Node-negative Breast Cancer Research Articles

ASO Author Reflections: De-escalating Axillary Surgery in Patients with Clinically Node-Negative Breast Cancer After Neoadjuvant Chemotherapy.

ASO Author Reflections: De-escalating Axillary Surgery in Patients with Clinically Node-Negative Breast Cancer After Neoadjuvant Chemotherapy.

079. The Diagnostic Duel: Single Immunohistochemistry vs. in Combination with Hematoxylin Eosin in Sentinel Lymph Node Biopsy for Breast Cancer—Insights from a Meta-Analysis

Background: The timing of sentinel lymph node biopsy (SLNB) has gained significance with the increased use of neoadjuvant chemotherapy (NAC) in breast cancer. Hematoxylin and eosin (H&E) is the standard histological stain, yet the optimal histopathological protocol for SLNB remains unclear. The role of immunohistochemistry (IHC) in enhancing diagnostic accuracy is still debated. This study evaluates the false-negative rate (FNR) of SLNB in clinically node-negative breast cancer patients after NAC, comparing IHC alone versus IHC combined with H&E staining through a systematic review and meta-analysis. Methods: We conducted a comprehensive search of PubMed, Embase, and the Cochrane Library from January 2002 to August 2024, focusing on patients undergoing SLNB after NAC followed by axillary lymph node dissection (ALND). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model via Review Manager Software version 5.3. Results: A total of 1,456 patients across 16 studies were analyzed. The FNRs varied from 0% to 33%. The estimated FNR was 1.55 (95% CI: 0.71-3.38) for studies using IHC, while the pooled FNR for H&E alone was 11% (95% CI: 4%-18%) compared to 4% (95% CI: 1%-7%) for H&E with IHC. No significant difference in FNR was observed between the two staining methods (P = 0.28). Conclusion: IHC combined with H&E is technically feasible and offers comparable accuracy for axillary staging in initially clinically node-negative breast cancer patients post-NAC.

Benefit of systemic therapy in MINDACT patients with small, ER-positive, HER2-negative breast cancers

Small, hormone receptor-positive (HR+), HER2-negative (HER2-), lymph node-negative breast cancers are associated with relatively low rates of disease recurrence and have therefore been underrepresented in clinical trials assessing the effects of systemic therapy. Consequently, it remains uncertain if this patient population derives benefit from these treatments. For this exploratory analysis, we selected MINDACT (NCT00433589) patients with a HR+, HER2-, T1ab (≤1 cm) tumor and negative lymph nodes. Patients with discordant clinical risk and MammaPrint genomic risk classification were randmomized to receive chemotherapy based on either the clinical or the genomic risk assessment. Endocrine therapy treatment was based on local guidelines. 715/6693 (10.7%) MINDACT patients had HR+, HER2-, T1abN0 breast cancer and were included in this analysis. All were clinically low-risk, 124/715 (17.3%) were genomic high-risk. For genomic high-risk tumors, 8-year distant metastasis-free survival (DMFS) was 92.9% (95% CI 86.2–96.4%) compared to 95.0% (95% CI 92.8–96.6%) for genomic low-risk tumors. For genomic high-risk tumors treated with or without chemotherapy, 8-year DMFS was 89.2% (95% CI 73.6–95.8%) and 94.1% (95% CI 82.9–98.1%), respectively. For genomic low-risk tumors, the 8-year DMFS and disease-free survival (DFS) were 96.1% (95% CI 93.4–97.6%) and 89.3% (95% CI 85.5–92.2%) when treated with endocrine therapy and 92.9% (95% CI 87.9–95.9%) and 79.4% (95% CI 72.5–84.8%) without. In conclusion, although the number of randomized patients is small, patients with small, genomic high-risk breast cancer did not seem to derive benefit from chemotherapy. Endocrine therapy was associated with improved outcomes even in genomic low-risk breast cancers.

Significance of Residual Nodal Disease in Clinically Node-Negative Breast Cancer After Neoadjuvant Chemotherapy.

