrasonography findings and cytology results in early-stage breast cancer patients

Abstract Purpose: Axillary lymph node dissection and sentinel lymph node biopsy are associated with increased risk of post-surgical complications including lymphedema and recent trials have raised questions about the therapeutic benefit of axillary operation in early-stage breast cancer patients. While treatment options for lymph nodes with negative findings on axillary ultrasonography (AUS) or positive findings on fine needle aspiration biopsy (FNAB) are evident, data regarding lymph nodes that are suspicious on AUS but negative by FNAB are limited. Thus, we aimed to compare clinicopathological characteristics of AUS positive and FNAB negative patients with those of AUS negative or FNAB positive patients. Materials and Methods: Medical records of patients who underwent breast cancer surgery between January 2010 and December 2017 were reviewed. Patients were grouped into the following three groups: (a) negative findings on AUS, (b) suspicious findings on AUS but negative on FNAB, (c) and FNAB positive. A total of 4,506 patients were included for analysis, with 3,771 patients with no suspicious lymph nodes on AUS, 557 patients who had suspicious AUS findings but were negative on FNAB, and 178 patients with positive findings on both AUS and FNAB. Primary endpoints were disease free survival (DFS) and recurrence free survival (RFS), and secondary endpoint was overall survival (OS). Results: At a median follow-up period of 92 months, DFS and RFS was significantly higher in the AUS negative group compared to the other two groups (10-year-DFS: 91.6% vs 87.5% vs 75.7%, 10-year-RFS: 95.0% vs 89.9% vs 77.1%, p &amp;lt; 0.001). In terms of OS, AUS negative group and the AUS positive and FNAB negative group did not show statistically significant survival difference (10-year-OS: 94.5% vs 92.8%, p = 0.061), while the FNAB positive group showed significantly lower survival rates (10-year-OS: 81.8%, p &amp;lt; 0.001). Multivariable analysis revealed that not AUS positive and FANB negative but positive FNAB was significantly associated with poor RFS. Moreover, hormone receptor (HR) positive and HER2 negative subtype showed poor DFS and RFS in subgroup analysis. Conclusion: Early breast cancer patients with suspicious findings on AUS but negative FNAB results had similar OS but inferior DFS and RFS compared to those with negative features on AUS, especially in HR(+)HER2(-) subtype. While further prospective trials are warranted to determine whether additional treatment is necessary, close surveillance is recommended for this subgroup of patients. Figure1. Overall survial and Disease free survival according to axillay US and FNAB status Table1. patients' characteristics Table2. prognostic factors for overall survival and disease free survival related to axillary US and FNAB status Citation Format: Suk Jun Lee. Comparison of survival outcomes according to axillary ultrasonography findings and cytology results in early-stage breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-02-12.

Abstract PO3-03-03: Prospective non-randomized study to compare accuracy of clinical examination under anesthesia, axillary ultrasound and histo-pathological evaluation for axillary nodal staging in women with clinically N0 early breast cancer

Abstract Introduction: Accurate assessment of axillary lymph nodes is crucial in the management of early breast cancer (EBC), especially in clinically node negative (cN0) axilla to avoid extensive axillary surgery. Clinical examination alone underestimates nodal disease in nearly 30% women with cN0 axilla. The current study compares, in cN0 axilla, the benefit of axillary ultrasonography (USG) and clinical axillary examination under anesthesia (EUA) to predict involvement of axillary lymph nodes. The gold standard in these patients however remains pathological evaluation after sentinel node biopsy/low axillary sampling (SNB/LAS) and a complete axillary lymph node dissection (ALND) if node positive. Methodology: Prospectively, 500 women with cN0 EBC were enrolled from Aug 2015 to April 2023 in a study approved by Institutional Ethics Committee. After informed consenting, a preoperative axillary USG was carried out in addition to standard breast imaging to determine number of axillary node(s) and its architecture. The USG assessment was labeled as suspicious or not and the result was blinded to the surgeons. A USG-guided FNAC was not performed as it would then be difficult to blind the surgeon and pathologist preoperatively. During surgery, an initial axillary EUA was performed before starting and any suspicious node was documented. This was followed by axillary staging by standard dual tracer SNB/LAS. A complete axillary dissection was done (level 1-3) if any node was positive on frozen section evaluation or final histopathology. Axillary node histopathology was the gold standard for comparison of effectiveness of clinical exam, USG, EUA, and SNB/LAS for prediction of axilla. Standard diagnostic tests such as sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were used. Results: Thirty-six patients were excluded in the final analysis (disease progression, chemotherapy first, or had a surgery elsewhere). Of the eligible 464 cN0 patients, 129 were detected to have axillary metastases (27.8%) in final histopathology. The 2 interventions namely USG axilla, EUA were compared to final axillary nodal histopathology. Axillary USG reported suspicious/indeterminate node(s) in 129 (27.8%) patients. USG had a low sensitivity of 46.5% and a low PPV of 46.5% to identify a positive node. However, the specificity and NPV both were 79.4%. Axillary USG was 70.2% accurate in predicting axillary nodal involvement. EUA also had sensitivity of 60% and low PPV of 14.8%. However, the specificity of EUA was 73.4%, NPV of 95.9%; higher than that of USG. EUA was 72.4% accurate. SNB/LAS had the sensitivity of 93.3%, specificity 79.2%, NPV 82.9%, PPV 91.6% and accuracy rate 89.2% in predicting a positive axilla. Conclusions: While the fallacy of clinical exam remains at 27.8%, both USG alone (without FNAC) and EUA failed in predicting a positive axillary node. EUA fared better at predicting a negative axilla. USG guided FNAC would perhaps improve the sensitivity of USG, however additional investigations are difficult in resource constraint and high-volume center, especially, when surgical interventions like SNB or LAS remain standard of care. Table 1 Citation Format: Vani Parmar, Zeal Sanghvi, Shalaka Joshi, Nita Nair, Palak Popat, Seema Kembhavi, Souwmyashree KN, Soujanya Mynalli, Purvi Thakkar, Garvit Chitkara, Sangeeta Desai, Tanuja Shet, Rajendra Badwe. Prospective non-randomized study to compare accuracy of clinical examination under anesthesia, axillary ultrasound and histo-pathological evaluation for axillary nodal staging in women with clinically N0 early breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-03-03.

