Breast Cancer Subtype is Associated With Axillary Lymph Node Metastasis: A Retrospective Cohort Study

Disease extent according to baseline [18F]fluorodeoxyglucose PET/CT and molecular subtype: prediction of axillary treatment response after neoadjuvant systemic therapy for breast cancer

BACKGROUND

Axillary disease extent according to baseline [18F]fluorodeoxyglucose PET/CT combined with pathological axillary treatment response has been proposed to guide de-escalation of axillary treatment for clinically node-positive breast cancer patients treated with neoadjuvant systemic therapy. The aim of this study was to assess whether axillary disease extent according to baseline [18F]fluorodeoxyglucose PET/CT and breast cancer molecular subtype are predictors of axillary pCR.

METHODS

This study included clinically node-positive patients treated with neoadjuvant systemic therapy in the prospective Radioactive Iodine Seed placement in the Axilla with Sentinel lymph node biopsy ('RISAS') trial (NCT02800317) with baseline [18F]fluorodeoxyglucose PET/CT imaging available. The predictive value of axillary disease extent according to baseline [18F]fluorodeoxyglucose PET/CT and breast cancer molecular subtype to estimate axillary pCR was evaluated using logistic regression analysis. Discriminative ability is expressed using ORs with 95% confidence intervals.

RESULTS

Overall, 185 patients were included, with an axillary pCR rate of 29.7%. The axillary pCR rate for patients with limited versus advanced baseline axillary disease according to [18F]fluorodeoxyglucose PET/CT was 31.9% versus 26.1% respectively. Axillary disease extent was not a significant predictor of axillary pCR (OR 0.75 (95% c.i. 0.38 to 1.46) (P = 0.404)). There were significant differences in axillary pCR rates between breast cancer molecular subtypes. The lowest probability (7%) was found for hormone receptor+/human epidermal growth factor receptor 2- tumours. Using this category as a reference group, significantly increased ORs of 14.82 for hormone receptor+/human epidermal growth factor receptor 2+ tumours, 40 for hormone receptor-/human epidermal growth factor receptor 2+ tumours, and 6.91 for triple-negative tumours were found (P < 0.001).

CONCLUSION

Molecular subtype is a significant predictor of axillary pCR after neoadjuvant systemic therapy, whereas axillary disease extent according to baseline [18F]fluorodeoxyglucose PET/CT is not.

Alteration of the immune microenvironment in the axillary metastatic lymph nodes of luminal A breast cancer patients

BACKGROUND

The alteration of the immune microenvironment in the axillary metastatic lymph nodes of luminal A breast cancer patients is still unclear.

METHODS

Postsurgical tissues from the enrolled luminal A BCs were divided into five categories: primary BC lesion at stage N0 (PL1), primary BC lesion at stage N1 (PL2), negative axillary lymph node at stage N0 BC (LN1), negative axillary lymph node at stage N1 BC (LN2), and positive axillary lymph node at stage N1 BC (LN3). The frequencies of positive immune markers (CD4, CD8, PD1, PD-L1, T-cell immunoglobulin and mucin domain 3 (TIM3), and forkhead box protein 3 (Foxp3)) in the above tissues were quantified by AKOYA Opal Polaris 7 Color Manual IHC Detection Kit.

RESULTS

A total of 50 female patients with luminal A BC were enrolled in this study. Among these patients, 23 had stage N1 disease, and 27 had stage N0 disease. Compared with that in the PL2 subgroup, the frequency of PD-1-positive cells was significantly greater in the PL1 subgroup, whether at the stromal or intratumoral level (P value < 0.05). Both the frequency of CD8 + T cells in LN1 and that in LN2 were significantly greater than that in LN3 (P value < 0.05). The frequency of TIM3 + T cells in LN1 was significantly greater than that in PL1 (P value < 0.05). The frequency of CD8 + TIM3 + T cells was significantly greater in both the LN2 and LN3 groups than in the PL2 group (P value < 0.05). The frequency of CD4 + Foxp3 + T cells was significantly greater in LN1 than in PL1 (P value < 0.05), which was the same for both LN3 and PL2 (P value < 0.05).