Trials evaluating omission of axillary dissection (ALND) in patients with cN0 breast cancer with positive sentinel lymph nodes (SLNs) haveexcluded neoadjuvant chemotherapy (NACT). It remains unclear whether the data can be extrapolated to cN0 patients undergoing NACT. This study sought to identify factors associated with positive SLNs and additional disease on ALND in cT1-2N0 disease after NACT. The authors queried their database for cT1-2N0 patients treated with NACT followed by SLN biopsy from 1996 to 2022. Physical examination and ultrasound determined clinical nodal status. Multivariable logistic regression identified factors associated with positive SLNs and disease on ALND. Of 1930 patients, 234 (12.1%) had positive SLNs. Positive SLNs were predicted by hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) status (odds ratio [OR] 2.5; p < 0.0001), lobular histology (OR 1.8; p = 0.007), multifocality (OR 2; p = 0.001), grade 1 tumors (OR 2.5; p = 0.002), and cT2 category (OR 1.9; p = 0.004). Of the 234 patients with positive SLNs and known SLN metastasis size, 148 (63.2%) underwent ALND, and 39 (26.4%) had additional positive nodes. Increasing patient age predicted disease on ALND (OR 1.03; p = 0.02). No additional positive nodes on ALND were identified in patients with only isolated tumor cells compared with 12.3% who had micrometastases and 37.6% who had macrometastases (p = 0.01). During a 5-year median follow-up period of the SLN-positive patients, three (1.3%) experienced axillary recurrence and twoof the three underwent ALND at the initial surgerywith no additional positive nodes. In cT1-2N0 breast cancer, HR+/HER2- status, lobular histology, multifocality and cT2 category predicted positive SLNs after NACT. Older age predicted positive nodes on ALND. Patients with positive SLNs had low axillary recurrence rates. These findings support investigation into omission of ALND in cN0 breast cancer and a low volume of SLN disease after NACT.

Nodal involvement in patients with small, clinically node-negative HER2-positive breast cancer after staging with FDG-PET/CT and neoadjuvant systemic therapy

BackgroundGuidelines recommend systemic therapy for stage I HER2+ breast cancer (BC). Neoadjuvant systemic treatment (NAST) allows response-guided adjuvant treatment. However, prior to NAST only clinical nodal staging is available, risking undertreatment if ypN+ is observed. Here, we aim to evaluate the impact of FDG-PET/CT and NAST on nodal disease status in patients with small, node-negative HER2+ BC. MethodsThis retrospective study included patients with small (≤3 cm), clinically node-negative HER2+ BC diagnosed between 2011 and 2023. Primary outcome was the proportion of patients with nodal disease on final pathology after upfront surgery or NAST followed by surgery with or without FDG-PET/CT. Patients received either paclitaxel + trastuzumab (PT) or a more extensive regimen. ResultsOf the 370 included patients, 183 underwent FDG-PET/CT, detecting regional or distant metastases in 14 patients (7.7 %).Among 356 patients with cN0 disease, 44.1 % (n = 157/356) had upfront surgery, with only 3 % (5/157) having an FDG-PET/CT. The remaining 55.9 % (199/356) started with NAST, with 82 % (n = 164/199) having an FDG-PET/CT. Among patients treated with NAST, 36 % received PT.Nodal involvement on pathology was seen in 19.1 % (n = 29/152) after upfront surgery without FDG-PET/CT and 6.1 % (10/164) after NAST combined with FDG-PET/CT.After NAST, 58 % had a pCR (PT: 49 %, other: 63 %). Nodal involvement on final pathology was seen in 6.9 % after PT and in 5.5 % after more extensive regimen. ConclusionsThe proportion of patients with ypN + after NAST combined with FDG-PET/CT was only 6.1 %. Neoadjuvant treatment can be a safe treatment strategy for patients with stage I HER2+ BC.

Predictive value of methylene blue combined with indocyanine green in sentinel lymph node metastasis in breast cancer: a prospective pilot cohort study.

The status of sentinel lymph nodes is crucial for prognosis and treatment decisions in breast cancer patients. This study aimed to evaluate the predictive value of combined methylene blue and indocyanine green for sentinel lymph node metastasis in breast cancer. This prospective cohort study enrolled 90 clinically node-negative breast cancer patients. Methylene blue and indocyanine green were injected locally before surgery. Sentinel lymph nodes were grouped based on fluorescence intensity and methylene blue staining. A binary logistic regression model was established using 285 lymph node groups to predict metastatic risk. A total of 475 lymph nodes were identified, with 33 being metastatic. The metastatic risk reached 70% for partially blue-stained and weakly fluorescent lymph nodes between 1-2 cm. The model revealed associations between lymph node size, dye staining patterns, and metastatic risks (P<0.05). The AUC of the ROC curve was 0.855. The staining pattern of combined methylene blue and indocyanine green could predict risks of sentinel lymph node metastasis and facilitate rapid intraoperative identification of high-risk lymph nodes.

