Predictors of positive axillary lymph nodes after sentinel lymph node biopsy in breast cancer

Correlation between sentinel lymph node biopsy and non-sentinel lymph node metastasis in patients with cN0 breast carcinoma: comparison of invasive ductal carcinoma and invasive lobular carcinoma

BACKGROUND

Some studies have suggested that axillary lymph node dissection (ALND) can be avoided in women with cN0 breast cancer with 1-2 positive sentinel nodes (SLNs). However, these studies included only a few patients with invasive lobular carcinoma (ILC), so the validity of omitting ALDN in these patients remains controversial. This study compared the frequency of non-sentinel lymph nodes (non-SLNs) metastases in ILC and invasive ductal carcinoma (IDC).

MATERIALS METHODS

Data relating to a total of 2583 patients with infiltrating breast carcinoma operated at our institution between 2012 and 2023 were retrospectively analyzed: 2242 (86.8%) with IDC and 341 (13.2%) with ILC. We compared the incidence of metastasis to SLNs and non-SLNs between the ILC and IDC cohorts and examined factors that influenced non-SLNs metastasis.

RESULTS

SLN biopsies were performed in 315 patients with ILC and 2018 patients with IDC. Metastases to the SLNs were found in 78/315 (24.8%) patients with ILC and in 460 (22.8%) patients with IDC (p = 0.31). The incidence of metastases to non-SLNs was significantly higher (p = 0.02) in ILC (52/78-66.7%) compared to IDC (207/460 - 45%). Multivariate analysis showed that ILC was the most influential predictive factor in predicting the presence of metastasis to non-SLNs.

CONCLUSIONS

ILC cases have more non-SLNs metastases than IDC cases in SLN-positive patients. The ILC is essential for predicting non-SLN positivity in macro-metastases in the SLN. The option of omitting ALND in patients with ILC with 1-2 positive SLNs still requires further investigation.

A machine-learning approach based on multiparametric MRI to identify the risk of non-sentinel lymph node metastasis in patients with early-stage breast cancer

BACKGROUND

It has been reported that patients with early breast cancer with 1-2 positive sentinel lymph nodes have a lower risk of non-sentinel lymph node (NSLN) metastasis and cannot benefit from axillary lymph node dissection.

PURPOSE

To develop the potential of machine learning based on multiparametric magnetic resonance imaging (MRI) and clinical factors for predicting the risk of NSLN metastasis in breast cancer.

MATERIAL AND METHODS

This retrospective study included 144 patients with 1-2 positive sentinel lymph node breast cancer. Multiparametric MRI morphologic findings and the detailed demographical characteristics of the primary tumor and axillary lymph node were extracted. The logistic regression, support vector classification, extreme gradient boosting, and random forest algorithm models were established to predict the risk of NSLN metastasis. The prediction efficiency of a machine-learning-based model was evaluated. Finally, the relative importance of each input variable was analyzed for the best model.

RESULTS

Of the 144 patients, 80 (55.6%) developed NSLN metastasis. A total of 24 imaging features and 14 clinicopathological features were analyzed. The extreme gradient boosting algorithm had the strongest prediction efficiency with an area under curve of 0.881 and 0.781 in the training set and test set, respectively. Five main factors for the metastasis of NSLN were found, including histological grade, cortical thickness, fatty hilum, short axis of lymph node, and age.

CONCLUSION

The machine-learning model incorporating multiparametric MRI features and clinical factors can predict NSLN metastasis with high accuracy for breast cancer and provide predictive information for clinical protocol.

Contemporary approaches to the axilla in breast cancer

Over the past decade, axillary management in breast cancer has fundamentally shifted. The former notion that any degree of axillary nodal involvement warrants axillary lymph node dissection (ALND) has been challenged. Following publication of the ACOSOG Z0011 trial, national trends demonstrated significant reductions in ALND performance. Axillary radiotherapy in lieu of ALND is a consideration for select patients with a positive sentinel lymph node, while ongoing studies are investigating the role of adjuvant regional radiotherapy in women with positive nodes prior to neoadjuvant chemotherapy. Efforts toward de-escalation of axillary surgery continue to evolve, as do the indications for sentinel node biopsy omission in select subsets of patients. This review highlights the recent advances and neoteric approaches to local therapy of the axilla in breast cancer.

Trends in axillary surgery and clinical outcomes among breast cancer patients with sentinel node metastasis

Background

There is a lack of studies examining the long-term trend and survival of axillary surgery for breast cancer patients with sentinel node metastasis, especially for the patients with 3–5 node metastases.

Methods

Breast cancer patients with 1–5 sentinel node metastases from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2016. Our study presented the trend of axillary surgery and assessed the long-term survival of sentinel lymph node biopsy (SLNB) alone vs axillary lymph node dissection (ALND) for those patients.

Results

Of the 41,996 patients diagnosed with T_1-2 breast cancer after lumpectomy and radiation included, 34,940 had 1-2 sentinel node metastases and 7056 had 3-5 sentinel node metastases. The percentage of patients undergoing SLNB alone increased from 22.4% in 2000 to 81.0% in 2016 for patients with 1–2 sentinel node metastases, and quadrupled from 5.2% in 2009 to 20.6% in 2016 for those with 3–5 sentinel node metastases. Completion of ALND did not benefit the long-term survival of 1–2 sentinel node metastasis patients (hazard ratio [HR] = 1.02, P = 0.539), but improved the long-term survival of 3–5 node metastasis patients (HR = 0.73, P < 0.001). Subgroup analysis demonstrated the inferiority of SLNB to ALND in all subgroups of 3–5 sentinel node metastases.

Conclusion

For patients with T_1-2 breast cancer after lumpectomy and radiation, SLNB alone was an efficient and safe surgical choice for 1–2 sentinel node metastases but not for 3–5 sentinel node metastases. It is worth noting that for patients with 3–5 node metastasis, the proportion of omitted ALND quadrupled after 2009.

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Using SEER database, the research presents the long-term trend and survival of axillary surgery for breast cancer patients with 1-2 and 3-5 sentinel nodes metastasis.

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For patients with T1-2 breast cancer after lumpectomy and radiation, SLNB alone was efficient for 1–2 sentinel node metastases but not for 3–5 sentinel node metastases.

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Among patients with 3–5 node metastasis, the proportion of omitted ALND quadrupled from 2009 to 2016.

Application of the Machine-Learning Model to Improve Prediction of Non-Sentinel Lymph Node Metastasis Status Among Breast Cancer Patients

Background

Performing axillary lymph node dissection (ALND) is the current standard option after a positive sentinel lymph node (SLN). However, whether 1–2 metastatic SLNs require ALND is debatable. The probability of metastasis in non-sentinel lymph nodes (NSLNs) can be calculated using nomograms. In this study, we developed an individualized model using machine-learning (ML) methods to select potential variables, which influence NSLN metastasis.

Materials and Methods

Cohorts of patients with early breast cancer who underwent SLN biopsy and ALND between 2012 and 2021 were created (training cohort, N 157 and validation cohort, N 58) for the development of the nomogram. Three ML methods were trained in the training set to create a strong predictive model. Finally, the multiple iterations of the least absolute shrinkage and selection operator regression method were used to determine the variables associated with NSLN status.

Results

Four independent variables (positive SLN number, absence of lymph node hilum, lymphovascular invasion (LVI), and total number of SLNs harvested) were combined to generate the nomogram. The area under the receiver operating characteristic curve (AUC) value of 0.759 was obtained in the entire set. The AUC values for the training set and the test set were 0.782 and 0.705, respectively. The Hosmer-Lemeshow test of the model fit accuracy was identified with p = 0.759.

Conclusion

This study developed a nomogram that incorporates ultrasound (US)-related variables using the ML method and serves to clinically predict the non-metastatic status of NSLN and help in the selection of the appropriate treatment option.

Predictive factors of non-sentinel lymph node disease in breast cancer patients with positive sentinel lymph node

INTRODUCTION

Management of positive sentinel lymph node biopsy (SLNB) in breast cancer remains a matter of debate. Our aim was to evaluate the incidence and identify predictive factors of non-sentinel lymph node metastases.

METHODS

Retrospective review of all cN0 breast cancer patients treated between January 2013 and December 2017, with positive SLNB that were submitted to ALND.