CONCLUSION

Increased frequencies of CD8 + PD1+, CD8 + TIM3 + and CD4 + Foxp3 + T cells might inhibit the immune microenvironment of axillary metastatic lymph nodes in luminal A breast cancer patients and subsequently promote lymph node metastasis.

Evaluating Recurrence Risk in Patients Undergoing Breast-conserving Surgery Using E-cadherin Staining as a Biomarker

BACKGROUND/AIM

Following the National Comprehensive Cancer Network guidelines, radiotherapy is administered after breast-conserving surgery (BCS) in patients with more than four positive lymph nodes. Four positive lymph nodes are typically considered an indicator to assess disease spread and patient prognosis. However, the subjective counting of positive axillary lymph nodes underscores the need for biomarkers to improve diagnostic precision and reduce the risk of unnecessary treatments. Loss of E-cadherin expression is associated with cancer metastasis, but its potential as a predictive marker for cancer treatment remains uncertain. This study aimed to investigate the validity of E-cadherin as a reference for adjuvant radiotherapy in breast cancer patients with positive lymph nodes post-mastectomy.

MATERIALS AND METHODS

Immunohistochemistry was performed on 60 clinical tissue specimens to assess these implications.

RESULTS

Although no significant result was found in a single E-cadherin subgroup (low, medium, and high subgroups according to the X-tile algorithm), the proposed multivariate model, including the E-cadherin category, breast cancer subtype, and tumor size, yielded satisfactory recurrence risk estimation results for patients undergoing BCS. Patients with a low E-cadherin category, triple-negative breast cancers, and tumor size over 5 cm could have an increased risk of recurrence.

CONCLUSION

Our study proposed a multivariate model that serves as a candidate prognostic factor for recurrence-free survival in patients undergoing BCS and radiotherapy. Utilizing this model for patient stratification in high-risk diseases and as a standard for assessing postoperative intensified therapy can potentially improve patient outcomes.

Do HER2-Low Tumors Have a Distinct Clinicopathologic Phenotype?

BACKGROUND

Breast cancer subtypes, distinguished by hormone receptor (HR) and HER2 status, have different clinicopathologic features. With recognition of the clinical relevance of HER2-low, there is debate as to whether this is a distinct subtype. Our study aimed to determine whether HER2-low breast cancers have specific clinicopathologic features that differ from those of HER2-negative and HER2-positive cancers.

PATIENTS AND METHODS

A total of 11,072 patients undergoing upfront surgery from 1998 to 2010 were identified from a single-institution prospectively maintained database. HER2 status was classified by immunohistochemistry (IHC)/fluorescence in situ hybridization (FISH) as HER2 negative (41.2%), HER2 low (45%; IHC 1+ or 2+ with negative FISH), and HER2 positive (13.7%), and stratified by HR status. Univariate (UVA) and multivariable multinomial logistic regression analysis (MVA) were performed to determine associations among variables and subtypes.

RESULTS

Compared with HER2-negative tumors, HER2 low was associated with lymphovascular invasion [odds ratio (OR) 1.2, 95% confidence interval (CI) 1.06-1.36; p = 0.003], multifocality (OR 1.26, 95% CI 1.12-1.42; p < 0.001), nodal micrometastasis (OR 1.15, 95% CI 1.02-1.31; p = 0.024), and lower rates of ≥ 3 positive nodes (OR 0.77, 95% CI 0.66-0.90, p = 0.001). When stratified by HR expression, in both HR-positive and HR-negative tumors, age and multifocality were associated with HER2 low on UVA. On MVA, no variables were independently associated with both HR-negative and HR-positive/HER2-low tumors compared with HER2-negative tumors. In contrast, HER2-positive tumors, regardless of HR status, were associated with multifocality and an extensive intraductal component.