Abstract PO4-19-04: AXSANA – EUBREAST-3: An international prospective multicenter cohort study to evaluate different surgical methods of axillary staging in clinically node-positive breast cancer patients treated with neoadjuvant chemotherapy

Abstract Background The optimal surgical staging procedure of the axilla in patients who convert from a clinically positive (cN+) to a clinically negative node status (ycN0) through neoadjuvant chemotherapy is still controversial. Widely diverse techniques such as full Axillary Lymph Node Dissection (ALND), Targeted Axillary Dissection (TAD), Targeted Lymph Node Biopsy (TLNB) and Sentinel Lymph Node Biopsy (SLNB) alone are given preference in different international guidelines. So far, no comparative data on the oncological outcome or the morbidity of the different procedures are available. Further research is needed to safely de-escalate the extent of axillary surgery in this patient group. Trial design The AXSANA study is an international prospective cohort study including cN+ patients converting to ycN0 status and treated with different axillary staging techniques according to the standard at their treating institution. The study was initiated by the EUBREAST network. The trial includes patients with cT1-4c tumors, who present initially with axillary lymph node metastasis scheduled for neoadjuvant chemotherapy. According to an amendment in 2020 the inclusion of patients with highly suspicious nodes without confirmation using a minimally invasive biopsy is allowed. All patients converting to ycN0 status undergo follow-up for 5 years irrespectively of the ypN status. Primary endpoints: Invasive disease-free survival, axillary recurrence rate and health-related quality of life (HRQoL). HRQoL are evaluated using four standardized questionnaires (EORTC QLQ-C 30, EORTC QLQ-BR 23, Lymph ICF and SOC-13) at baseline and after 1, 3 and 5 years after surgery. Secondary endpoints are the feasibility and performance of different axillary staging techniques (detection rate, number of removed lymph nodes and association with complications, arm morbidity and quality of life, operating time and use of clinical and economic resources); impact of learning curve, and the detailed mapping of surgical and oncological treatment standards in different countries. The impact on different regional treatment strategies (radiotherapy, ALND) in patients with ypN0(i+), ypN1(mi) and ypN1 is assessed. Current status of the study: 4336 patients from 284 study sites and 26 countries were enrolled in the study between June 2020 and June 2023. Among 3722 patients with a defined surgical concept 1631 women were scheduled for TAD, 1483 for ALND, 469 for SLNB, 25 for TLNB and 109 for other procedures. A target lymph node was marked in 2309 patients, most frequently using clips/coils (1850, 80.1%), followed by magnetic seeds (219, 9.5%), carbon ink (171, 7.4%), radar marker (80, 3.5%), radioactive seeds (4, 0.2%) and other techniques (24, 1.0%). Funding: AGO-B, GBG, Claudia-von Schilling Foundation, Ehmann Foundation, Eugen und Irmgard Hahn Foundation, AWOgyn, Merit Medical, Endomagnetics, Mammotome Contact information: Prof. Dr. Thorsten Kühn Department of Gynecology and Obstetrics University of Ulm, Germany Baumreute 37 D-73730 Esslingen Germany E-Mail: kuehn.thorsten@t-online.de Citation Format: Thorsten Kühn, Steffi Hartmann, Elmar Stickeler, Jana de Boniface, Oreste Davide Gentilini, Sarah Fröhlich, Franziska Ruf, Marc Thill, Michael Hauptmann, Guldeniz Karadeniz Cakmak, Isabel Rubio, Maria Luisa Gasparri, Michalis Kontos, Eduard-Alexandru Bonci, Laura Niinikoski, Bilge Aktas Sezen, Rosa Di Micco, Dawid Murawa, Geeta Kadayaprath, David Pinto, Florentia Peintinger, Matilda Appelgren, Janine M. Simons, Marjolein Smidt, Ellen Schlichting, Lukas Dostalek, Elisabeth Thiemann, Markus Hahn, Michael Schrauder, Semra Gunay, Gunay Gurleyik, Nina Helidon, Hagigat Valiyeva, Ashutosh Kothari, Marian Vanhoeij, Andraz Perhavec, Tsvetomir Ivanov, Dov Zippel, Lia Rebaza, Sarun Thongvitokomarn, Sibylle Loibl, Maggie Banys-Paluchowski. AXSANA – EUBREAST-3: An international prospective multicenter cohort study to evaluate different surgical methods of axillary staging in clinically node-positive breast cancer patients treated with neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-19-04.