RESULTS

Of the 328 patients included, the majority of tumors were cT1 or cT2, with lymphovascular invasion in 58.4% of cases. The mean isolated nodes in SLNB was 2.7, with a mean of 1.6 positive nodes, 60.7% with extracapsular extension. Regarding ALND, a mean of 13.9 nodes were isolated, with a mean of 2.1 positive nodes. There was no residual disease in the ALND in 50.9% of patients, with 18.9% having ≥4 positive nodes. In the multivariate analysis, lymphovascular invasion, extracapsular extension in SLN, largest SLN metastases size (>10 mm) and ratio of positive SNL (>50%) were independent predictors of non-sentinel lymph node metastases. These four factors were used to build a non-pondered score to predict the probability of a positive ALND after a positive SLNB. The AUC of the model was 0.69 and 81% of patients with score = 0 and 65.6% with score = 1 had no additional disease in ALND.

CONCLUSION

The absence of non-sentinel lymph node metastases in the majority of patients with 1-2 positive SLN with low risk score questions the need of ALND in this population. The identified predictive factors may help select patients in which ALND can be omitted.

Candidates of Genomic Tests in HR+/HER2- Breast Cancer Patients With 1-2 Positive Sentinel Lymph Node Without Axillary Lymph Node Dissection: Analysis From Multicentric Cohorts

Background

The genomic tests such as the MammaPrint and Oncotype DX test are being gradually applied for hormone receptor positive/HER-2 negative (HR+/HER2-) breast cancer patients with up to three positive axillary lymph nodes (ALNs). The first results from RxPONDER trial suggested that Oncotype DX could be applied to patients with 1-2 positive sentinel lymph nodes (SLNs) without axillary lymph node dissection (ALND), which constituted 37.4% of the intent-to-treat population. However, there was no distinctive research on how to apply genomic tests precisely to HR+/HER2- patients with 1-2 positive SLNs without ALND. The purpose was to construct a nomogram using the multi-center retrospective data to predict precisely which HR+/HER2- candidates with 1-2 positive SLNs could be subjected to genomic tests (≤ 3 positive lymph nodes).

Methods

We conducted a retrospective analysis of 18,600 patients with stage I-III breast cancer patients treated with sentinel lymph node biopsy (SLNB) in Shandong Cancer Hospital, Fudan University Shanghai Cancer Center, and West China Hospital. The univariate and multivariate logistic regression analysis was conducted to identify the independent predictive factors of having ≤ 3 positive nodes among patients with 1-2 positive SLNs. A nomogram was developed based on variables in the final model with p<0.05. Calibration of the nomogram was carried out by internal validation using the bootstrap resampling approach and was displayed using a calibration curve. The discrimination of the model was evaluated using the ROC curve.

Results

Based on the database of the three institutions, a total of 18,600 breast cancer patients were identified undergoing SLNB between May 2010 and 2020. Among the 1817 HR+/HER2- patients with 1-2 positive SLNs undergoing ALND, 84.2% harbored ≤ 3 totals metastatic ALNs. The multivariate logistic regression analysis identified imaging abnormal nodes (OR=0.197, 95%CI: 0.082-0.472), the number of positive SLNs (OR=0.351, 95%CI: 0.266-0.464), the number of negative SLNs (OR=1.639, 95%CI: 1.465-1.833), pathological tumor stage (OR=0.730, 95%CI: 0.552-0.964), and lympho-vascular invasion (OR=0.287, 95%CI: 0.222-0.398) as independent predictors for the proportion of patients with ≤ 3 total metastatic ALNs (all p<0.05). These five predictors were used to create a predictive nomogram. The AUC value was 0.804 (95%CI: 0.681-0.812, p<0.001). The calibration curve showed a satisfactory fit between the predictive and actual observation based on internal validation with a bootstrap resampling frequency of 1000.

Conclusion

The nomogram based on the multi-centric database showed a good accuracy and could assist the oncologist in determining precisely which HR+/HER2- candidates with 1-2 positive SLNs without ALND could perform genomic tests. In the era of SLNB and precision medicine, the combined application of genomic tests and SLNB could provide patients with a better strategy of dual de-escalation management, including the de-escalation of both surgery and systemic treatment.

Prognostic value of extranodal extension in axillary lymph node-positive breast cancer

Several studies have demonstrated that extranodal extension (ENE) is associated with prognosis in breast cancer. Whether this association should be described in pathological reports warrants further investigation. In this research, we evaluated the predictive value of ENE in axillary lymph nodes (ALNs) in invasive breast cancer and explored the feasibility of employing ENE to predict clinicopathological features, nodal burden, disease recurrence-free survival (DRFS) and overall survival (OS) in clinical practice. In addition, the cutoff values of perpendicular diameter ENE (PD-ENE) and circumferential diameter ENE (CD-ENE) of ENE were investigated. A total of 402 cases of primary invasive breast cancer were extracted from Fudan University Shanghai Cancer Center; these patients underwent axillary lymph node dissection (ALND) between 2010 and 2015. ENE in the ALN was defined as the tumor cells breaking through the lymph node capsule into peripheral adipose tissue and causing connective tissue reactions. Relationships between ENE and clinicopathological features, nodal burden, disease recurrence-free survival (DRFS) and overall survival (OS) were analyzed. PD-ENE was defined by measuring from the point where tumor tissue broke the node capsule to the highest point of the tumor cells in the perinodal adipose tissue.K The average PD-ENE was 1.8 mm; therefore, we divided ENE-positive patients into two groups: PD-ENE no greater than 2 mm and PD-ENE greater than 2 mm. CD-ENE was defined as measuring along the nodal capsule as the distance between peripheral edges of the ENE area. According to the average circumferential diameter (CD-ENE), we classified ENE-positive patients into two groups: CD-ENE no greater than 3 mm and CD-ENE greater than 3 mm. Correlations between ENE cutoffs and prognosis were analyzed. In this cohort of patients, 158 (39.3%) cases were positive for ENE in ALN.98 (24.4%) cases had PD-ENE no larger than 2 mm, and 60 (14.9%) cases had PD-ENE larger than 2 mm. Also, 112 (27.9%) cases had CD-ENE no larger than 3 mm, and 46 (11.4%) cases had CD-ENE larger than 3 mm. Statistical analysis indicated that histological grade, N stage, and HER2 overexpression subtype were associated with ENE. The presence of ENE had significant statistical correlations with nodal burden, including N stage, median metastatic tumor diameter and peri-lymph node vascular invasion (p < 0.001, p < 0.001, p = 0.001, respectively). Cox regression analysis demonstrated that patients with ENE exhibited significantly reduced DRFS in both univariable analysis (HR 2.126, 95% CI 1.453–3.112, p < 0.001) and multivariable analysis (HR 1.745, 95% CI 1.152–2.642, p = 0.009) compared with patients without ENE. For overall survival (OS), patients with ENE were associated with OS in univariable analysis (HR 2.505, 95% CI 1.337–4.693, p = 0.004) but not in multivariable analysis (HR 1.639, 95% CI 0.824–3.260, p = 0.159). Kaplan–Meier curves and log-rank test showed that patients with ENE in ALN had lower DRFS and OS (for DRFS: p < 0.0001; and for OS: p = 0.002, respectively). However, neither the PD-ENE group (divided by 2 mm) nor the CD-ENE group (divided by 3 mm) exhibited significant differences regarding nodal burden and prognosis. Our study indicated that ENE in the ALN was a predictor of prognosis in breast cancer. ENE was an independent prognostic factor for DRFS and was associated with OS. ENE in the ALN was associated with a higher nodal burden. The size of ENE, which was classified by a 3-mm (CD-ENE) or 2-mm (PD-ENE) cutoff value, had no significant prognostic value in this study. Based on our findings, the presence of ENE should be included in routine pathological reports of breast cancers. However, the cutoff values of ENE warrant further investigation.

Development and validation of nomograms for predicting axillary non-SLN metastases in breast cancer patients with 1-2 positive sentinel lymph node macro-metastases: a retrospective analysis of two independent cohorts

BACKGROUND

It is reported that appropriately 50% of early breast cancer patients with 1-2 positive sentinel lymph node (SLN) micro-metastases could not benefit from axillary lymph node dissection (ALND) or breast-conserving surgery with whole breast irradiation. However, whether patients with 1-2 positive SLN macro-metastases could benefit from ALND remains unknown. The aim of our study was to develop and validate nomograms for assessing axillary non-SLN metastases in patients with 1-2 positive SLN macro-metastases, using their pathological features alone or in combination with STMs.

METHODS

We retrospectively reviewed pathological features and STMs of 1150 early breast cancer patients from two independent cohorts. Best subset regression was used for feature selection and signature building. The risk score of axillary non-SLN metastases was calculated for each patient as a linear combination of selected predictors that were weighted by their respective coefficients.