CONCLUSION

Clinicopathologic features of HER2-low tumors appear to be primarily related to HR status. Our findings do not support the characterization of HER2 low as a separate subtype.

Clinical study on the prediction of ALN metastasis based on intratumoral and peritumoral DCE-MRI radiomics and clinico-radiological characteristics in breast cancer

Objective

To investigate the value of predicting axillary lymph node (ALN) metastasis based on intratumoral and peritumoral dynamic contrast-enhanced MRI (DCE-MRI) radiomics and clinico-radiological characteristics in breast cancer.

Methods

A total of 473 breast cancer patients who underwent preoperative DCE-MRI from Jan 2017 to Dec 2020 were enrolled. These patients were randomly divided into training (n=378) and testing sets (n=95) at 8:2 ratio. Intratumoral regions (ITRs) of interest were manually delineated, and peritumoral regions of 3 mm (3 mmPTRs) were automatically obtained by morphologically dilating the ITR. Radiomics features were extracted, and ALN metastasis-related radiomics features were selected by the Mann-Whitney U test, Z score normalization, variance thresholding, K-best algorithm and least absolute shrinkage and selection operator (LASSO) algorithm. Clinico-radiological risk factors were selected by logistic regression and were also used to construct predictive models combined with radiomics features. Then, 5 models were constructed, including ITR, 3 mmPTR, ITR+3 mmPTR, clinico-radiological and combined (ITR+3 mmPTR+ clinico-radiological) models. The performance of models was assessed by sensitivity, specificity, accuracy, F1 score and area under the curve (AUC) of receiver operating characteristic (ROC), calibration curves and decision curve analysis (DCA).

Results

A total of 2264 radiomics features were extracted from each region of interest (ROI), 3 and 10 radiomics features were selected for the ITR and 3 mmPTR, respectively. 5 clinico-radiological risk factors were selected, including lesion size, human epidermal growth factor receptor 2 (HER2) expression, vascular cancer thrombus status, MR-reported ALN status, and time-signal intensity curve (TIC) type. In the testing set, the combined model showed the highest AUC (0.839), specificity (74.2%), accuracy (75.8%) and F1 Score (69.3%) among the 5 models. DCA showed that it had the greatest net clinical benefit compared to the other models.

Conclusion

The intra- and peritumoral radiomics models based on DCE-MRI could be used to predict ALN metastasis in breast cancer, especially for the combined model with clinico-radiological characteristics showing promising clinical application value.

Integrative analysis identifies two molecular and clinical subsets in Luminal B breast cancer

Comprehensive multiplatform analysis of Luminal B breast cancer (LBBC) specimens identifies two molecularly distinct, clinically relevant subtypes: Cluster A associated with cell cycle and metabolic signaling and Cluster B with predominant epithelial mesenchymal transition (EMT) and immune response pathways. Whole-exome sequencing identified significantly mutated genes including TP53, PIK3CA, ERBB2, and GATA3 with recurrent somatic mutations. Alterations in DNA methylation or transcriptomic regulation in genes (FN1, ESR1, CCND1, and YAP1) result in tumor microenvironment reprogramming. Integrated analysis revealed enriched biological pathways and unexplored druggable targets (cancer-testis antigens, metabolic enzymes, kinases, and transcription regulators). A systematic comparison between mRNA and protein displayed emerging expression patterns of key therapeutic targets (CD274, YAP1, AKT1, and CDH1). A potential ceRNA network was developed with a significantly different prognosis between the two subtypes. This integrated analysis reveals a complex molecular landscape of LBBC and provides the utility of targets and signaling pathways for precision medicine.

Predictors of nodal metastases in early stage HER2+ breast cancer: Deciding on treatment approach with neoadjuvant chemotherapy vs. upfront surgery

BACKGROUND

The purpose of this study is to evaluate preoperative predictors of nodal metastases in patients with early-stage, HER2-positive (HER2+) breast cancer.