Abstract PO3-23-07: Evaluation of the role of axillary ultrasound to estimate axillary nodal burden to guide de-escalation of upfront axillary surgery in node positive early breast cancer patients

Abstract Background: Axillary surgery is now routinely de-escalated in clinically node negative breast cancer patients with limited axillary nodal burden (up to 2 involved sentinel nodes) based on the results of ACOSOG-Z0011 and AMAROS trials. However, patients with proven axillary metastasis following on ultrasound (AUS) guided core needle biopsy (CNB), undergoing primary surgery are still subjected to an axillary lymph node dissection (ALND) irrespective of the magnitude of the axillary nodal burden. If we could predict axillary nodal burden with a low false negative rate (FNR) for the presence of extensive axillary nodal involvement, we can then hypothesize that axillary surgery could be safely de-escalated in this cohort of patients. We investigated whether pre-operative AUS suggesting limited axillary burden is sensitive enough to rule out gross axillary disease burden. Methods: A single institution retrospective study. We undertook an electronic chart review of all T1 to T3 patients undergoing upfront ALND with either mastectomy or breast conserving surgery between January 2019 and June 2023. Patients with palpable axillary nodes, locally advanced breast cancer or a completion ALND after positive sentinel lymph node biopsy (SLNB) were excluded from the study. Clinical and pathological characteristics associated with nodal burden of disease were evaluated. Limited axillary burden was defined as &amp;lt; 2 involved nodes with ≥3 taken as gross nodal burden for primary analyses. Sensitivity analyses were carried out with limited axillary burden defined as &amp;lt; 3 involved nodes (N1) and ≥4 (N2) taken as gross nodal burden. Subgroup analyses in T1 or T2 tumors were carried out as well. The probabilities of discordant events, defined as limited burden on AUS-CNB but gross burden on final histopathology evaluation (HPE), assuming 10% FNR, were estimated using inverse cumulative binomial distribution function. Results: Data on the exact number of suspicious nodes on AUS were missing for 2 patients, therefore, the final study cohort included 39 patients. The correlation between AUS nodal burden and that on HPE was moderate (Spearman’s rho = 0.48; p = 0.0018). The sensitivity and specificity of AUS in identifying gross nodal burden were 61% and 81% respectively. Observation of 9 discordant events in 22 patients with low burden on AUS ruled out an FNR of &amp;lt; 10% with 99.99% certainty. The sensitivity and specificity in T1/T2 subgroup were 60% and 75% respectively. The sensitivity analyses classifying N1 as limited and N2 as gross axillary burden showed the sensitivity and specificity of 35% and 82% respectively and an FNR of &amp;lt; 10% was ruled out with 99.996% certainty. Conclusion: Pre-operative AUS alone lacks the sensitivity and specificity to accurately predict the true axillary nodal burden to safely guide de-escalation of axillary surgery. AUS followed by targeted axillary dissection (TAD) in conjunction with a dual technique SLNB may provide the desired sensitivity and specificity to guide de-escalation of axillary surgery. A prospective evaluation of this approach is merited. Given the limited number of patients that could be enrolled in such prospective study from individual institutions, an international collaborative effort is needed to address this important research question. Citation Format: Nidhi Garg, Mangesh Thorat, Hisham Hamed, Ashutosh Kothari. Evaluation of the role of axillary ultrasound to estimate axillary nodal burden to guide de-escalation of upfront axillary surgery in node positive early breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-23-07.