Differences in axillary ultrasound protocols among prospective de-escalating axillary surgical staging trials in clinically node negative early breast cancer patients

BackgroundSurgical axillary staging of the axilla is a topic of debate regarding the potential of de-escalation in clinically node negative (cN0) early breast cancer patients treated with breast-conserving therapy. Axillary ultrasound is important to determine clinical nodal status. The aim of the current narrative review is to provide an overview of prospective trials on de-escalating axillary surgical staging in cN0 early breast cancer patients, with an emphasis on axillary ultrasound protocols. MethodsThis narrative review provides an overview of the prospective de-escalating axillary surgical staging trials, in terms of comparing sentinel lymph node biopsy (SLNB) versus complete omission of SLNB, in cT1/2N0 patients treated with breast-conserving therapy. Information from each trial was collected, including reported axillary ultrasound protocols (including cortical thickness cut-off value) and axillary ultrasound-guided biopsy technique (fine-needle aspiration or core-needle biopsy). ResultsThere is one recently published prospective trial and three ongoing prospective trials within the topic of this narrative review. Number of included patients in these trials ranges from 1405 to 5505 patients. The included trials differed whether or not to include patients with suspicious axillary ultrasound findings and a negative ultrasound-guided biopsy. Cortical thickness cut-off value ranged from 2.3 mm to 3.0 mm. Different ultrasound-guided biopsy techniques were performed among the included trials. ConclusionProspective de-escalating axillary surgical staging trials in clinically node negative early breast cancer patients treated with breast-conserving therapy do report differences in terms of axillary ultrasound protocols and ultrasound-guided biopsy techniques. Axillary ultrasound protocols do require uniformity in order to improve extrapolation of these trial results.

Prediction of High Nodal Burden in Patients With Sentinel Node–Positive Luminal ERBB2-Negative Breast Cancer

In patients with clinically node-negative (cN0) breast cancer and 1 or 2 sentinel lymph node (SLN) macrometastases, omitting completion axillary lymph node dissection (CALND) is standard. High nodal burden (≥4 axillary nodal metastases) is an indication for intensified treatment in luminal breast cancer; hence, abstaining from CALND may result in undertreatment. To develop a prediction model for high nodal burden in luminal ERBB2-negative breast cancer (all histologic types and lobular breast cancer separately) without CALND. The prospective Sentinel Node Biopsy in Breast Cancer: Omission of Axillary Clearance After Macrometastases (SENOMAC) trial randomized patients 1:1 to CALND or its omission from January 2015 to December 2021 among adult patients with cN0 T1-T3 breast cancer and 1 or 2 SLN macrometastases across 5 European countries. The cohort was randomly split into training (80%) and test (20%) sets, with equal proportions of high nodal burden. Prediction models were developed by multivariable logistic regression in the complete luminal ERBB2-negative cohort and a lobular breast cancer subgroup. Nomograms were constructed. The present diagnostic/prognostic study presents the results of a prespecified secondary analysis of the SENOMAC trial. Herein, only patients with luminal ERBB2-negative tumors assigned to CALND were selected. Data analysis for this article took place from June 2023 to April 2024. Predictors of high nodal burden. High nodal burden was defined as ≥4 axillary nodal metastases. The luminal prediction model was evaluated regarding discrimination and calibration. Of 1010 patients (median [range] age, 61 [34-90] years; 1006 [99.6%] female and 4 [0.4%] male), 138 (13.7%) had a high nodal burden and 212 (21.0%) had lobular breast cancer. The model in the training set (n = 804) included number of SLN macrometastases, presence of SLN micrometastases, SLN ratio, presence of SLN extracapsular extension, and tumor size (not included in lobular subgroup). Upon validation in the test set (n = 201), the area under the receiver operating characteristic curve (AUC) was 0.74 (95% CI, 0.62-0.85) and the calibration was satisfactory. At a sensitivity threshold of ≥80%, all but 5 low-risk patients were correctly classified corresponding to a negative predictive value of 94%. The prediction model for the lobular subgroup reached an AUC of 0.74 (95% CI, 0.66-0.83). The predictive models and nomograms may facilitate systemic treatment decisions without exposing patients to the risk of arm morbidity due to CALND. External validation is needed. ClinicalTrials.gov Identifier: NCT02240472.

Results of a Prospective Randomized Multicenter Study Comparing Indocyanine Green (ICG) Fluorescence Combined with a Standard Tracer Versus ICG Alone for Sentinel Lymph Node Biopsy in Early Breast Cancer: The INFLUENCE Trial