METHODS

The SEER Database was queried to identify women with a first diagnosis of stage I-II (T1-T2) HER2-positive breast cancer treated with upfront surgery in 2018. Multivariable logistic regression was used to identify clinical characteristics independently associated with nodal involvement.

RESULTS

Overall, 3333 women with stage I-II HER2+ breast cancer met inclusion criteria and were included in the study. The median age at diagnosis was 59 years (IQR, 51-69 years). Most patients underwent breast-conserving surgery (60.9%), with a median of 3 (IQR 2-4) axillary lymph nodes removed. On final pathology, 762 (22.9%) of T1-T2 HER2+ patients were node positive; 2.7% pN0[i+], 3.7% pN1mi, 15.1% pN1, and 1.4% pN2. Women less than 40 years and those between 40 and 49 years showed the highest proportion of axillary lymph node metastasis, in 33.7% and 30.7% respectively, and declining with age (p < 0.001). Patients with triple-positive breast cancer had the highest rates of nodal involvement (24.8%), compared to 20.7% ER+/PR-/HER2+ and 19.6% of HER2-enriched patients (p = 0.006). On adjusted analysis, age, biologic subtype, tumour size, and type of surgery remained independent predictors of nodal involvement. On subgroup analysis, women under age 50 with T1c HER2-enriched or triple-positive breast cancer had a 33% and 35% incidence of nodal involvement, which declined with age.

CONCLUSIONS

The likelihood of pathologic nodal involvement in early-stage HER2+ breast cancer is contingent on age, ER/PR status, and tumour size.

Single cell profiling of primary and paired metastatic lymph node tumors in breast cancer patients

The microenvironment of lymph node metastasized tumors (LNMT) determines tumor progression and response to therapy, but a systematic study of LNMT is lacking. Here, we generate single-cell maps of primary tumors (PTs) and paired LNMTs in 8 breast cancer patients. We demonstrate that the activation, cytotoxicity, and proliferation of T cells are suppressed in LNMT compared with PT. CD4⁺CXCL13⁺ T cells in LNMT are more likely to differentiate into an exhausted state. Interestingly, LAMP3⁺ dendritic cells in LNMT display lower T cell priming and activating ability than in PT. Additionally, we identify a subtype of PLA2G2A⁺ cancer-associated fibroblasts enriched in HER2⁺ breast cancer patients that promotes immune infiltration. We also show that the antigen-presentation pathway is downregulated in malignant cells of the metastatic lymph node. Altogether, we characterize the microenvironment of LNMT and PT, which may shed light on the individualized therapeutic strategies for breast cancer patients with lymph node metastasis.

Survival of BRCA1/BRCA2-associated pT1 breast cancer patients, a cohort study

Purpose

Intensive screening in BRCA1/2 mutation carriers aims to improve breast cancer (BC) prognosis. Our aim is to clarify the prognostic impact of tumor size in BRCA mutation carriers with a pT1 BC, which is currently unclear. We are especially interested in differences between pT1a, pT1b, and pT1c regarding the prognosis of node-negative breast cancer, the effect of chemotherapy, and the prevalence of lymph node involvement.

Methods

For this study, BRCA1/2-associated BC patients were selected from a nationwide cohort. Primary outcomes were 10-year overall survival (OS) per pT1a-b-c group and the effect of chemotherapy on prognosis of node-negative BC, using Kaplan–Meier and Cox models. Finally, we evaluated lymph node involvement per pT1a-b-c group.

Results

963 women with pT1 BRCA1/2-associated BC diagnosed between 1990 and 2017 were included, of which 679 had pN0 BC. After a median follow-up of 10.5 years, 10-year OS in patients without chemotherapy was 77.1% in pT1cN0 and lower than for pT1aN0 (91.4%, p = 0.119) and pT1bN0 (90.8%, p = 0.024). OS was better with than without chemotherapy for pT1cN0 (91.6% vs. 77.1%, p = 0.001; hazard ratio (HR) 0.56, 95% confidence interval (CI): 0.21–1.48). Lymph node involvement was 24.9% in pT1c, 18.8% in pT1b, and 8.6% in pT1a.

