Intraoperative sentinel node biopsy by one-step nucleic acid amplification (OSNA) avoids axillary lymphadenectomy in women with breast cancer treated with neoadjuvant chemotherapy

Sentinel lymph node biopsy before and after neoadjuvant chemotherapy in cN0 breast cancer patients: impact on axillary morbidity and survival-a propensity score cohort study

PURPOSE

In patients with clinically lymph node-negative (cN0) breast cancer, performing sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NACT) has been preferentially embraced in comparison to before NACT. However, survival outcomes associated with both strategies remain understudied. We aimed to compare the axillary lymphadenectomy (ALND) rate, disease-free survival (DFS), and overall survival (OS), between two strategies.

METHODS

We included 310 patients in a retrospective observational study. SNLB was performed before NACT from December 2006 to April 2014 (107 cases) and after NACT from May 2014 to May 2020 (203 patients). An inverse probability of treatment weighting (IPTW) method was applied to homogenize both groups. Hazard ratios (HR) and odd ratios (OR) are reported with 95% confidence intervals (95%CI).

RESULTS

The lymphadenectomy rate was 29.9% before NACT and 7.4% after NACT (p < 0.001), with an OR of 5.35 95%CI (2.7-10.4); p = .002. After 4 years of follow-up, SLNB after NACT was associated with lower risk for DFS, HR 0.42 95%CI (0.17-1.06); p = 0.066 and better OS, HR 0.21 CI 95% (0.07-0.67); p = 0.009 than SLNB before NACT. After multivariate analysis, independent adverse prognostic factors for OS included SLNB before NACT, HR 3.095 95%CI (2.323-4.123), clinical nonresponse to NACT, HR 1.702 95% CI (1.012-2.861), and small tumors (cT1) with high proliferation index, HR 1.889 95% (1.195-2.985).

CONCLUSION

Performing SLNB before NACT results in more ALND and has no benefit for patient survival. These findings support discontinuing the practice of SLNB before NACT in patients with cN0 breast cancer.

Validation of prognostic and predictive value of total tumoral load after primary systemic therapy in breast cancer using OSNA assay

PURPOSE

This study aimed to validate the classification of breast cancer (BC) patients in progression risk groups based on total tumor load (TTL) value to predict lymph node (LN) affectation after neo-adjuvant systemic therapy (NAST) obtained in the NEOVATTL study.

METHODS/PATIENTS

This was an observational, retrospective, international, multicenter study including patients with infiltrating BC who received NAST followed by sentinel lymph node biopsy (SLNB) analyzed with one-step nucleic acid amplification (OSNA) from nine Spanish and two Italian hospitals. Patients were classified into three groups according to the progression risk, measured as disease-free survival (DFS), based on TTL values (> 250, 250-25,000, and > 25,000 copies/μL). The previous (NEOVATTL study) Cox regression model for prognosis was validated using prognostic index (PI) and Log ratio test (LRT) analyses; the value of TTL for axillary non-SLN affectation was assessed using receiver operating characteristic (ROC) curves.

RESULTS

We included 263 patients with a mean age of 51.4 (± SD 10.5) years. Patients with TTL > 25,000 copies/μL had a shorter DFS (HR 3.561 [95% CI 1.693-7.489], p = 0.0008 vs. TTL ≤ 25,000). PI and LRT analyses showed no differences between the two cohorts (p = 0.2553 and p = 0.226, respectively). ROC analysis showed concordance between TTL and non-SLN involvement (area under the curve 0.828), with 95.7% sensitivity and 92.9% specificity at a TTL cut-off of > 15,000 copies/μL.

CONCLUSIONS

In BC patients who had received NAST and underwent SLNB analysis using OSNA, a TTL value of > 25,000 copies/μL was associated with a higher progression risk and > 15,000 copies/μL was predictive of non-SLN involvement.

Development of MRI-Based Deep Learning Signature for Prediction of Axillary Response After NAC in Breast Cancer

RATIONALE AND OBJECTIVES

To develop a MRI-based deep learning signature for predicting axillary response after neoadjuvant chemotherapy (NAC) in breast cancer (BC) patients.