RESULTS

The pathology-based nomogram possessed a strong discrimination ability for axillary non-SLN metastases, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.727 (95% CI: 0.682-0.771) in the primary cohort and 0.722 (95% CI: 0.653-0.792) in the validation cohort. The addition of CA 15-3 and CEA can significantly improve the performance of pathology-based nomogram in the primary cohort (AUC: 0.773 (0.732-0.815) vs. 0.727 (0.682-0.771), P < 0.001) and validation cohort (AUC: (0.777 (0.713-0.840) vs. 0.722 (0.653-0.792), P < 0.001). Decision curve analysis demonstrated that the nomograms were clinically useful.

CONCLUSION

The nomograms based on pathological features can be used to identify axillary non-SLN metastases in breast cancer patients with 1-2 positive SLN. In addition, the combination of STMs and pathological features can identify patients with patients with axillary non-SLN metastases more accurately than pathological characteristics alone.

Clinical implications of intrinsic molecular subtypes of breast cancer for sentinel node status

Axillary lymph node status is an important prognostic factor for breast cancer patients and sentinel lymph node biopsy (SLNB) is a less invasive surgical proxy. We examined if consecutively derived molecular subtypes from primary breast cancers provide additional predictive value for SLNB status. 1556 patients with a breast cancer > 10 mm underwent primary surgical procedure including SLNB and tumor specimens were assigned with a transcriptomics-based molecular subtype. 1020 patients had a negative sentinel node (SN) and 536 a positive. A significant association between tumor size and SN status (p < 0.0001) was found across all samples, but no association between size and SN status (p = 0.14) was found for BasL tumors. A BasL subtype was a predictor of an SN-negative status (p = 0.001, OR 0.58, 95% CI 0.38;0.90) and among the BasL, postmenopausal status was a predictor for SN-negative status (p = 0.01). Overall survival was significantly lower (p = 0.02) in patients with BasL tumors and a positive SN. Interestingly, we identified a significant correlation between hormone receptor activity and SN status within the BasL subtype. Taken together, molecular subtypes and hormone receptor activity of breast cancers add predictive value for SLNB status.

Predictive factors of non-sentinel lymph node disease in breast cancer patients with positive sentinel lymph node

INTRODUCTION

Management of positive sentinel lymph node biopsy (SLNB) in breast cancer remains a matter of debate. Our aim was to evaluate the incidence and identify predictive factors of non-sentinel lymph node metastases.

METHODS

Retrospective review of all cN0 breast cancer patients treated between January 2013 and December 2017, with positive SLNB that were submitted to ALND.

RESULTS

Of the 328 patients included, the majority of tumors were cT1 or cT2, with lymphovascular invasion in 58.4% of cases. The mean isolated nodes in SLNB was 2.7, with a mean of 1.6 positive nodes, 60.7% with extracapsular extension. Regarding ALND, a mean of 13.9 nodes were isolated, with a mean of 2.1 positive nodes. There was no residual disease in the ALND in 50.9% of patients, with 18.9% having ≥ four positive nodes. In the multivariate analysis, lymphovascular invasion, extracapsular extension in SLN, largest SLN metastases size (>10 mm) and ratio of positive SNL (> 50%) were independent predictors of non-sentinel lymph node metastases. These four factors were used to build a non-pondered score to predict the probability of a positive ALND after a positive SLNB. The AUC of the model was 0.69 and 81% of patients with score = 0 and 65.6% with score = 1 had no additional disease in ALND.

CONCLUSION

The absence of non-sentinel lymph node metastases in the majority of patients with 1-2 positive SLN with low risk score questions the need of ALND in this population. The identified predictive factors may help select patients in which ALND can be omitted.

Axillary staging based on molecular analysis: Results of the B-CLOSER-II study

INTRODUCTION

Axillary staging (pN) is a strong predictor of outcome in early stage breast cancer yet following the publication of the Z0011 trial there has been an increasing tendency to spare lymph node dissection. Automated molecular detection of cytokeratin 19mRNA by one-step nucleic acid amplification (OSNA) has been demonstrated to be an accurate method to assess sentinel lymph node (SLN) metastasis. In this study we compare histological and molecular methods following complete axillary lymph node dissection (cALND), determine whether molecular axillary staging affects survival, and evaluate the predictive and prognostic value of total tumor load in ALND (AD-TTL) and in all positive nodes (G-TTL).

MATERIAL AND METHODS

Axillary lymph nodes were collected from 102 patients with primary breast cancer with histological confirmation of axillary involvement (cN+) or positive SLN. The central 1-mm portion of each non-SLN was processed for hematoxylin-eosin staining and the remaining tissue was analyzed by OSNA.

RESULTS

Non-SLNs were diagnosed as positive in 72 out of 102 patients (70.6 %) on OSNA compared with only 53 (52 %) on histology (p < 0.01). Thirteen patients would have changed staging if the diagnoses provided had been by molecular methods (p < 0.01), but without a change in prognosis. AD-TTL and G-TTL were predictive of recurrence and mortality.

CONCLUSIONS

Compared to molecular detection, histological examination significantly underestimates the frequency of axillary node metastases. However, the increase in pN did not show a clinical effect on survival in those patients.

Associated Features with Non-Sentinel Lymph Node Involvement in Early Stage Breast Cancer Patients who Have Positive Macrometastatic Sentinel Lymph Node

Objective

The main goal of this study is to determine the clinico-pathological factors that correlate non-sentinel lymph nodes (LNs) involvement in clinically node negative breast cancer (BC) patients with positive macrometastatic sentinel lymph node (SLN) in order to derive future evidence to define a subgroup where completion axillary lymph node dissection (cALND) might not be recommended.

Materials and Methods

Total 289 SLN biopsies were performed in clinically node negative BC patients between March 2014 and April 2017. Seventy patients who performed cALND due to positive macrometastatic SLN were retrospectively selected and classified into two groups, according to non-SLN involvement (NSLNI). Clinico-pathological features of patients were examined computerized and documentary archives.

Results

Extracapsular extension (ECE) of SLN, number of harvested SLNs, metastatic rate of SLNs, absence of ductal carcinoma in situ (DCIS) and presence of multilocalization were significantly associated with the likelihood of non-SLN involvement after univariate analysis (p<0,05). Absence of DCIS and presence of multilocalization were found to be significant after multivariate analysis.

Conclusion

Careful examination of clinico-pathological features can help to decide avoiding cALND if enough LNs are removed and the rate of SLN metastases is low, particularly in case DCIS accompanying invasive cancer in patients without multi localized tumour.

Extranodal Tumor Deposits in the Axillary Fat Indicate the Need for Axillary Dissection Among T1-T2cN0 Patients with Positive Sentinel Nodes

BACKGROUND

The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial demonstrated the safety of omitting axillary lymph node dissection (ALND) in T1-T2cN0 patients with fewer than three positive sentinel nodes (SLNs) undergoing breast-conservation therapy. While microscopic extracapsular extension (mECE) > 2 mm is associated with increased nodal burden, the significance of extranodal tumor deposits (ETDs) in the axillary fat is uncertain.

METHODS

Consecutive patients with T1-T2cN0 breast cancer undergoing sentinel node biopsy and ALND for SLN metastases from January 2010 to December 2018 were identified. ETDs were defined as intravascular tumor emboli or metastatic deposits in the axillary fat. Clinicopathologic characteristics and nodal burden were compared by ETD status.

RESULTS

Among 1114 patients, 113 (10%) had ETDs: 81 (72%) were intravascular tumor emboli and 32 (28%) were soft tissue deposits. Patients with ETDs had larger tumors (median 2.2 vs. 2.1 cm; p = 0.033) and more often had mECE (83% vs. 44%; p < 0.001). On univariable analysis, presence of ETDs (odds ratio [OR] 9.66, 95% confidence interval [CI] 6.36-14.68), larger tumors (OR 1.47, 95% CI 1.25-1.72), and mECE (OR 10.73, 95% CI 6.86-16.78) were associated with four or more additional positive non-SLNs (NSLNs; all p < 0.001). On multivariable analysis, ETDs remained associated with four or more positive NSLNs (OR 5.67, 95% CI 3.53-9.08; p < 0.001). ETDs were strongly associated with four or more positive NSLNs (OR 7.15, 95% CI 4.04-12.67) among patients with one to two positive SLNs (n = 925).

CONCLUSIONS

Among T1-T2cN0 patients with SLN metastases, ETDs are strongly associated with four or more positive NSLNs at ALND. Even among those who may otherwise meet the criteria for omission of ALND, the presence of ETDs in axillary fat warrants consideration of ALND.