Conclusion

Smaller tumor size is associated with better OS and less lymph node involvement in pT1 BRCA1/2-associated BC patients. The results suggest that early detection in BRCA1/2 mutation carriers of pT1a/b BC may reduce mortality and the need for systemic therapy.

Supplementary Information

The online version of this article contains supplementary material available (10.1007/s10549-022-06608-1.

Modeling Tumor: Lymphatic Interactions in Lymphatic Metastasis of Triple Negative Breast Cancer

Simple Summary

Lymphatic metastasis is a critical prognostic factor of breast cancer aggressiveness and patient survival. Since existing therapeutic approaches have shown limited efficacy, new strategies to identify effective therapeutic targets for reducing breast cancer lymphatic metastasis are needed. We have used novel culture chambers, designed and fabricated by our group, to develop 3D models in which we can study spat ial interactions between breast cancer cells and lymphatic cells as they occur in real-time. This approach provides information on the complex cell–cell interactions involved in lymphatic metastasis of breast cancers. Factors in the secretome of the lymphatic cells promote invasive outgrowths from 3D cultures of breast cancer cells, suggesting that targeting interactions between breast cancer cells and lymphatic cells could be a potential therapeutic approach for the prevention of lymphatic metastasis.

Abstract

Breast cancer frequently metastasizes to lymphatics and the presence of breast cancer cells in regional lymph nodes is an important prognostic factor. Delineating the mechanisms by which breast cancer cells disseminate and spatiotemporal aspects of interactions between breast cancer cells and lymphatics is needed to design new therapies to prevent lymphatic metastases. As triple-negative breast cancer (TNBC) has a high incidence of lymphatic metastasis, we used a three-dimensional (3D) coculture model of human TNBC cells and human microvascular lymphatic endothelial cells (LECs) to analyze TNBC:LEC interactions. Non-invasive analyses such as live-cell imaging in real-time and collection of conditioned media for secretomic analysis were facilitated by our novel microfluidic chambers. The volumes of 3D structures formed in TNBC:LEC cocultures are greater than that of 3D structures formed by either LEC or TNBC monocultures. Over 4 days of culture there is an increase in multicellular invasive outgrowths from TNBC spheroids and an association of TNBC spheroids with LEC networks. The increase in invasive phenotype also occurred when TNBC spheroids were cultured in LEC-conditioned media and in wells linked to ones containing LEC networks. Our results suggest that modeling spatiotemporal interactions between TNBC and LECs may reveal paracrine signaling that could be targeted to reduce lymphatic metastasis.

Role of mammogram and ultrasound imaging in predicting breast cancer subtypes in screening and symptomatic patients

BACKGROUND

Breast cancer (BC) radiogenomics, or correlation analysis of imaging features and BC molecular subtypes, can complement genetic analysis with less resource-intensive diagnostic methods to provide an early and accurate triage of BC. This is pertinent because BC is the most prevalent cancer amongst adult women, resulting in rising demands on public health resources.

AIM

To find combinations of mammogram and ultrasound imaging features that predict BC molecular subtypes in a sample of screening and symptomatic patients.

METHODS

This retrospective study evaluated 328 consecutive patients in 2017-2018 with histologically confirmed BC, of which 237 (72%) presented with symptoms and 91 (28%) were detected via a screening program. All the patients underwent mammography and ultrasound imaging prior to biopsy. The images were retrospectively read by two breast-imaging radiologists with 5-10 years of experience with no knowledge of the histology results to ensure statistical independence. To test the hypothesis that imaging features are correlated with tumor subtypes, univariate binomial and multinomial logistic regression models were performed. Our study also used the multivariate logistic regression (with and without interaction terms) to identify combinations of mammogram and ultrasound (US) imaging characteristics predictive of molecular subtypes.