BackgroundFor clinically node-negative early breast cancer patients, sentinel lymph node biopsy (SLNB) using dual localization with blue dye and radioisotope (RI) is currently standard of care. Documented disadvantages with these tracers have prompted exploration of alternative agents such as fluorescent indocyanine green (ICG), which demonstrates high detection rates combined with other tracers. Results of a randomized study evaluating ICG as a single tracer for SLN identification are presented.MethodsOverall, 100 patients with unilateral, clinically node-negative, biopsy-proven invasive breast cancer (≤5 cm) scheduled for SLNB were recruited in two separate randomized cohorts, with 50 patients receiving ICG alone. Cohort 1 received ICG alone (n = 25) or combined with RI [Technetium99] (n = 25), while Cohort 2 received ICG alone (n = 25) or combined with blue dye (n = 25). The primary outcome was sensitivity for SLN identification.ResultsAmong evaluable patients (n = 97), the overall SLN identification rate was 96.9% (ICG alone = 97.9%; ICG + RI = 100%; ICG + blue dye = 92%). Node positivity rates were 14.9% for ICG alone, 16% for ICG combined with RI, and 20% for ICG combined with blue dye. There were no significant differences (p < 0.05) in performance parameters, with ICG alone being non-inferior to tracer combinations for procedural node positivity rates when adjusted for specific factors.ConclusionThese results support potential use of ICG as a sole tracer agent for routine SLNB, thereby avoiding disadvantages of RI and/or blue dye. The latter can be safely withheld as a co-tracer without compromising detection of positive nodes in primary surgical patients.

Omission of sentinel lymph node biopsy in patients with clinically axillary lymph node-negative early breast cancer (OMSLNB): protocol for a prospective, non-inferiority, single-arm, phase II clinical trial in China

IntroductionSentinel lymph node biopsy (SLNB) is a standard procedure for patients with clinically assessed negative axillary lymph nodes (cN0) during early-stage breast cancer (EBC). However, the majority of EBC patients...

GATA3 and markers of epithelial-mesenchymal transition predict long-term benefit from tamoxifen in ER-positive breast cancer

GATA binding protein 3 (GATA3) is essential for normal development of the mammary gland and associated with ER-positive breast cancer. Loss of GATA3 has been associated with epithelial-mesenchymal transition (EMT) in experimental studies. We investigated tumoral GATA3 in a cohort of postmenopausal patients with lymph-node negative breast cancer, randomized to adjuvant tamoxifen or control. Nuclear GATA3 expression was assessed with immunohistochemistry and GATA3 gene expression with Agilent microarrays. High GATA3 nuclear expression was associated with a lower rate of distant recurrence in ER-positive breast cancer (HR = 0.60, 95% CI 0.39–0.93). Low gene expression of GATA3 was associated with limited long-term benefit from adjuvant tamoxifen (interaction: p = 0.033). GATA3 gene expression was associated with the epithelial markers CDH1 (E-cadherin) and FOXA1, whereas negatively associated with several mesenchymal markers. Low expression of CDH1 was associated with marginal tamoxifen benefit (HR = 0.80 (0.43–1.49)), whereas patients with higher expression showed a significant benefit (HR = 0.33 (0.20–0.55), interaction: p = 0.029). In ER-positive breast cancer, diminished expression of GATA3 is associated with markers of EMT and poor long-term benefit from tamoxifen.

Completion axillary lymph node dissection for the identification of pN2–3 status as an indication for adjuvant CDK4/6 inhibitor treatment: a post-hoc analysis of the randomised, phase 3 SENOMAC trial