Predictors of nonsentinel lymph node metastasis in patients with breast cancer with metastasis in the sentinel node

To predict the factors related to axillary nonsentinel lymph node (NSLN) metastasis in patients with positive sentinel lymph node (SLN) of early breast cancer.The retrospective data are collected from the patients with positive SLN who received further completion axillary lymph node dissection (cALND) in Peking Union Medical Hospital between March 2016 and December 2017. Univariate analysis was conducted on data with various clinicopathologic factors at first. Those factors with statistic significance (P < .05) in univariate analysis were then used to implement multivariate analysis and logistic regression.There were total of 734 patients who received SLN biopsy , among whom 153 cases were included in our study. About 39.22% (60/153) of 153 paitents with positive SLN had no NSLN metastasisted to SLN. Univariate analysis showed that 3 variables were significantly correlated with NSLN involvement: tumor size (X = 10.384, P = .001), SLN metastasis ratio (number of positive SLNs/number of SLNs removed × 100%) (X = 10.365, P = .001) and the number of negative sentinel nodes (X = 10.384, P = .006). In multivariate analysis and logistic regression, tumor size (odds ratio [OR] = 3.392, 95% confidence interval [CI]: 1.409-8.166, P = .006) and SLN metastasis ratio (OR = 3.514, 95% CI: 1.416-8.72, P = .007) were the independent risk factors. While the number of negative sentinel nodes (OR = 0.211, 95% CI: 0.063-0.709, P = .014) was the independent protective factor. The calculated risk resulted in an area under the curve of 0.746 (95% CI: 0.644-0.848), suggesting stable discriminative capability in Chinese population.For those patients with positive SLN, larger tumor burden and SLN metastasis ratio are independent risk factors for NSLN metastasis. However, the more of the detected negative SLN, the less possibility with NSLN involvement.

Associations between obesity, smoking and lymph node status at breast cancer diagnosis in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial

INTRODUCTION

There is evidence suggesting that smoking and obesity prior to a breast cancer diagnosis is associated with poorer outcomes. In this study, we investigate the associations between smoking and obesity prior to a breast cancer diagnosis and the presence of lymph node metastases at diagnosis.

METHODS

Women with stage I-III breast cancer (n = 3,304) were identified from the National Cancer Institute's Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Univariable and multivariable log-binomial models were used to estimate relative risks (RR) and 95% confidence intervals (CIs) for associations between lymph node positive breast cancer and; i) smoking, and ii) obesity prior to diagnosis.

RESULTS

Pre-diagnostic smoking/obesity was not associated with lymph node metastasis at diagnosis in multivariable analyses; (RR 0.82, 95%CI 0.61, 1.10) and (RR 0.95, 95% CI 0.81, 1.12), respectively.

CONCLUSION

Obesity and smoking information was recorded a number of years prior to breast cancer diagnosis, therefore these findings should to be replicated in a larger cohort of women, with more detailed smoking and obesity information.

Is completion axillary lymph node dissection necessary in patients who are underrepresented in the ACOSOG Z0011 trial?

PURPOSE

The American College of Surgeons Oncology Group trial Z0011 demonstrated that axillary node dissection (ALND) can be omitted in patients managed with breast conserving surgery and 1 to 2 positive sentinel lymph nodes (SLNs) without adverse effects on locoregional recurrence or disease-free survival (DFS). We investigated patients with breast cancer for whom clinicopathologic features were underrepresented in the Z0011 trial and analyzed radiation therapy treatment patterns and clinical outcomes.

METHODS AND MATERIALS

We retrospectively reviewed records of patients who underwent a lumpectomy and SLN biopsy with positive SLNs but not an ALND and completed adjuvant radiation therapy. Eligible patients had T3 tumors, >2 positive SLNs, invasive lobular carcinoma, estrogen receptor negative status, extranodal extension, Nottingham Grade 3, or were age <50 years.

RESULTS

We identified 105 women treated between July 2011 and July 2016 with a median follow-up time of 48.5 months (Range, 11-83 months). There were 40 women with an extranodal extension (38.9%) and 42 women with grade 3 disease (40.0%). Nineteen patients received whole breast irradiation alone (18.1%) and 86 patients were treated with modified tangent fields including the superior axilla level I/II (81.9%). Thirty-three patients (31.4%) also received a 3rd supraclavicular, nodal-directed field. Among the 86 patients who received axillary nodal irradiation, nodal volume contouring was performed in 77 patients (89.5%). Fifty-one patients (48.6%) also received adjuvant chemotherapy. The overall rates of 4-year DFS and locoregional control (LRC) were 94.3% and 98.1%, respectively. Off all patients, 1 patient experienced an internal mammary nodal recurrence, another patient a contralateral breast tumor, and two patients distant metastases. There were no axillary or ipsilateral breast tumor recurrences.

CONCLUSIONS

This retrospective analysis of women who were underrepresented or excluded from the Z11 trial and underwent a lumpectomy and SLN biopsy with positive SLNs demonstrated comparable rates of LRC and DFS. The high rates of LRC and DFS suggest that completion ALND may be safely omitted in this patient population but larger data sets and longer follow-up times are needed to confirm this finding.

A mathematical prediction model incorporating molecular subtype for risk of non-sentinel lymph node metastasis in sentinel lymph node-positive breast cancer patients: a retrospective analysis and nomogram development

BACKGROUND

Molecular subtype of breast cancer is associated with sentinel lymph node status. We sought to establish a mathematical prediction model that included breast cancer molecular subtype for risk of positive non-sentinel lymph nodes in breast cancer patients with sentinel lymph node metastasis and further validate the model in a separate validation cohort.

METHODS

We reviewed the clinicopathologic data of breast cancer patients with sentinel lymph node metastasis who underwent axillary lymph node dissection between June 16, 2014 and November 16, 2017 at our hospital. Sentinel lymph node biopsy was performed and patients with pathologically proven sentinel lymph node metastasis underwent axillary lymph node dissection. Independent risks for non-sentinel lymph node metastasis were assessed in a training cohort by multivariate analysis and incorporated into a mathematical prediction model. The model was further validated in a separate validation cohort, and a nomogram was developed and evaluated for diagnostic performance in predicting the risk of non-sentinel lymph node metastasis. Moreover, we assessed the performance of five different models in predicting non-sentinel lymph node metastasis in training cohort.

RESULTS

Totally, 495 cases were eligible for the study, including 291 patients in the training cohort and 204 in the validation cohort. Non-sentinel lymph node metastasis was observed in 33.3% (97/291) patients in the training cohort. The AUC of MSKCC, Tenon, MDA, Ljubljana, and Louisville models in training cohort were 0.7613, 0.7142, 0.7076, 0.7483, and 0.671, respectively. Multivariate regression analysis indicated that tumor size (OR = 1.439; 95% CI 1.025-2.021; P = 0.036), sentinel lymph node macro-metastasis versus micro-metastasis (OR = 5.063; 95% CI 1.111-23.074; P = 0.036), the number of positive sentinel lymph nodes (OR = 2.583, 95% CI 1.714-3.892; P < 0.001), and the number of negative sentinel lymph nodes (OR = 0.686, 95% CI 0.575-0.817; P < 0.001) were independent statistically significant predictors of non-sentinel lymph node metastasis. Furthermore, luminal B (OR = 3.311, 95% CI 1.593-6.884; P = 0.001) and HER2 overexpression (OR = 4.308, 95% CI 1.097-16.912; P = 0.036) were independent and statistically significant predictor of non-sentinel lymph node metastasis versus luminal A. A regression model based on the results of multivariate analysis was established to predict the risk of non-sentinel lymph node metastasis, which had an AUC of 0.8188. The model was validated in the validation cohort and showed excellent diagnostic performance.

CONCLUSIONS

The mathematical prediction model that incorporates five variables including breast cancer molecular subtype demonstrates excellent diagnostic performance in assessing the risk of non-sentinel lymph node metastasis in sentinel lymph node-positive patients. The prediction model could be of help surgeons in evaluating the risk of non-sentinel lymph node involvement for breast cancer patients; however, the model requires further validation in prospective studies.

A quantitative analysis of tumour characteristics in breast cancer patients with extranodal extension in non-sentinel nodes

BACKGROUND

The presence of extranodal extension (ENE) is well documented as a predictor of non-sentinel lymph node (NSLN) metastasis. The ACOSOG Z0011 trial (2011) concluded that patients who satisfy criteria including the absence of sentinel lymph node (SLN) ENE can forgo axillary clearance (AC). Currently there are no studies analysing the rate of ENE in NSLN metastasis in which the sentinel node was positive but had no ENE. Determining this incidence will help determine if current paradigms are resulting in residual ENE in NSLN metastasis by forgoing AC based on the Z0011 trial..

METHODS

This study determined incidence of ENE at NSLN metastasis in patients with a positive SLN biopsy without ENE in 162 symptomatic breast cancer patients who underwent AC between 2009 and 2014 at Cork University Hospital Breast Cancer Service, a teaching hospital of University College Cork.