MATERIALS AND METHODS

We enrolled 327 BC patients with axillary lymph node (ALN) metastases receiving axillary operations after NAC. The deep learning features were extracted by ResNet34, which was pretrained by a large, well-annotated dataset from ImageNet. Then we identified deep learning radiomics on magnetic resonance imaging with dynamic contrast enhancement (DCE-MRI) in predicting axillary response after NAC in BC patients.

RESULTS

The extraction of 128 deep learning radiomics (DLR) features relied on the DCE-MRI for each patient. After the least absolute shrinkage and selection operator regression analysis, 13, 8, and 21 features remained from the pre-treatment, post-treatment, and combined DCE-MRI, respectively. The DLR signature established based on the combined DCE-MRI achieved good capacity in ALN response after NAC. The support vector machine achieved the best performance with an 0.99 area under the curve (AUC) of (95% confidence interval (CI), 0.98-1.00) and 0.83 (95% CI, 0.73-0.92) in the training and test sets, respectively. The LR model established with clinical parameters represented the best performance with 0.73 AUC (95% CI, 0.62-0.84), 0.73 sensitivity, 0.73 specificity, 0.63 PPV, and 0.81 NPV in the test set, respectively. Finally, the integration of radiomic signature and clinical signature resulted in establishing a predictive radiomic nomogram, with an AUC of 0.99 (95%CI, 0.99-1.00).

CONCLUSION

In conclusion, our current study constructed a predictive nomogram through the deep learning method, demonstrating favorable performance in the training and test cohort. The present prognostic model furnishes a precise and objective foundation for directing the surgical strategy toward ALN management in BC patients receiving NAC.

Nonsentinel Axillary Lymph Node Status in Clinically Node-Negative Early Breast Cancer After Primary Systemic Therapy and Positive Sentinel Lymph Node: A Predictive Model Proposal

BACKGROUND

In clinically node-negative (cN0) early stage breast cancer (EBC) undergoing primary systemic treatment (PST), post-treatment positive sentinel lymph node (SLN+) directs axillary lymph node dissection (ALND), with uncertain impacts on outcomes and increased morbidities.

PATIENTS AND METHODS

We conducted an observational study on imaging-confirmed cN0 EBC, who underwent PST and breast surgery that resulted in SLN+ and underwent ALND. The association among baseline/postsurgical clinic-pathological factors and positive nonsentinel additional axillary lymph nodes (non-SLN+) was analyzed with logistic regression. LASSO regression (LR) identified variables to include in a predictive score of non-SLN+ (ALND-predict). The accuracy and calibration were assessed, an optimal cut-point was then identified, and in silico validation with bootstrap was undertaken.

RESULTS

Non-SLN+ were detected in 22.2% cases after ALND. Only progesterone receptor (PR) levels and macrometastatic SLN+ were independently associated to non-SLN+. LR identified PR, Ki67, and type and number of SLN+ as the most efficient covariates. The ALND-predict score was built based on their LR coefficients, showing an area under the curve (AUC) of 0.83 and an optimal cut-off of 63, with a negative predictive value (NPV) of 0.925. Continuous and dichotomic scores had a good fit (p = 0.876 and p = 1.00, respectively) and were independently associated to non-SLN+ [adjusted odds ratio (aOR): 1.06, p = 0.002 and aOR: 23.77, p < 0.001, respectively]. After 5000 bootstrap-adjusted retesting, the estimated bias-corrected and accelerated 95%CI included the aOR.

CONCLUSIONS

In cN0 EBC with post-PST SLN+, non-SLN+ at ALND are infrequent (~22%) and independently associated to PR levels and macrometastatic SLN. ALND-predict multiparametric score accurately predicted absence of non-SLN involvement, identifying most patients who could be safely spared unnecessary ALND. Prospective validation is required.