In luminal breast cancer, adjuvant CDK4/6 inhibitors (eg, abemaciclib) improve invasive disease-free survival. In patients with T1-2, grade 1-2 tumours, and one or two sentinel lymph node metastases, completion axillary lymph node dissection (cALND) is the only prognostic tool available that can reveal four or more nodal metastases (pN2-3), which is the only indication for adjuvant abemaciclib in this setting. However, this technique can lead to substantial arm morbidity in patients. We aimed to pragmatically describe the potential benefit and harm of this strategy on the individual patient level in patients from the ongoing SENOMAC trial. In the randomised, phase 3, SENOMAC trial, patients aged 18 years or older, of any performance status, with clinically node-negative T1-T3 breast cancer and one or two sentinel node macrometastases from 67 sites in five European countries (Denmark, Germany, Greece, Italy, and Sweden) were randomly assigned (1:1), via permutated block randomisation (random block size of 2 and 4) stratified by country, to either cALND or its omission (ie, they had a sentinel lymph node biopsy only). The primary outcome is overall survival, which is yet to be reported. In this post-hoc analysis, patients from the SENOMAC per-protocol population, with luminal oestrogen-receptor positive, HER2-negative, T1-2, histological grade 1-2 breast cancer, with tumour size of 5 cm or smaller were selected to match the characteristics of cohort 1 of the monarchE trial who would only have an indication for adjuvant abemaciclib if found to have 4 or more nodal metastases. The primary study objective was to determine the number of patients who developed patient-reported severe or very severe impairment of physical arm function after cALND (as measured by the Lymphedema Functioning, Disability, and Health [Lymph-ICF] Questionnaire) 1 year after surgery to avoid one invasive disease-free survival event at 5 years with 2 years of adjuvant abemaciclib, using invasive disease-free survival event data from cohort 1 of the monarchE trial. The SENOMAC trial is registered with ClincialTrials.gov, NCT02240472, and is closed to accrual and ongoing. Between Jan 31, 2015, and Dec 31, 2021, 2766 patients were enrolled in SENOMAC and randomly assigned to cALND (n=1384) or sentinel node biopsy only (n=1382), of whom 2540 were included in the per-protocol population. 1705 (67%) of 2540 patients met this post-hoc study's eligibility criteria, of whom 802 (47%) had a cALND and 903 (53%) had a sentinel lymph node biopsy only. Median age at randomisation was 62 years (IQR 52-71), 1699 (>99%) of 1705 patients were female, and six (<1%) were male. Among 1342 patients who responded to questionnaires, after a median follow-up of 45·2 months (IQR 25·6-59·8; data cutoff Nov 17, 2023), patient-reported severe or very severe impairment of physical arm function was reported in 84 (13%) of 634 patients who had cALND versus 30 (4%) of 708 who had sentinel lymph node biopsy only (χ2 test p<0·0001). To avoid one invasive disease-free survival event at 5 years with adjuvant abemaciclib, cALND would need to be performed in 104 patients, and would result in nine patients having severe or very severe impairment of physical arm function 1 year after surgery. As a method to potentially identify an indication for abemaciclib, and subsequently avoid invasive disease-free survival events at 5 years with 2 years of adjuvant abemaciclib, cALND carries a substantial risk of severe or very severe arm morbidity and so cALND should be discouraged for this purpose. Swedish Research Council, the Swedish Cancer Society, the Nordic Cancer Union, and the Swedish Breast Cancer Association.

Long-Term Outcomes of Adjuvant Trastuzumab for 9 Weeks or 1 Year for ERBB2-Positive Breast Cancer

The standard adjuvant treatment for patients with ERRB2-positive breast cancer is chemotherapy plus 1 year of trastuzumab. Shorter durations of trastuzumab administration improve cardiac safety, but more information is needed about their effect on survival. To compare survival outcomes after 9-week vs 1-year administration of trastuzumab with the same adjuvant chemotherapy. This post hoc secondary analysis of an open-label, multicenter, noninferiority-design randomized clinical trial included women aged 18 years or older with early ERBB2-positive, axillary node-negative or axillary node-positive breast cancer who were enrolled from January 3, 2008, to December 16, 2014, at 65 centers in 7 European countries. The current exploratory analysis was conducted after achieving the maximum attainable follow-up data when the last patient enrolled had completed the last scheduled visit in December 2022. Chemotherapy consisted of 3 cycles of docetaxel administered at 3-week intervals followed by 3 cycles of fluorouracil, epirubicin, and cyclophosphamide at 3-week intervals. Trastuzumab was administered in both groups for 9 weeks concomitantly with docetaxel. In the 9-week group, no further trastuzumab was administered after chemotherapy, whereas in the 1-year group, trastuzumab was continued after chemotherapy to complete 1 year of administration. The primary objective was disease-free survival (DFS). Distant DFS and OS were secondary objectives. Survival between groups was compared using the Kaplan-Meier method and log-rank test or univariable Cox proportional hazards regression. Among the 2174 women analyzed, median age was 56 years (IQR, 48-64 years). The median follow-up time was 8.1 years (IQR, 8.0-8.9 years); 357 DFS events and 176 deaths occurred. Trastuzumab for 9 weeks was associated with shorter DFS compared with trastuzumab for 1 year (hazard ratio [HR], 1.36; 90% CI, 1.14-1.62); 10-year DFS was 80.3% in the 1-year group vs 78.6% in the 9-week group. The 5-year and 10-year OS rates were comparable between the 9-week and 1-year groups (95.0% vs 95.9% and 89.1% vs 88.2%, respectively; HR for all time points, 1.20; 90% CI, 0.94-1.54). In multivariable analyses, 9-week treatment was associated with shorter DFS compared with 1-year treatment (HR for recurrence or death, 1.36; 95% CI, 1.10-1.68; P = .005), but there was no between-group difference in OS (HR, 1.22; 95% CI, 0.90-1.64; P = .20). Only 4 patients (0.2%) died of a cardiac cause. In this secondary analysis of a randomized clinical trial, 1-year vs 9-week adjuvant trastuzumab was associated with improved DFS among patients with ERRB2-positive breast cancer receiving chemotherapy, but there was no significant difference in OS between the groups. ClinicalTrials.gov Identifier: NCT00593697.