RESULTS

Of 965 sentinel node biopsies performed 251 were identified as SLN positive, 162 (64.5%) underwent further AC. Of the 162 patients, 56.8% (92/162) were positive for ENE at SLN, of these 57.6% (53/92) had NSLN metastasis versus 17.1% (12/70) in the ENE-negative group (χ² test; P < 0.001). On adjusted analysis, ENE at the SLN was a significant predictor of NSLN metastasis (odds ratio [OR] 8.63; 95% confidence interval [CI] 3.26-22.86; P < 0.001). The incidence of NSLN-ENE in patients without SLN-ENE was 1/70 (1.4%) compared with 33.7% (31/92) in patients who had ENE at the SLN (χ² test; P < 0.001).

CONCLUSION

ENE at the SLN is an independent predictor of NSLN involvement; its absence significantly reduces the likelihood of ENE in NSLN metastasis..

The predictive value of methylene blue dye as a single technique in breast cancer sentinel node biopsy: a study from Dharmais Cancer Hospital

Background

Axillary lymph node dissection (ALND) has been the standard treatment of breast cancer axillary staging in Indonesia. The limited facilities of radioisotope tracer and isosulfan or patent blue dye (PBD) have been the major obstacles to perform sentinel node biopsy (SNB) in our country. We studied the application of 1% methylene blue dye (MBD) alone for SNB to overcome the problem.

Methods

This prospective study enrolled 108 patients with suspicious malignant lesions or breast cancer stages I–III. SNB was performed using 2–5 cc of 1% MBD and proceeded with ALND. The histopathology results of sentinel nodes (SNs) were compared with axillary lymph nodes (ALNs) for diagnostic value assessments.

Results

There were 96 patients with invasive carcinoma from July 2012 to September 2014 who were included in the final analysis. The median age was 50 (25–69) years, and the median pathological tumor size was 3 cm (1–10). Identification rate of SNs was 91.7%, and the median number of the identified SNs was 2 (1–8). Sentinel node metastasis was found in 53.4% cases and 89.4% of them were macrometastases. The negative predictive value (NPV) of SNs to predict axillary metastasis was 90% (95% CI, 81–99%). There were no anaphylactic reactions, but we found 2 cases with skin necrosis.

Conclusions

The application of 1% MBD as a single technique in breast cancer SNB has favorable identification rates and predictive values. It can be used for axillary staging, but nevertheless the technique should be applied with attention to the tumor size and grade to avoid false negative results.

The Pre-Treatment Neutrophil-Lymphocyte Ratio: a Useful Tool in Predicting Non-Sentinel Lymph Node Metastasis in Breast Cancer Cases

Background:

The sentinel lymph node (SLN) biopsy is a highly accurate predictor of overall axillary nodal status in early breast cancer patients. There is however, still a debate on which patients with a positive SLN can benefit from axillary lymph node dissection (ALND). Numerous studies have been designed to identify variables that are predictive of non-SLN metastasis to avoid a complete ALND. The aim of this study was to determine whether the pre-treatment neutrophil-lymphocyte ratio (NLR) can be a predictive factor of non-SLN metastasis in early breast cancer patients.

Materials and Methods:

The records of 214 consecutive patients with cT1-3N0 invasive breast cancer who had undergone intraoperative SLN evaluation at Songklanagarind Hospital between the 1st of March 2011 and the 30th of May 2016 were examined. Data on patient demographics, tumor variables and NLR were collected and factors for non-SLN metastasis were analyzed using multivariate logistic regression. The power of the NLR was quantified with receiver operating characteristics (ROC) curves as measured by the areas under curves (AUC).

Results:

Multivariate analysis established presence of lymphovascular invasion (OR 8.4, 95%CI 2.3-31.3, p=0.002), macrometastasis (OR 6.6, 95%CI 1.8-24.7, p=0.005), and NLR (OR 2.3, 95%CI 1.1-4.8, p=0.033) as predictive factors of non-SLN metastasis with statistical significance. The AUC for NLR was 0.7 (95%CI 0.6-0.8) with an optimal cut-off of 2.6 giving a sensitivity of 62%, a specificity of 83.8%, a positive predictive value of 77.3% and a negative predictive value of 70.5%.

Conclusion:

Pre-treatment NLR is a useful diagnostic aid for predicting additional non-SLN metastasis.

Predictive factors for the occurrence of four or more axillary lymph node metastases in ER-positive and HER2-negative breast cancer patients with positive sentinel node: A retrospective cohort study

INTRODUCTION

Patients with four or more axillary lymph node metastases have benefited from postmastectomy radiotherapy to the supraclavicular region. However, when metastatic sentinel nodes (SNs) are present, information regarding the total number of node metastases cannot be obtained if axillary lymph node dissection (ALND) is omitted from the treatment protocol. It is important to determine the indication for additional chemotherapy in ER-positive and HER2-negative breast cancer patients. We investigated the predictive factors for the occurrence of four or more metastases in patients with ER-positive and HER2-negative breast cancer in the presence of macrometastasis in the SNs.

METHODS

We reviewed 83 patients with ER-positive and HER2-negative breast cancer, who had macrometastasis in the SN and had undergone ALND. The clinicopathological findings and prognosis between patients with pN1 disease and those with pN2 disease were also compared.

RESULTS

Nineteen percent of patients had pN2-3 disease. The predictive factor for poor prognosis in these patients was the presence of pN2-3 disease. The independent predictive factors for pN2-3 disease were the T stage and the ratio of the number positive SNs to the number of removed SNs (SN ratio). Patients with both T2 tumors and a high SN ratio had a 50% risk of having pN2-3 disease.

CONCLUSION

The presence of four or more metastases was found to be the strongest prognostic factor in ER-positive and HER2-negative breast cancer patients with macrometastasis in the SN. The T stage and SN ratio determined before surgery or during surgery were useful in predicting pN2-3 disease in these patients.

Molecular biomarkers screened by next-generation RNA sequencing for non-sentinel lymph node status prediction in breast cancer patients with metastatic sentinel lymph nodes

BACKGROUND

Non-sentinel lymph node (NSLN) status prediction with molecular biomarkers may make some sentinel lymph node (SLN) positive breast cancer patients avoid the axillary lymph node dissection, but the available markers remain limited.

METHODS

SLN positive patients with and without NSLN invasion were selected, and genes differentially expressed or fused in SLN metastasis were screened by next-generation RNA sequencing.

RESULTS

Six candidates (all ER/PR+, HER2-, Ki-67 <20%) with metastatic SLNs selected from 305 patients were equally categorized as NSLN negative and positive. We identified 103 specifically expressed genes in the NSLN negative group and 47 in the NSLN positive group. Among them, FABP1 (negative group) and CYP2A13 (positive group) were the only 2 protein-encoding genes with expression levels in the 8th to 10th deciles. Using a false discovery rate threshold of <0.05, 62 up-regulated genes and 98 down-regulated genes were discovered in the NSLN positive group. Furthermore, 10 gene fusions were identified in this group with the most frequently fused gene being IGLL5.

CONCLUSIONS

The biomarkers screened in present study may broaden our understanding of the mechanisms of breast cancer metastasis to the lymph nodes and contribute to the axillary surgery selection for SLN positive patients.

Clinicopathologic features predicting involvement of non- sentinel axillary lymph nodes in Iranian women with breast cancer

BACKGROUND

Almost half of the breast cancer patients with positive sentinel lymph nodes have no additional disease in the remaining axillary lymph nodes. This group of patients do not benefit from complete axillary lymph node dissection. This study was designed to assess the clinicopathologic factors that predict non-sentinel lymph node metastasis in Iranian breast cancer patients with positive sentinel lymph nodes.

MATERIALS AND METHODS

The records of patients who underwent sentinel lymph node biopsy, between 2003 and 2012, were reviewed. Patients with at least one positive sentinel lymph node who underwent completion axillary lymph node dissection were enrolled in the present study. Demographic and clinicopathologic characteristics including age, primary tumor size, histological and nuclear grade, lymphovascular invasion, perineural invasion, extracapsular invasion, and number of harvested lymph nodes, were evaluated.