RESULTS

The presence of circumscribed margins, posterior enhancement, and large size is correlated with triple-negative BC (TNBC), while high-risk microcalcifications and microlobulated margins is predictive of HER2-enriched cancers. Ductal carcinoma in situ is characterized by small size on ultrasound, absence of posterior acoustic features, and architectural distortion on mammogram, while luminal subtypes tend to be small, with spiculated margins and posterior acoustic shadowing (Luminal A type). These results are broadly consistent with findings from prior studies. In addition, we also find that US size signals a higher odds ratio for TNBC if presented during screening. As TNBC tends to display sonographic features such as circumscribed margins and posterior enhancement, resulting in visual similarity with benign common lesions, at the screening stage, size may be a useful factor in deciding whether to recommend a biopsy.

CONCLUSION

Several imaging features were shown to be independent variables predicting molecular subtypes of BC. Knowledge of such correlations could help clinicians stratify BC patients, possibly enabling earlier treatment or aiding in therapeutic decisions in countries where receptor testing is not readily available.

Correlation between Grading Histopathology and Sentinel Lymph Node Metastasis in Early Breast Cancer in University of Sumatera Utara Hospital

BACKGROUND: Breast cancer is a malignancy in breast tissue from the duct or lobar epithelium. American Joint Committee on Cancer has specified important prognostic factors such as primary tumor size, regional lymph node status, and distant metastasis. Axillary lymph node status has been one of the most reliable prognostic factors in early breast cancer in women. Axillary lymph node dissection is an old method to identify metastasis in axillary lymph nodes and started being replaced by sentinel lymph node biopsy (SLNB). SLNB has been introduced as a minimal invasive procedure, but in Indonesia, this procedure cannot be done due to technology limitation. Grading tumor is one of the predictor factors that can predict lymph node metastasis. This predictor factor has been associated with sentinel lymph node metastasis significantly. AIM: According to this, we conduct this study to analyze the correlation between grading histopathology in breast cancer with sentinel lymph node metastasis to lower false-negative rate in SLNB using methylene blue dye. MATERIALS AND METHODS: In this study, we included 51 patients that qualified using inclusion and exclusion criteria. Then, sentinel lymph node metastasis and grading histopathology data were retrieved from the patient’s medical record. This data are analyzed using SPSS with Chi-square test. RESULTS: The most type of breast cancer in this study is invasive ductal carcinoma was found in 40 patients (78.4%). There are 22 of 51 patients (51.6%) with metastasis to sentinel lymph node, have Grade 3 in histopathologic findings. CONCLUSIONS: The statistical evaluation showed that there is significant correlation between grading histopathology and SLNB with p = 0.001.

Metastatic Breast Cancer, Organotropism and Therapeutics: A Review

The final stage of breast cancer involves spreading breast cancer cells to the vital organs like the brain, liver lungs and bones in the process called metastasis. Once the target organ is overtaken by the metastatic breast cancer cells, its usual function is compromised causing organ dysfunction and death. Despite the significant research on breast cancer metastasis, it's still the main culprit of breast cancer-related deaths. Exploring the complex molecular pathways associated with the initiation and progression of breast cancer metastasis could lead to the discovery of more effective ways of treating the devastating phenomenon. The present review article highlights the recent advances to understand the complexity associated with breast cancer metastases, organotropism and therapeutic advances.

Patterns of supraclavicular area failure after mastectomy in breast cancer patients: implications for target volume delineation

Purpose

To characterize the pattern of post-mastectomy supraclavicular lymph node (LN) metastases in patients with breast cancer (BC) and to provide insights for individualized clinical target volume delineation for radiotherapy.