Intraoperative Nodal Palpation is a Mandatory Component of Sentinel Lymph Node Biopsy for Breast Cancer

Background: In the era of Z-0011, it is mandatory to decrease not only the false negative rate (FNR) of sentinel lymph node (SLN) biopsy but also the risk of residual metastatic nodes after SLN biopsy. Method: SLN biopsy with intraoperative nodal palpation (INP) was performed in patients with clinically node-negative (cN0) breast cancer. All identified blue and hot nodes were removed as blue/hot SLNs, and any suspicious palpable nodes were removed as palpable SLNs. Nodes that were incidentally removed with neighboring the blue/hot SLNs were classified as para-SLNs. Patients with positive SLNs on frozen section underwent axillary lymph node dissection (ALND) except for patients who met the Z-0011 and AMAROS criteria for exemption. Results: Palpable SLNs and para-SLNs were identified in 202 patients. Of 200 patients, excluding 2 patients only with palpable SLNs, 46 patients had involvements of blue/hot SLNs, and 14 had palpable and para-SLNs harboring additional metastasis. When false negative rate (FNR) was calculated based on blue/hot SLNs and palpable SLNs, the additional use of INP resulted in a FNR of 45.2%. Subsequently, ALND was performed in 43 patients with positive blue/hot or palpable SLNs. Residual nodal involvement was found in 28 (65%) of 43 patients after removing blue/hot SLNs. However, after removing palpable SLNs, the rate of residual nodal metastases significantly decreased from 65% (28/43) to 36% (13/36) (p=0.0133). Conclusion: INP decreased both the FNR of SLN biopsy and the risk of residual metastatic nodes after SLN biopsy.

Clinical and Genomic Risk for Late Breast Cancer Recurrence and Survival

BackgroundThe 21-gene recurrence score (RS) assay (Oncotype DX) is used to guide adjuvant chemotherapy use for patients with hormone receptor–positive, HER2 (human epidermal growth factor receptor 2)-negative, axillary node-negative breast cancer. Its role, however, in providing prognostic information for late distant recurrence when added to clinicopathologic prognostic factors is unknown.MethodsA patient-specific meta-analysis including 10,004 women enrolled in three trials was updated using extended follow-up data from TAILORx, integrating the RS with histologic grade, tumor size, and age at surgery for the RSClin tool. Cox models integrating clinicopathologic factors and the RS were compared by using likelihood ratio (LR) tests. External validation of prognosis for distant recurrence in years 0 to 10 and 5 to 10 was performed in an independent cohort of 1098 women in a real-world registry.ResultsRSClin provided significantly more prognostic information than either the clinicopathologic factors (ΔLR chi-square, 86.2; P<0.001) or RS alone (ΔLR chi-square, 131.0; P<0.001). The model was prognostic in an independent cohort for distant recurrence by 10 years after diagnosis (standardized hazard ratio, 1.56; 95% confidence interval, 1.25 to 1.94), was associated with late distant recurrence risk between 5 and 10 years after diagnosis (standardized hazard ratio, 1.78; 95% confidence interval, 1.25 to 2.55), and approximated the observed 10-year distant recurrence risk (Lin concordance, 0.87) and 5- to 10-year distant recurrence risk (Lin concordance, 0.92).ConclusionsThe 21-gene RS is prognostic for distant recurrence and overall survival in early breast cancer. A model integrating the 21-gene RS and clinicopathologic factors improved estimates of distant recurrence risk compared with either used individually and stratified late distant recurrence risk. (Funded by the National Cancer Institute, National Institutes of Health [U10CA180820, U10CA180794, UG1CA189859, U10CA180868, and U10CA180822] and others.)

Prediction of the number of positive axillary lymph nodes according to sentinel lymph node involvement and biological subtypes in patients receiving neoadjuvant chemotherapy

BackgroundSentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) for assessing axillary lymph node status in clinically node-negative breast cancer patients. However, the approach to axillary surgery after neoadjuvant treatment is still controversial. In the present study, our objective was to predict the pathological nodal stage based on SLNB results and the clinicopathological characteristics of patients who initially presented with clinical N1 positivity but whose disease status was converted to clinical N0 after neoadjuvant chemotherapy (NAC).Materials and methodsAfter NAC, 150 clinically node-negative patients were included. The relationships between clinicopathologic parameters and the number of positive lymph nodes in SLNBs and ALNDs were assessed through binary/multivariate logistic regression analysis.ResultsAmong 150 patients, 78 patients had negative SLNBs, and 72 patients had positive SLNBs. According to the ALND data of 21 patients with SLNB1+, there was no additional node involvement (80.8%), 1–2 lymph nodes were positive in 5 patients (19.2%), and no patient had ≥ 3 lymph nodes involved. Following the detection of SLNB1 + positivity, the rate of negative non-sentinel nodes were 75% in the luminal A/B subgroup, 100% in the HER-2-positive subgroup, and 100% in the triple-negative subgroup. Patients with a lower T stage (T1-3 vs. T4), fewer than 4 clinical nodes before NAC (< 4 vs. ≥4), and a decreased postoperative Ki-67 index (< 10% vs. stable/increase) were included. According to both univariate and multivariate analyses, being in the triple-negative or HER2-positive subgroup, compared to the luminal A/B subgroup (luminal A/B vs. HER2-positive/triple-negative), was found to be predictive of complete lymph node response.ConclusionThe number of SLNB-positive nodes, tumor-related parameters, and response to treatment may predict no additional nodes to be positive at ALND.

21-Gene Recurrence Score and Survival Outcomes in the Phase III Multicenter TAILORx Clinical Trial.

Recurrence score (RS) based on a 21-gene genomic assay is frequently used to estimate risk of distant recurrence for choice of adjuvant chemotherapy in breast cancer. It remains unclear whether RS is an independent prognostic factor for breast cancer-specific survival (BCSS) and overall survival (OS) in the TAILORx trial population. We evaluated the association of RS with BCSS and OS plus recurrence-free interval (RFI) and invasive disease-free survival (DFS) using multivariable Cox proportional hazards regression analysis, adjusting for clinicopathologic measures, in 8,916 patients with hormone receptor-positive, HER2-negative, node-negative breast cancer. Likelihood ratio (LR) test was used to assess the relative amount of prognostic information provided by RS to BCSS, OS, RFI, and DFS, comparatively. Event rates for BCSS, OS, RFI, and DFS were 1.7%, 5.2%, 5.6%, and 12.6%, respectively, by up to 11.6 years of follow-up. Compared with low-range RS (0-10), patients with midrange (11-25) and high-range (26-100) RS had inferior BCSS (adjusted hazard ratio [aHR], 5.12 [95% CI, 2.09-16.92] and 8.03 [95% CI, 2.91-28.47], respectively) and RFI (aHR, 1.68 [95% CI, 1.23-2.36] and 3.05 [95% CI, 2.02-4.67], respectively), independent of clinicopathologic factors. High-range score was associated with an increased risk of DFS (aHR, 1.56 [95% CI, 1.20-2.04]) but not significantly associated with OS (aHR, 1.44 [95% CI, 0.95-2.18]). Midrange score was associated with neither DFS (aHR, 1.15 [95% CI, 0.96-1.38]) nor OS (HR 1.14 [95% CI, 0.87-1.52]). LR-χ2 values were 83.0 and 65.1 for RFI and BCSS, respectively, and 17.5 and 33.6 for OS and DFS, respectively (P<.0001). RS is an independent measure for BCSS and recurrence prognoses relative to OS in early-stage breast cancer. It carries more prognostic information for breast cancer-specific outcomes.

Electronic Health Record–Based Nudge Intervention and Axillary Surgery in Older Women With Breast Cancer

Choosing Wisely recommendations advocate against routine use of axillary staging in older women with early-stage, clinically node-negative (cN0), hormone receptor-positive (HR+), and HER2-negative breast cancer. However, rates of sentinel lymph node biopsy (SLNB) in this population remain persistently high. To evaluate whether an electronic health record (EHR)-based nudge intervention targeting surgeons in their first outpatient visit with patients meeting Choosing Wisely criteria decreases rates of SLNB. This nonrandomized controlled trial was a hybrid type 1 effectiveness-implementation study with subsequent postintervention semistructured interviews and lasted from October 2021 to October 2023. Data came from EHRs at 8 outpatient clinics within an integrated health care system; participants included 7 breast surgical oncologists. Data were collected for female patients meeting Choosing Wisely criteria for omission of SLNB (aged ≥70 years with cT1 and cT2, cN0, HR+/HER2- breast cancer). The study included a 12-month preintervention control period; baseline surveys assessing perceived acceptability, appropriateness, and feasibility of the designed intervention; and a 12-month intervention period. A column nudge was embedded into the surgeon's schedule in the EHR identifying patients meeting Choosing Wisely criteria for potential SLNB omission. The primary outcome was rate of SLNB following nudge deployment into the EHR. Similar baseline demographic and tumor characteristics were observed before (control period, n = 194) and after (intervention period, n = 193) nudge deployment. Patients in both the control and intervention period had a median (IQR) age of 75 (72-79) years. Compared with the control period, unadjusted rates of SLNB decreased by 23.1 percentage points (46.9% SLNB rate prenudge to 23.8% after; 95% CI, -32.9 to -13.8) in the intervention period. An interrupted time series model showed a reduction in the rate of SLNB following nudge deployment (adjusted odds ratio, 0.26; 95% CI, 0.07 to 0.90; P = .03). The participating surgeons scored the intervention highly on acceptability, appropriateness, and feasibility. Dominant themes from semistructured interviews indicated that the intervention helped remind the surgeons of potential Choosing Wisely applicability without the need for additional clicks or actions on the day of the patient visit, which facilitated use. This study showed that a nudge intervention in the EHR significantly decreased low-value axillary surgery in older women with early-stage, cN0, HR+/HER2- breast cancer. This user-friendly and easily implementable EHR-based intervention could be a beneficial approach for decreasing low-value care in other practice settings or patient populations. ClinicalTrials.gov Identifier: NCT06006910.

