Feasibility, accuracy and prognosis of sentinel lymph node biopsy before neoadjuvant therapy in breast cancer. A prospective study

Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy in cN0 Breast Cancer: Impact of HER2-Positive Status on Survival

Objective

High rates of negative sentinel lymph node biopsy (SLNB) in clinically node-negative (cN0) breast cancer (BC) after neoadjuvant chemotherapy (NAC) have been described. These results are associated with triple-negative (TNBC) and human epidermal growth factor receptor 2 (HER2+) subtypes achieving pathologic complete response (pCR). This study evaluates predictive variables and survival in order to assess the possible omission of SLNB after NAC.

Materials and Methods

Prospective study of women with cN0 BC treated with NAC and subsequent surgery, between April 2010 and May 2021. SLNB technique included, performing axillary lymphadenectomy in the absence of detection or SLNB-positivity. Multivariable logistic regression was used for analysis of NAC-response and SLNB-results in molecular subtypes: HR-/HER2+, TNBC, HR+/HER2- and HR+/HER2+. Kaplan-Meyer and log-rank were used for survival analysis.

Results

A total of 179 patients (50.5±10.1 years) were included. Of these, 39.7% achieved pCR (ypT0/Tis). HR-negative subtypes had higher pCR rates (HR-/HER2+: 59.4%; TNBC: 53.4%), with no cases of SLNB-positive. With residual disease, HR-/HER2+ and TNBC showed low rates of SLNB-positivity (6.7% and 10.3%) versus HR+ (HR+/HER2+: 20%; HR+/HER2-: 44%; p<0.001). Multivariable analysis identified independent predictors of SLNB-negativity (p<0.0001) to be: HR- [odds ratio (OR)=0.15; 95% confidence interval (CI): 0.06-0.37; p = 0.0001], HER2+ (OR=0.34; 95% CI: 0.14-0.81; p = 0.015) and high-grade Nottingham (OR=0.42; 95% CI: 0.18-0.99; p = 0.048). Disease-free survival showed worse outcomes with SLNB-positivity (p<0.0001), HR+/HER2- (p = 0.0277), larger tumor size (p = 0.002) and residual disease after NAC (p<0.0001).

Conclusion

Patient selection based on NAC response, molecular subtype, and survival outcomes is a priority for establishing individualized therapeutic strategies after NAC. Molecular subtypes with higher pCR rates and lower rates of SLNB-positivity could benefit from non-invasive strategies that include omission of SLNB.

Clinical study of combined application of indocyanine green and methylene blue for sentinel lymph node biopsy in breast cancer

OBJECTIVE

This study aims to investigate the feasibility of combined application of indocyanine green (ICG) and methylene blue (MB) for sentinel lymph node biopsy (SLNB) in patients with early breast cancer.

METHODS

A total of 415 patients who underwent SLNB and axillary lymph node dissection were enrolled. Sentinel lymph node (SLN) was assessed in 197 patients with ICG and MB combination method, while, the other 218 patients were detected by MB method alone. During surgery, all SLNs were harvested for pathological examination. Then the detection rate and false negative rate of SLNs were comparatively analyzed between the 2 groups.

RESULTS

In the combined ICG and MB group, the detection rate of SLNs was 96.9%, significantly higher than that of MB group, which was 89.7% (P < .05). Similarly, in combined group, the average number of SLNs per patient was 3.0, much higher than that of MB group, which was 2.1 (P < .05). There was no statistically significant difference in false negative rate between combined group and MB alone group, which was 7.3% and 10.5%, respectively (P = .791).

CONCLUSION

The combined application of ICG and MB for SLNB is much more effective than MB alone in detecting SLNs.

Development and validation of a nomogram for prediction of lymph node metastasis in early-stage breast cancer

Background

Lymph node status is an important factor in determining the prognosis of early-stage breast cancer. We endeavored to build and validate a simple nomogram to predict lymph node metastasis (LNM) in patients with early-stage breast cancer.

Methods

Patients with T1-2 and non-metastasis (M0) breast cancer registered in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. All patients were divided into primary cohort and validation cohort in a 2:1 ratio. In order to assess risk factors for LNM, we performed univariate and multivariate binary logistic regression, and based on results of multivariable analysis, we built the predictive nomogram model. The C-index, receiver operating characteristic (ROC) and calibration plots were applied to assess LNM model performance. Moreover, the nomogram efficiency was further validated through the validation cohort, part of which was from the First Affiliated Hospital of Nanjing Medical University database.