Methods

We retrospectively analyzed 88 patients with BC who developed post-mastectomy regional LN metastases. The affected regional LNs were categorized as the ipsilateral medial supraclavicular LN area (IMSC-LN), ipsilateral lateral supraclavicular LN area (ILSC-LN), ipsilateral infraclavicular LN area (IIC-LN), and ≥2 groups in the ipsilateral clavicular LN area (MMIC-LN). Clinical characteristics were included in a multivariate analysis to identify risk factors for clavicular LN metastases.

Results

The ILSC-LNs (68.2%) were the most common metastatic site. IMSC-LN metastases showed a significant association with estrogen-receptor (ER) negative status, left-sided BC, and positive axillary LNs. Tumor size ≥2.4 cm and Her2 type were predictors of ILSC-LN metastases. Additionally, tumor size ≥2.4 cm, and level I ipsilateral axillary metastases were associated with MMIC-LN metastasis.

Conclusion

ILSC-LN was the most frequently affected group of supraclavicular lymph nodes. ER-negative status, left-sided BC, tumor size, and positive ipsilateral axillary LNs are potentially associated with the pattern of supraclavicular LN metastatic involvement.

Differences in the Immune Response of the Nonmetastatic Axillary Lymph Nodes between Triple-Negative and Luminal A Breast Cancer Surrogate Subtypes

Breast cancer (BC) comprises four immunohistochemical surrogate subtypes of which triple-negative breast cancer (TNBC) has the highest risk of mortality. Axillary lymph nodes (ALNs) are the regions where BC cells first establish before distant metastasis, and the presence of tumor cells in the ALN causes an immune tolerance profile that contrasts with that of the nonmetastatic ALN (ALN^-). However, few studies have compared the immune components of the ALNs^- in BC subtypes. The present study aimed to determine whether differences between immune populations in the primary tumor and ALNs^- were associated with the luminal A or TNBC subtype. We evaluated a retrospective cohort of 144 patients using paraffin-embedded biopsies. The TNBC samples tended to have a higher histologic grade and proliferation index and had higher levels of immune markers compared with luminal A in primary tumors and ALNs^-. Two methods for validating the multivariate analysis found that histologic grade, intratumoral S100 dendritic cells, and CD8 T lymphocytes and CD57 natural killer cells in the ALNs^- were factors associated with TNBC, whereas CD83 dendritic cells in the ALNs^- were associated with the luminal A subtype. In conclusion, we found that intratumoral regions and ALNs^- of TNBC contained higher concentrations of markers related to immune tolerance than luminal A. This finding partially explains the worse prognosis of patients with TNBC.

Single-cell analysis reveals immune modulation and metabolic switch in tumor-draining lymph nodes

Lymph-node metastasis is a prognosis factor for poor clinical outcome of breast cancer patients. Currently, how breast cancer cells establish pre-metastatic niche in the tumor-draining lymph nodes (TDLNs) is still unclear. To address this question, we isolated heterogeneous cells including immune and stromal cells from naive lymph nodes (LNs) of the FVB/NJ mice and TDLNs of the MMTV-PyMT mice. Single-cell RNA sequencing was performed to investigate the transcriptome of the cells and various bioinformatics analyses were used to identify the altered pathways. Our results revealed several significant changes between naïve LNs and TDLNs. First, according to immunologic signature and pathway analysis, CD4+ and CD8 + T cells showed upregulated angiogenesis pathway genes and higher regulatory T (Treg)-associated genes while they demonstrated downregulation of interferon response and inflammatory response gene signatures, concurrently suggesting an immunosuppressive microenvironment in the TDLNs. Second, profiling of B cells showed down-regulation of marginal zone B lymphocytes in the TDLNs, which was validated by flow cytometric analysis. Third, we found the enhancement of oxidative phosphorylation pathway in the fibroblastic reticular cells (FRCs) of the MMTV-PyMT mice and the elevation of related genes including Prdx3, Ndufa4 and Uqcrb, suggesting massive ATP consumption and TCA cycle metabolism in the FRCs. Collectively, our results reveal the reprogramming of TDLNs during breast cancer progression at single-cell level in a spontaneous breast cancer model and suggest the changes in immune modulation and metabolic switch are key alterations in the preparation of pre-metastatic niche by breast cancer cells.