Predictive value of MRI-based deep learning model for lymphovascular invasion status in node-negative invasive breast cancer

To retrospectively assess the effectiveness of deep learning (DL) model, based on breast magnetic resonance imaging (MRI), in predicting preoperative lymphovascular invasion (LVI) status in patients diagnosed with invasive breast cancer who have negative axillary lymph nodes (LNs). Data was gathered from 280 patients, including 148 with LVI-positive and 141 with LVI-negative lesions. These patients had undergone preoperative breast MRI and were histopathologically confirmed to have invasive breast cancer without axillary LN metastasis. The cohort was randomly split into training and validation groups in a 7:3 ratio. Radiomics features for each lesion were extracted from the first post-contrast dynamic contrast-enhanced (DCE)-MRI. The Least Absolute Shrinkage and Selection Operator (LASSO) regression method and logistic regression analyses were employed to identify significant radiomic features and clinicoradiological variables. These models were established using four machine learning (ML) algorithms and one DL algorithm. The predictive performance of the models (radiomics, clinicoradiological, and combination) was assessed through discrimination and compared using the DeLong test. Four clinicoradiological parameters and 10 radiomic features were selected by LASSO for model development. The Multilayer Perceptron (MLP) model, constructed using both radiomic and clinicoradiological features, demonstrated excellent performance in predicting LVI, achieving a high area under the curve (AUC) of 0.835 for validation. The DL model (MLP-radiomic) achieved the highest accuracy (AUC = 0.896), followed by DL model (MLP-combination) with an AUC of 0.835. Both DL models were significantly superior to the ML model (RF-clinical) with an AUC of 0.720. The DL model (MLP), which integrates radiomic features with clinicoradiological information, effectively aids in the preoperative determination of LVI status in patients with invasive breast cancer and negative axillary LNs. This is beneficial for making informed clinical decisions.

Preoperative prediction of nodal status using clinical data and artificial intelligence derived mammogram features enabling abstention of sentinel lymph node biopsy in breast cancer.

Patients with clinically node-negative breast cancer have a negative sentinel lymph node status (pN0) in approximately 75% of cases and the necessity of routine surgical nodal staging by sentinel lymph node biopsy (SLNB) has been questioned. Previous prediction models for pN0 have included postoperative variables, thus defeating their purpose to spare patients non-beneficial axillary surgery. We aimed to develop a preoperative prediction model for pN0 and to evaluate the contribution of mammographic breast density and mammogram features derived by artificial intelligence for de-escalation of SLNB. This retrospective cohort study included 755 women with primary breast cancer. Mammograms were analyzed by commercially available artificial intelligence and automated systems. The additional predictive value of features was evaluated using logistic regression models including preoperative clinical variables and radiological tumor size. The final model was internally validated using bootstrap and externally validated in a separate cohort. A nomogram for prediction of pN0 was developed. The correlation between pathological tumor size and the preoperative radiological tumor size was calculated. Radiological tumor size was the strongest predictor of pN0 and included in a preoperative prediction model displaying an area under the curve of 0.68 (95% confidence interval: 0.63-0.72) in internal validation and 0.64 (95% confidence interval: 0.59-0.69) in external validation. Although the addition of mammographic features did not improve discrimination, the prediction model provided a 21% SLNB reduction rate when a false negative rate of 10% was accepted, reflecting the accepted false negative rate of SLNB. This study shows that the preoperatively available radiological tumor size might replace pathological tumor size as a key predictor in a preoperative prediction model for pN0. While the overall performance was not improved by mammographic features, one in five patients could be omitted from axillary surgery by applying the preoperative prediction model for nodal status. The nomogram visualizing the model could support preoperative patient-centered decision-making on the management of the axilla.