Value of total tumor load as a clinical and pathological factor in the prognosis of breast cancer patients receiving neoadjuvant treatment. Comparison of three populations with three different surgical approaches: NEOVATTL Pro 3 Study

PURPOSE

This study aimed to compare the prognosis in terms of disease-free survival (DFS) in three populations of women with breast cancer (BC) treated with neoadjuvant systemic treatment (NAST) in which axillary lymph node dissection (ALND) was performed based on different total tumor load (TTL) thresholds in the sentinel nodes.

METHODS

This was an observational, retrospective study carried out in three Spanish centers. Data from patients with infiltrating BC who underwent BC surgery after NAST and intraoperative sentinel lymph node biopsy (SLNB) performed by One Step Nucleic acid Amplification (OSNA) technique during 2017 and 2018 were analyzed. ALND was performed according to the protocol of each center, based on three different TTL cut-offs (TTL > 250, TTL > 5000, and TTL > 15,000 CK19-mRNA copies/μL for centers 1, 2, and 3, respectively).

RESULTS

A total of 157 BC patients were included in the study. No significant differences in DFS were observed between centers (Hazard ratio [HR] center 2 vs 1: 0.77; p = 0.707; HR center 3 vs 1: 0.83; p = 0.799). Patients with ALND had a shorter DFS (HR 2.43; p = 0.136), albeit not statistically significant. Patients with a triple negative subtype had a worse prognosis than those with other molecular subtypes (HR 2.82; p = 0.056).

CONCLUSION

No significant differences in DFS were observed between three centers with different surgical approaches to ALND based on different TTL cut-offs in patients with BC after NAST. These results suggest that restricting ALND to those patients with TTL ≥ 15,000 copies/μL is a reliable approximation, avoiding unnecessary morbidities caused by ALND.

Predictive and prognostic value of total tumor load in sentinel lymph nodes in breast cancer patients after neoadjuvant treatment using one-step nucleic acid amplification: the NEOVATTL study

Objective

To evaluate the predictive and prognostic value of total tumor load (TTL) in sentinel lymph nodes (SLNs) in patients with infiltrating breast cancer after neoadjuvant systemic therapy (NST).

Methods

This retrospective multicenter study used data from a Spanish Sentinel Lymph Node database. Patients underwent intraoperative SLN biopsy after NST. TTL was determined from whole nodes using a one-step nucleic acid amplification (OSNA) assay and defined as the total sum of CK19 mRNA copies in all positive SLNs. Cox-regression models identified independent predictive variables, which were incorporated into a nomogram to predict axillary non-SLN metastasis, and identified prognostic variables for incorporation into a disease-free survival (DFS) prognostic score.

Results

A total of 314 patients were included; most had no lymph node involvement prior to NST (cN0; 75.0% of patients). Most received chemotherapy with or without biologic therapy (91.7%), and 81 patients had a pathologic complete response. TTL was predictive of non-SLN involvement (area under the concentration curve = 0.87), and at a cut-off of 15,000 copies/µL had a negative predictive value of 90.5%. Nomogram parameters included log (TTL + 1), maximum tumor diameter and study-defined NST response. TTL was prognostic of disease recurrence and DFS at a cut-off of 25,000 copies/µL. After a 5-year follow-up, DFS was higher in patients with ≤ 25,000 copies/µL than those with > 25,000 (89.9% vs. 70.0%; p = 0.0017).

Conclusions

TTL > 15,000 mRNA copies/µL was predictive of non-SLN involvement and TTL > 25,000 mRNA copies/µL was associated with a higher risk of disease recurrence in breast cancer patients who had received NST.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12094-020-02530-4.

A nomogram to predict non-sentinel lymph node metastasis in patients with initial cN+ breast cancer that downstages to cN0 after neoadjuvant chemotherapy

BACKGROUND AND OBJECTIVES

This study mainly explored the factors that influence non-sentinel lymph node (NSLN) metastasis in patients with breast cancer (BC) whose axillary lymph nodal status changed from clinically node positive (cN+) to clinically node negative (cN0) after neoadjuvant chemotherapy (NAC).