RESULTS

The data of 167 patients were analyzed. A total of 92 (55.1%) had non-sentinel lymph node metastasis. Univariate analysis of data revealed that age, primary tumor size, histological grade, lymphovascular invasion, perineural invasion, extracapsular invasion, and the number of positive sentinel lymph nodes to the total number of harvested sentinel lymph nodes ratio, were associated with non-sentinel lymph node metastasis. After logistic regression analysis, age (OR=0.13; 95% CI, 0.02-0.8), primary tumor size (OR=7.7; 95% CI, 1.4-42.2), lymphovascular invasion (OR=19.4; 95% CI, 1.4- 268.6), extracapsular invasion (OR=13.3; 95% CI, 2.3-76), and the number of positive sentinel lymph nodes to the total number of harvested sentinel lymph nodes ratio (OR=20.2; 95% CI, 3.4-121.9), were significantly associated with non-sentinel lymph node metastasis.

CONCLUSIONS

According to this study, age, primary tumor size, lymphovascular invasion, extracapsular invasion, and the ratio of positive sentinel lymph nodes to the total number of harvested sentinel lymph nodes, were found to be independent predictors of non-sentinel lymph node metastasis.

Predictive factors for additional non-sentinel lymph node involvement in breast cancer patients with one positive sentinel node

AIM

The aim of this study was to identify a subgroup of breast cancer patients in whom it is possible to avoid axillary lymph node dissection (ALND) when the sentinel lymph node (SLN) is positive.

METHODS

A series of 292 patients treated with breast-conserving surgery or mastectomy underwent ALND after positive SLN detection. To correlate SLN metastasis with the chances of finding additional metastasis in non-SLNs we evaluated the main clinicopathological characteristics. No patients received adjuvant radiotherapy to the axillary region.

RESULTS

Fifty-six patients (35.4%) with positive SLNs for macrometastases (n = 158) had additional metastases upon completion ALND compared with 7 patients (5.2%) with micrometastases in the SLN (n = 132). Cases with a higher number of positive axillary lymph nodes tended to have higher pT stage (p = 0.004). In multivariate analysis, pT was confirmed as an independent predictor of non-SLN metastases (OR = 2.40; 95% CI = 1.16-4.99). No patients with micrometastases in SLN and cancer lt;10 mm had additional positive non-SLNs.

CONCLUSIONS

Our results, in agreement with the major published studies, suggest that ALND can be avoided in selected patients without the need for additional treatment to the axillary region.

Extranodal Extension on Sentinel Lymph Node Dissection: Why should we Treat it Differently?

American College of Surgeons Oncology Group Z0011 concluded that axillary lymph node dissection (ALND) may be avoided in selected patients with breast cancer with limited axillary nodal metastasis on sentinel lymph node dissection (SLND). However, patients with extranodal extension (ENE) were excluded to the follow existing standard of care, which is completion ALND. The significance of ENE detected on SLND is not well defined. Our objective was to determine the impact of ENE found on SLND on nonsentinel lymph node (NSLN) metastasis, recurrence, and overall mortality. We evaluated patients with breast cancer treated at a tertiary cancer center from 2005 to 2012. SLND was performed in 655 patients. Of those, 478 of 655 (73.0%) patients had no SLN metastases, 124 of 655 (18.9%) had SLN metastases without ENE (SLN-ENE), and 53 of 655 (8.1%) had SLN metastases with ENE (SLN1ENE). Of patients undergoing ALND, NSLN metastasis was detected in 37 of 84 (44.0%) of patients in the SLN-ENE group and 26 of 45 (57.8%) patients in the SLN1ENE group ( P = 0.14). On adjusted analyses, ENE was associated with increased disease recurrence (odds ratio [OR], 5.48; 95% confidence interval [CI], 1.23 to 24.48; P = 0.03) as well as increased overall mortality (OR, 8.16; 95% CI, 1.72 to 38.63; P = 0.01). In conclusion, ENE is associated with increased overall axillary nodal burden, disease recurrence, and overall mortality.

Histologic evaluation of sentinel and non-sentinel axillary lymph nodes in breast cancer by multilevel sectioning and predictors of non-sentinel metastasis

Sentinel lymph node (SLN) provides accurate nodal staging for breast cancer. This technique has been introduced in Siriraj Hospital since 1998. The goal of this study is to assess its accuracy in predicting the state of the axilla, and compare the results of standard examination and multilevel sectioning. A retrospective analysis of 195 breast cancer patients who underwent both SLN biopsy (using dye alone as the lymphatic mapping) and axillary node dissection during 1998-2002 were analyzed. All slides including SLNs and the non-SLNs (NSLNs) were reviewed and multilevel study was performed on all SLNs and NSLNs [four levels of hematoxylin-eosin (HE) at 200 µm interval and keratin stains on the first and fourth levels]. Of 195 patients, 30% of cases were SLN-positive (32 NSLN-positive and 27 NSLN-negative). Additional study could detect positive axillary nodes 10.8% (4 SLN-positive and 5 NSLN-positive) more than standard HE stain. The false negative rate increased from 20.3% to 24.1%. The concordance between SLN and NSLN statuses was 89.7%. The sensitivity was 75.9%. By multivariate analysis, the significant predictors for axillary node metastasis were tumor size of more than 2.2 cm, histologic type of invasive ductal carcinoma (IDC), not otherwise specified (NOS) and lymphovascular invasion (LVI). By univariable analysis, the significant predictors of NSLN metastasis after positive-SLN were outer location of the tumor, LVI and perinodal extension. In conclusion, use of multilevel and immunohistochemistry increased detection of positive-SLNs. Caution should be kept in accepting SLN biopsy using peritumoral dye technique alone as the procedure for staging due to a high false-negative rate. The concordance rate of 89.7% confirmed the reliability of SLN. Outer location of tumor, LVI and perinodal extension is significant predictors of positive-NSLN after positive-SLN.

Positive sentinel lymph node: the evolution of axillary surgery and intraoperative assessment of sentinel lymph nodes

SUMMARY 

Axillary lymph node dissection (ALND) has been the treatment for breast cancer in patients with sentinel lymph node (SLN) biopsy metastasis for prognostic information, local control and maybe for a small survival benefit. In recent years, clinicians have been questioning the need for axillary dissection in patients with positive SLN as the rate of axillary recurrences remains low when no ALND is performed in this group. Several variables incorporated in nomograms have been examined to predict axillary metastasis in patients with SLN metastasis and these nomograms have helped to determine which patients can spare the morbidity of the ALND. The combined multimodality in breast cancer treatments and the improvement in targeted therapies based in tumor biology have contributed to the low recurrence rates in early-stage breast cancer. As the multimodal treatment and the screening programs will improve, more patients with SLN metastasis will spare an ALND without compromising their oncologic outcome.

An independent assessment of the 7 nomograms for predicting the probability of additional axillary nodal metastases after positive sentinel lymph node biopsy in a cohort of British patients with breast cancer

INTRODUCTION

Axillary lymph node dissection (ALND) is currently the recommended procedure in patients with tumor-positive sentinel lymph node biopsy (SLNB). A significant proportion of patients with positive SLNs will not have any additional metastases in nonsentinel lymph nodes (NSLNs). Predictive nomograms could identify a subgroup of patients with low or high risk of further disease in whom completion ALND can be avoided or recommended. The aim of this study was to assess the accuracy of the currently available 7 nomograms in a cohort of British patients with breast cancer.

PATIENTS AND METHODS

A total of 138 patients with positive SLNs who underwent completion ALND were identified. Data were then used to calculate the probability of further metastases in NSLNs predicted by the 7 nomograms that are currently in use: the MSKCC (Memorial Sloan Kettering Cancer Center), Cambridge, Turkish, Stanford, MDACC (University of Texas MD Anderson Cancer Center), Tenon, and MOU (Masarykuv onkologický ústav, Masaryk Memorial Cancer Institute) models. The area under the receiver operating characteristic (ROC) curve (AUC) was calculated for each nomogram.

RESULTS

Of the 138 patients, 54 (41%) had additional metastases in NSLNs. AUC values for the MSKCC, Cambridge, Turkish, Stanford, MDACC, Tenon, and MOU models are 0.68, 0.68, 0.70, 0.69, 0.56, 0.63, and 0.74, respectively.

CONCLUSION

The MOU nomogram was more predictive than the other nomograms, with a better AUC value and false-negative rate. None of the models were able to achieve AUC value ≥ 0.80 in a cohort of British patients with breast cancer.

Predicting the likelihood of additional lymph node metastasis in sentinel lymph node positive breast cancer: validation of the Memorial Sloan-Kettering Cancer Centre (MSKCC) nomogram

AIM

To identify important clinicopathological parameters that are most helpful in predicting additional non-sentinel lymph node (SLN) metastasis among patients with a positive SLN biopsy in the Singapore breast cancer population.