Results

Totally, 184,531 female breast cancer with T1-2 tumor size from SEER database and 1,222 patients from the Chinese institutional data were included. There were 123,019 patients in the primary cohort and 62,734 patients in validation cohort. The LNM nomogram was composed of seven features including age at diagnosis, race, primary site, histologic type, grade, tumor size and subtype. The model showed good discrimination, with a C-index of 0.720 [95% confidence interval (CI): 0.717-0.723] and good calibration. Similar C-index was 0.718 (95% CI: 0.713-0.723) in validation cohort. Consistently, ROC curves presented good discrimination in the primary cohort [area under the curve (AUC) =0.720] and the validation set (AUC =0.718) for the LNM nomogram. Calibration curve of the nomogram demonstrated good agreement.

Conclusions

With the prediction of novel validated nomogram for women with early-stage breast cancer, doctors may distinguish patients with high possibility of LNM and devise individualize treatments.

[Risk of axillary recurrence after sentinel lymph node biopsy before neoadjuvant chemotherapy in breast cancer]

OBJECTIVES

In case of large breast cancer, neoadjuvant chemotherapy (NAC) can be performed to reduce the size of the tumor and thus perform a conservative surgery. The place of the sentinel lymph node biopsy (SLNB) in case of NAC is still debated. The main aim of this study is to assess the risk of axillary recurrence after negative SLNB before NAC.

METHODS

It is a retrospective, observational and uni-centric study. We included 18 to 80-year-old patients with unilateral breast cancer requiring a NAC and with a negative SLNB before NAC. Our primary endpoint was axillary recurrence.

RESULTS

Between August 2006 and October 2016, 64 patients had a negative GS performing before a NAC and did not benefit from axillary dissection after NAC. The average duration of follow-up was 37 months. During our follow-up, we did not find any cases of axillary recurrence.

CONCLUSION

This study supports the reliability of lymph node status assessment using the SLNB before CNA.

Validation of Breast Cancer Models for Predicting the Nonsentinel Lymph Node Metastasis After a Positive Sentinel Lymph Node Biopsy in a Chinese Population

Objectives:

Over the years, completion axillary lymph node dissection is recommended for the patients with breast cancer if sentinel lymph node metastasis is found. However, not all of these patients had nonsentinel lymph node metastasis on final histology. Some predicting models have been developed for calculating the risk of nonsentinel lymph node metastasis. The aim of our study was to validate some of the predicting models in a Chinese population.

Method:

Two hundred thirty-six patients with positive sentinel lymph node and complete axillary lymph node dissection were included. Patients were applied to 6 models for evaluation of the risk of nonsentinel lymph node involvement. The receiver–operating characteristic curves were shown in our study. The calculation of area under the curves and false negative rate was done for each model to assess the discriminative power of the models.

Results:

There are 105 (44.5%) patients who had metastatic nonsentinel lymph node(s) in our population. Primary tumor size, the number of metastatic sentinel lymph node, and the proportion of metastatic sentinel lymph nodes/total sentinel lymph nodes were identified as the independent predictors of nonsentinel lymph node metastasis. The Seoul National University Hospital and Louisville scoring system outperformed the others, with area under the curves of 0.706 and 0.702, respectively. The area under the curve values were 0.677, 0.673, 0.432, and 0.674 for the Memorial Sloan-Kettering Cancer Center, Tenon, Stanford, and Shanghai Cancer Hospital models, respectively. With adjusted cutoff points, the Louisville scoring system outperformed the others by classifying 26.51% of patients with breast cancer to the low-risk group.

Conclusion:

The Louisville and Seoul National University Hospital scoring system were found to be more predictive among the 6 models when applied to the Chinese patients with breast cancer in our database. Models developed at other institutions should be used cautiously for decision-making regarding complete axillary lymph node dissection after a positive biopsy in sentinel lymph node.

Neoadjuvant chemotherapy for breast cancer-background for the indication of locoregional treatment

Neoadjuvant chemotherapy (NACT) has been widely adopted into the multidisciplinary management of breast cancer. The prognostic impact of treatment response has been clearly demonstrated. However, the impact of treatment response on the indication for adjuvant radiotherapy is unclear. This review summarizes important implications of NACT and treatment response on the risk of recurrence and locoregional multidisciplinary management from the standpoint of radiation oncology.