METHODS

We retrospectively analyzed the clinicopathological factors affecting NSLN metastasis in a total of 179 patients with cN+ BC downstaged to cN0 (120 in the training set and 59 in the validation set) who underwent both sentinel lymph node (SLN) biopsy and axillary lymph node dissection following NAC.

RESULTS

Among 179 patients enrolled, the overall NSLN metastatic rate was 24.0% (95% confidence interval [CI]: 17.7%-30.3%). In multivariate logistic regression analysis, the number of positive SLNs achieving a pathological complete remission of the breast and clinical node staging was independent predictors of NSLN metastasis. A nomogram was established based on these factors and displayed a good discriminatory capability, with an area under the curve of 0.919 (95% CI: 0.865-0.973) for the training set and 0.900 (95% CI: 0.812-0.988) for the validation set and its clinical utility was confirmed by the decision curve analysis.

CONCLUSIONS

The nomogram established showed the ability to predict NSLN metastases in patients with initial cN+ BC that downstaged to cN0 after NAC.

Improved Model for Predicting Axillary Response to Neoadjuvant Chemotherapy in Patients with Clinically Node-Positive Breast Cancer

Purpose

Pathological complete response (pCR) of axillary lymph node (LN) is frequently achieved in patients with clinically node-positive breast cancer after neoadjuvant chemotherapy (NAC). Treatment of the axilla after NAC is not well established and the value of sentinel LN biopsy following NAC remains unclear. This study investigated the predictive value of axillary response following NAC and evaluated the predictive value of a model based on axillary response.

Methods

Data prospectively collected on 201 patients with clinically node-positive breast cancer who were treated with NAC and underwent axillary LN dissection (ALND) were retrieved. A model predictive of axillary pCR was developed based on clinicopathologic variables. The overall predictive ability between models was compared by receiver operating characteristic (ROC) curve analysis.

Results

Of 201 patients who underwent ALND after NAC, 68 (33.8%) achieved axillary pCR. Multivariate analysis using axillary LN pCR after NAC as the dependent variable showed that higher histologic grade (p=0.031; odds ratio [OR], 2.537; 95% confidence interval [CI], 1.087–5.925) and tumor response rate ≥47.1% (p=0.001; OR, 3.212; 95% CI, 1.584–6.515) were significantly associated with an increased probability of achieving axillary pCR. The area under the ROC curve for estimating axillary pCR was significantly higher in the model that included tumor response rate than in the model that excluded this rate (0.732 vs. 0.649, p=0.022).

Conclusion

Tumor response rate was the most significant independent predictor of axillary pCR in response to NAC. The model that included tumor response rate was a significantly better predictor of axillary pCR than the model that excluded tumor response rate.

Redox status in the sentinel lymph node of women with breast cancer

BACKGROUND

Lymphatic metastasis is regulated in multiple steps including the transit of tumor cells via the lymphatic vessels and the successful seeding in draining lymph nodes. Thus, several molecular signals and cellular changes must be involved in this complex process to facilitate tumor cell entry, colonization, and survival in the lymph node. To our knowledge, the present work explores, for the first time in the literature, the redox status (oxidative stress parameters and enzymatic and non-enzymatic antioxidant defense systems) in the sentinel lymph node (SLN) of women with breast cancer.

PATIENTS AND METHODS

SLNs from 75 women with breast cancer were identified using the one-step nucleic acid amplification (OSNA) method as negative (n = 43), with micrometastases (n = 13), or with macrometastases (n = 19). It will allow us to gain knowledge about the pro-oxidant/antioxidant mechanisms involved in the processes of distant metastases in breast cancer and also to assess whether these parameters may be alternative techniques for staging.

RESULTS

We found different levels of lipid peroxidation in SLNs with micrometastases (increased) and macrometastases (decreased), a decrease in carbonyl group content in SLNs with macrometastases only, and an increase in total antioxidant capacity (TAC) in SNLs with micrometastases and macrometastases. A decrease in the levels of reduced glutathione (GSH) also appears in the SLNs with macrometastases only. Finally, we show increased levels of superoxide dismutase (SOD) and catalase (CAT) activity in SLNs with micrometastases and macrometastases, and decreased levels of glutathione peroxidase (GPx) activity in SNLs with macrometastases but not with micrometastases.