METHODS

A total of 1409 patients who underwent SLN biopsy were reviewed over a 5 year period from July 2004 to October 2009. A Singapore General Hospital (SGH) nomogram was developed from predictors in the Memorial Sloan-Kettering Cancer Centre (MSKCC) nomogram using 266 patients with primary invasive breast cancer and a positive SLN biopsy who subsequently had an axillary lymph node dissection. The SGH nomogram was calibrated using bootstrapped data, while the MSKCC nomogram was calibrated using SGH data. The performance of these two nomograms was compared with the calculation of the area under the receiver-operator characteristics curve and adequacy indices.

RESULTS

The MSKCC nomogram achieved an area under the curve (AUC) of 0.716 (range 0.653-0.779) in our study population, while the SGH nomogram, which used only three pathological parameters, lymphovascular invasion, number of positive and negative SLN biopsies, achieved an AUC of 0.750 (range 0.691-0.808). The SGH nomogram with a higher adequacy index (0.969) provided better estimates compared with the MSKCC nomogram (0.689).

CONCLUSIONS

The use of the MSKCC nomogram was validated in our local patient population. The SGH nomogram showed promise to be equally, if not, more predictive as a model in our own population, while using only three pathological parameters.

Prediction of non-sentinel lymph node metastasis in early breast cancer by assessing total tumoral load in the sentinel lymph node by molecular assay

INTRODUCTION

The one-step nucleic acid amplification (OSNA) is a molecular procedure that yields a semiquantitative result for detection of nodal metastasis. Size of metastasis in the sentinel lymph node (SLN) by conventional histology has been described as a predictive factor for additional axillary metastasis. The objective of this study is to quantify intraoperatively the total tumoral load (TTL) in the positive SLNs assessed by OSNA and to determine whether this TTL predicts non-SLN metastasis in patients with clinically node negative early stage breast cancer.

METHODS

306 patients with cT1-3N0 invasive breast cancer who had undergone intraoperative SLN evaluation by OSNA were included. TTL was defined as the addition of CK19 mRNA copies of each positive SLN (copies/μL).

RESULTS

TTL was a predictive factor of additional non-SLN metastasis in the complete axillary lymph node dissection (cALND) (OR, 1.67; 95% CI, 1.18-2.35). In the multivariate analysis, the TTL was a predictor of non-SLN metastasis in HR positive patients (OR, 1.69; 95% CI, 1.19-2.41). In our cohort of patients, with a TTL ≤1.2 × 10(5) copies/μL, there was a specificity of 85.3% and negative predictive value (NPV) of 80%. If we consider only the HR positive patients, with a TTL ≤5 × 10(5) copies/μL there was a specificity of 86.7% and NPV of 83.7%.

CONCLUSIONS

TTL assessed by OSNA assay predicts for additional non-SLN metastasis and this intraoperative tool can help guiding decisions on performing a cALND in breast cancer patients.

Causes of false-negative sentinel node biopsy in patients with breast cancer

Background

Sentinel lymph node (SLN) biopsy has replaced axillary lymph node dissection as the routine staging procedure in clinically node-negative breast cancer. False-negative SLN biopsy results in misclassification and may cause undertreatment of the disease. The aim of this study was to investigate whether serial sectioning of SLNs reveals metastases more frequently in patients with false-negative SLNs than in patients with true-negative SLNs.

Methods

This was a case–control study. Tissue blocks from patients with false-negative SLNs, defined as tumour-positive lymph nodes excised at completion axillary dissection or a subsequent axillary tumour recurrence, were reassessed by serial sectioning and immunohistochemical staining. For each false-negative node, two true-negative SLN biopsies were analysed. Tumour and node characteristics in patients with false-negative SLNs were compared with those in patients with a positive SLN by univariable and multivariable regression analysis.

Results

Undiagnosed SLN metastases were discovered in nine (18 per cent) of 50 patients in the false-negative group and in 12 (11.2 per cent) of 107 patients in the true-negative group (P = 0.245). The metastases were represented by isolated tumour cells in 14 of these 21 patients. The risk of a false-negative SLN was higher in patients with hormone receptor-negative (odds ratio (OR) 2.50, 95 per cent confidence interval 1.17 to 5.33) or multifocal tumours (OR 3.39, 1.71 to 6.71), or if only one SLN was identified (OR 3.57, 1.98 to 6.45).

Conclusion

SLN serial sectioning contributes to a higher rate of detection of SLN metastasis. The rate of upstaging of the tumour is similar in false- and true-negative groups of patients.

Molecular subtype classification is a determinant of non-sentinel lymph node metastasis in breast cancer patients with positive sentinel lymph nodes

Background

Previous studies suggested that the molecular subtypes were strongly associated with sentinel lymph node (SLN) status. The purpose of this study was to determine whether molecular subtype classification was associated with non-sentinel lymph nodes (NSLN) metastasis in patients with a positive SLN.

Methodology and Principal Findings

Between January 2001 and March 2011, a total of 130 patients with a positive SLN were recruited. All these patients underwent a complete axillary lymph node dissection. The univariate and multivariate analyses of NSLN metastasis were performed. In univariate and multivariate analyses, large tumor size, macrometastasis and high tumor grade were all significant risk factors of NSLN metastasis in patients with a positive SLN. In univariate analysis, luminal B subgroup showed higher rate of NSLN metastasis than other subgroup (P = 0.027). When other variables were adjusted in multivariate analysis, the molecular subtype classification was a determinant of NSLN metastasis. Relative to triple negative subgroup, both luminal A (P = 0.047) and luminal B (P = 0.010) subgroups showed a higher risk of NSLN metastasis. Otherwise, HER2 over-expression subgroup did not have a higher risk than triple negative subgroup (P = 0.183). The area under the curve (AUC) value was 0.8095 for the Cambridge model. When molecular subtype classification was added to the Cambridge model, the AUC value was 0.8475.

Conclusions

Except for other factors, molecular subtype classification was a determinant of NSLN metastasis in patients with a positive SLN. The predictive accuracy of mathematical models including molecular subtype should be determined in the future.

Factors predicting the non-sentinel lymph node involvement in breast cancer patients with sentinel lymph node metastases

OBJECTIVE

In a significant proportion of patients, the sentinel lymph node (SLN) is the only involved axillary node. The goal of the present study was to identify predictive factors associated with a positive SLN and with a positive non-SLN in patients in whom axillary lymph node dissection (ALND) was performed.

METHODS

Data was reviewed for patients with T1-2 invasive breast cancer who underwent SLN biopsy with or without axillary dissection in a single institution between July 2000 and May 2010. The SLNs were examined by serial sectioning and H&E staining, and by cytokeratin immunostaining in suspicious cases.

RESULTS

Of 332 patients with SLNB, 134 had SLN positivity, and 116 of them further underwent completion axillary dissection. Patients with T2 tumors (OR=3.2; 95% CI, 1.74-5.58), or tumors with lymphovascular invasion (OR=8.0; 95% CI, 4.44-14.27), or invasive ductal cancer (OR=2.92; 95% CI, 1.1-8.0) were more likely to have a positive SLN. In patients with ALND, the non-SLN involvement rates were 10%, 11.5% and 50% in patients with isolated tumor cells (ITC), micrometastasis and macrometastasis, respectively. Finding of ITC or micrometastasis in SLNs (OR=0.28; 95% CI, 0.08-0.99) or presence of extracapsular invasion (ECI) in SLN (OR=0.24; 95% CI, 0.09-0.67) were the predictive factors of not having a non-SLN metastasis in logistic regression analysis.

CONCLUSIONS

These findings suggest further axillary surgery can be best omitted in patients with micrometastasis while validation of nomograms including factors such as ECI are still needed to be studied in patients with macrometastasis.

Prediction of non-sentinel lymph node status in breast cancer patients with sentinel lymph node metastases: evaluation of the tenon score

INTRODUCTION

Current guidelines recommend completion axillary lymph node dissection (cALND) in case of a sentinel lymph node (SLN) metastasis larger than 0.2 mm. However, in 50%-65% of these patients, the non-SLNs contain no further metastases and cALND provides no benefit. Several nomograms and scoring systems have been suggested to predict the risk of metastases in non-SLNs. We have evaluated the Tenon score.

PATIENTS AND METHODS

In a retrospective review of the Swedish Sentinel Node Multicentre Cohort Study, risk factors for additional metastases were analysed in 869 SLN-positive patients who underwent cALND, using uni- and multivariate logistic regression models. A receiver operating characteristic (ROC) curve was drawn on the basis of the sensitivity and specificity of the Tenon score, and the area under the curve (AUC) was calculated.

RESULTS

Non-SLN metastases were identified in 270/869 (31.1%) patients. Tumour size and grade, SLN status and ratio between number of positive SLNs and total number of SLNs were significantly associated with non-SLN status in multivariate analyses. The area under the curve for the Tenon score was 0.65 (95% CI 0.61-0.69). In 102 patients with a primary tumour <2 cm, Elston grade 1-2 and SLN metastases ≤2 mm, the risk of non SLN metastasis was less than 10%.