CONCLUSIONS

Redox status of lymph node microenvironment participates in the progression of metastatic breast cancer.

Intraoperative assessment of sentinel lymph node by one-step nucleic acid amplification in breast cancer patients after neoadjuvant treatment reduces the need for a second surgery for axillary lymph node dissection

PURPOSE

Sentinel lymph node (SLN) biopsy has been shown to be both accurate and feasible for women who receive neoadjuvant chemotherapy (NAC). Intraoperative assessment of SLN by frozen sections can produce false negative results. The aim of this study was to compare two different techniques of intraoperative assessment of SLN in breast cancer patients treated with NAC: frozen section (FS) and molecular assay (OSNA).

METHODS

A multicenter cohort of 320 consecutive breast cancer patients treated with NAC between 2010 and 2014 was analyzed. FS was performed intraoperatively in 166 patients (H&E cohort) and OSNA in 154 patients (OSNA cohort).

RESULTS

A mean of 2.15 SLNs by FS and 1.22 SLNs by OSNA was assessed (p = 0.03). SLN metastasis was found in 44 patients (26.5%) by FS and in 48 (31.2%) by OSNA (p = 0.4). There was no statistical significance in rates of macrometastasis (75%), micrometastasis (20.5%) or ITCs (4.5%) when assessed by FS compared to OSNA (52.3%, 36.3% and 11.4%, respectively) (p = 0.06). There were 10 patients in the H&E cohort with positive-SLN in the definitive pathology assessment with negative intraoperative FS. When OSNA and definitive pathology were compared, there were no differences in rates of macrometastasis (61.1%), micrometastasis (33.3%) nor ITCs (5.6%) (p = 0.5). Fifty-four patients in the H&E cohort and 44 in the OSNA cohort had ALND after positive-SLNs. ALND was performed in a second surgery in 10 patients (18.5%) in the H&E cohort for intraoperative FS false negative results, 90% being micrometastasis. 42 out of 44 patients (95.5%) in the OSNA cohort had an ALND in the same surgery (p = 0.03).

CONCLUSIONS

OSNA assay detects SLNs metastases as accurately as conventional pathology in the NAC setting. Intraoperative definitive assessment of the SLN by OSNA reduces the need for a second surgery for ALND in 18.5% of breast cancer patients with a positive-SLN after NAC.

[Sentinel node biopsy after neoadjuvant chemotherapy in breast cancer. Its relation with molecular subtypes]

OBJECTIVE

To evaluate the influence of the molecular subtype (MS) in the Sentinel Node Biopsy (SNB) technique after neoadjuvant chemotherapy (NAC) in women with locally advanced breast cancer (BC) and a complete axillary response (CR).

MATERIAL AND METHODS

A prospective study involving 70 patients with BC treated with NAC was carried out. An axillary lymph node dissection was performed in the first 48 patients (validation group: VG), and in case of micro- or macrometastases in the therapeutic application phase (therapy group:TG). Classified according to MS: 14 luminal A; 16 luminal B HER2-, 13 luminal B HER2+, 10HER2+ non-luminal, 17 triple-negative.

RESULTS

SNB was carried out in 98.6% of the cases, with only one false negative result in the VG (FN=2%). Molecular subtype did not affect SN detection. Despite the existence of axillary CR, statistically significant differences were found in the proportion of macrometastasis (16.7% vs. 35.7%, p=0.043) on comparing the pre-NAC cN0 and cN+. Breast tumor response to NAC varied among the different MS, this being lowest in luminal A (21.5%) and highest in non-luminal HER2+ group (80%). HER2+ and triple-negative were the groups with the best axillary histological response both when there was prior clinical involvement and when there was not.

CONCLUSIONS

Molecular subtype is a predictive factor of the degree of tumor response to NAC in breast cancer. However, it does not affect SNB detection and efficiency. SNB can also be used safely in women with prior node involvement as long as a complete clinical and radiological assessment is made of the node response to NAC.