CONCLUSION

The Tenon score performed inadequately in our material and we could, based on tumour and SLN characteristics, only define a very small group of patients in which negative non-sentinel nodes could be predicted.

Predictors of non-sentinel lymph node metastasis in breast cancer patients with positive sentinel lymph node (Pilot study)

BACKGROUND

Sentinel Lymph Node Biopsy (SLNB) procedure was found to be an accurate method of staging the axilla in patients with early stage breast cancer. The standard of care for breast cancer patients with positive SLN metastasis includes complete Axillary Lymph Node Dissection (ALND). However, in 40-70% of patients, the SLN is the only involved axillary node. Factors predicting non SLN metastasis should be identified in order to define subgroups of patients with positive SLN in whom the axilla may be staged by SLNB alone.

OBJECTIVES

To identify the factors predicting metastatic involvement of the non-SLNs in breast cancer patients having SLN metastasis.

PATIENTS AND METHODS

Data were collected and analyzed from 80 patients with early stage invasive breast cancer (T1, T2, N0, M0) who underwent SLNB at the Surgical Oncology Department, Kuwait Cancer Control Center (KCCC) between November 2004 and February 2009. SLNB was performed using a combined technique (radioactive colloid, and blue dye) in the majority of cases. In some cases, only one technique was used. Complete ALND was performed in the case of failure of SLN identification and in patients with positive SLN. Multiple variables (patient, tumor, and SLN characteristics) were tested as possible predictors of nonsentinel lymph node metastasis.

RESULTS

The mean age of patients at diagnosis was 46.6years. The median tumor size was 2cm. The SLN identification rate was 96.2% (77 out of 80 patients). The SLN was positive in 24 patients (31%), and half of these showed evidence of capsular invasion. The median number of SLNs removed was two. The median number of positive SLNs was one. The incidence of non-SLN metastasis associated with positive SLN was 50% (12 out of 24 patients). Lymphovascular invasion was found to be the only factor associated with non-SLN metastases. In addition, two trends were observed, though they did not reach the statistical significance: the first is that the majority of patients having capsular invasion of the SLN (8 out of 12 patients, 67%) had positive non-SLN metastasis, and the second is that the patients having more than one SLN metastasis were more likely to have non-SLN metastasis (4 out of 5, 80%).

CONCLUSION

In the current pilot study, only the lymphovascular invasion in the area of the primary tumor was found to be significantly related to the nonsentinel lymph node metastasis. There was a tendency toward higher incidence of nonsentinel lymph node metastasis associated with the number of positive SLN and capsular invasion of SLN, though this did not reach the statistical significance. This could be attributed to the small number of patients recruited. Further evaluation of the predictors of nonsentinel lymph node metastasis on a larger number of patients is required. The validation of these predictors in prospective studies may enable approximately half of early stage breast cancer patients with positive SLN to be staged with SLNB alone while avoiding the morbidity of unnecessary ALND.

Meta-analysis of predictive factors for non-sentinel lymph node metastases in breast cancer patients with a positive SLN

AIMS

A meta-analysis was performed to identify the clinicopathological variables most predictive of non-sentinel node (NSN) metastases when the sentinel node is positive.

METHODS

A Medline search was conducted that ultimately identified 56 candidate studies. Original data were abstracted from each study and used to calculate odds ratios. The random-effects model was used to combine odds ratios to determine the strength of the associations.

FINDINGS

The 8 individual characteristics found to be significantly associated with the highest likelihood (odds ratio >2) of NSN metastases are SLN metastases >2mm in size, extracapsular extension in the SLN, >1 positive SLN, ≤1 negative SLN, tumour size >2cm, ratio of positive sentinel nodes >50% and lymphovascular invasion in the primary tumour. The histological method of detection, which is associated with the size of metastases, had a correspondingly high odds ratio.

CONCLUSIONS

We identified 8 factors predictive of NSN metastases that should be recorded and evaluated routinely in SLN databases. These factors should be included in a predictive model that is generally applicable among different populations.

Validation of the S classification of sentinel lymph node and microanatomic location of sentinel lymph node metastases to predict additional lymph node involvement and overall survival in breast cancer patients

BACKGROUND

Most patients with a positive sentinel lymph node (SN) have no further metastases in the axillary lymph nodes and may therefore not benefit from axillary lymph node dissection. In patients with melanoma, evaluation of the centripetal depth of tumor invasion in the SN, also known as the S classification of SN, and microanatomic localization of SN metastases were shown to predict non-SN involvement. This phenomenon has been less extensively studied in breast cancer. We sought to validate the S classification and microanatomic location of SN metastases in breast cancer patients with regard to their predictive value for non-SN involvement and overall survival (OS).

METHODS

A total of 236 patients with positive SN followed by axillary lymph node dissection were reevaluated according to the S classification and the microanatomic location of SN (subcapsular, parenchymal, combined subcapsular and parenchymal, multifocal, extensive) metastases to predict the likelihood of non-SN metastases and OS.

RESULTS

S classification and the microanatomic location of SN metastases were significantly correlated with non-SN status (P < 0.001). Especially patients with a maximum depth of invasion ≤0.3 mm (stage I according to the S classification) and those with SN metastases only in subcapsular location had a low probability of further non-SN metastases (7.8 and 6.1%) and a good prognosis for OS.

CONCLUSIONS

S classification and microanatomic location of SN metastases predicts the likelihood of non-SN involvement. Especially patients with subcapsular or S stage I metastases have a low probability of non-SN metastases and a good prognosis for OS.

Predictive value of sonographic features of extranodal extension in axillary lymph nodes

OBJECTIVE

The purpose of this study was to assess the accuracy of 5 sonographic features in the prediction of extranodal extension (ENE) in axillary lymph nodes (ALNs) of patients with biopsy-proven breast cancer.

METHODS

A review of our institution's surgical and pathologic database was performed for patients with pathologically proven axillary ENE from October 1, 2003, to October 1, 2007. An equivalent number of patients without ENE were included. All patients had sonograms of ALNs available. A radiologist to whom the study was masked reviewed ALN images with specific attention to unclear margins, node matting, perinodal edema, and hilar effacement or replacement. Univariate and multivariate logistic regression analyses were used to obtain the sensitivity, specificity, and odds ratio (OR) for each feature.

RESULTS

Our review included a total of 131 patients (64 with ENE and 67 without ENE). The respective sensitivity and specificity estimates for each feature were as follows: node matting, 52% and 84%; perinodal edema, 34% and 87%; unclear margins, 64% and 75%; hilar replacement, 71% and 42%; and hilar effacement, 74% and 60%. Univariate analysis showed a statistically significant association between features and ENE with ORs as follows: matting, 5.4; perinodal edema, 3.4; unclear margins, 5.2; and hilar replacement, 4.3. Multivariate analysis showed that matting and unclear margins were independently associated with ENE.

CONCLUSIONS

The sonographic features of unclear margins, node matting, perinodal edema, and hilar replacement have a statistically significant association with ENE. The sonographic features of unclear margins, node matting, and perinodal edema predict ENE with high specificity.

Clinical importance of micrometastasis in sentinel lymph nodes

INTRODUCTION

We evaluated the incidence of micrometastasis and nonsentinel lymph node metastasis as well as local and axillary recurrence rates after level I-II axillary lymph node dissection.

MATERIALS AND METHODS

Patients (n=760) with early-stage breast cancer underwent sentinel lymph node biopsy, and 45 patients (6.0%) with micrometastasis (0.2-2.0mm) were included in this study. Data concerning tumor, patients' characteristics and adjuvant treatments were recorded.

RESULTS

The median age was 46 (26-67) years, median breast tumor size was 20 (1-50) mm, and median number of excised sentinel lymph nodes were 2 (1-5). All patients with micrometastasis underwent further level I-II axillary lymph node dissection. Eleven of 45 (24.4%) patients with micrometastasis in their sentinel lymph node biopsy had nonsentinel lymph node metastasis after an axillary lymph node dissection. There was no factor related to nonsentinel lymph node metastasis. Stage migration occurred in 4 of 45 patients (8.8%) due to the detection of micrometastases or macrometastases in nonsentinel lymph nodes.

DISCUSSION

The classical treatment after detection of micrometastasis in sentinel lymph nodes is further axillary dissection. However, nonrandomized, nonprospective studies with 4-5 years follow up showed 0.6% axillary recurrence without further axillary lymph node dissection, although we still need the results of randomized controlled studies.