Studying Lymphatic Metastasis in Breast Cancer: Current Models, Strategies, and Clinical Perspectives

Breast cancer is the most commonly diagnosed cancer in women and the second most common cause of cancer-related deaths in the United States. Although early detection has significantly decreased breast cancer mortality, patients diagnosed with distant metastasis still have a very poor prognosis. The most common site that breast cancer spreads to are local lymph nodes. Therefore, the presence of lymph node metastasis remains one of most important prognostic factors in breast cancer patients. Given its significant clinical implications, increased efforts have been dedicated to better understand the molecular mechanism governing lymph node metastasis in breast cancer. The identification of lymphatic-specific biomarkers, including podoplanin and LYVE-1, has propelled the field of lymphatic metastasis forward. In addition, several animal models such as cell line-derived xenografts, patient-derived xenografts, and spontaneous tumor models have been developed to recreate the process of lymphatic metastasis. Moreover, the incorporation of various -omic platforms have provided further insight into the genetic drivers facilitating lymphatic metastasis, as well as potential biomarkers and therapeutic targets. Here, we highlight various models of lymphatic metastasis, their potential pitfalls, and other tools available to study lymphatic metastasis including imaging modalities and -omic studies.

Biomarker phenotyping drives clinical management in axillary sentinel node: A retrospective study on women with primary breast cancer in 2002

The current study examined if cancer biomarker phenotyping could predict the clinical/pathological status of axillary nodes in women with primary breast cancer. Primary breast cancers from 2002 were analyzed for tumor size, estrogen receptor (ER), progesterone receptor (PgR), Ki-67MIB expression and Her2/neu amplification. Relationships between the clinical and pathological status of the axilla and the biological subtypes classification were analyzed using univariate, multivariate and regression tree analysis. A total of 65% of women with axillary nodes clinically involved had complete axillary node dissection (ALND) while 705 women with clinically negative axillary underwent sentinel lymph node biopsy (SLNB), 18.5% of the latter had at least one pathologically SLNB involved node. Multivariate analysis revealed that the Luminal A subtype was significantly associated (OR 0.62; P<10^-9) with clinical negative axilla while HER2pos/not Luminal was associated with clinical positivity (OR 1.71; P<0.01). No significant association between biological subtypes and SLNB status was demonstrated. Regression tree analysis revealed that subgroups with significantly different probability of SLNB status were separated according to tumor size and PgR values. In conclusion, the current study demonstrated that biomarker breast cancer phenotyping is significantly associated with clinical status of axillary nodes but not with pathological involvement of nodes at SLNB. Regression tree analysis could represent a valid attempt to individualize some patients subgroups candidate to different surgical axilla approaches.

A Study Correlating the Tumor Site and Size with the Level of Axillary Lymph Node Involvement in Breast Cancer

BACKGROUND

Breast cancer is the leading cancer in women. The most common histologic type of breast cancer is infiltrating ductal carcinoma. The mainstay of the treatment of breast cancer is surgery when the tumor is localized, followed by chemotherapy as well as radiotherapy (when indicated) and in estrogen receptor and progesterone receptor positive tumors, adjuvant hormonal therapy.

AIMS AND OBJECTIVES

The aim of this study is to correlate tumor site and size with the level of axillary lymph node involvement (ALNI) in early and locally advanced breast cancer.

MATERIALS AND METHODS

This prospective and observational study was conducted on fifty female patients of carcinoma breast with early and locally advanced breast cancer.

RESULTS

The age distribution showed two peaks at 41-50 years and 51-60 years with 42 and 24 patients, respectively, in both the age groups. Preoperative lymph node positivity by ultrasonography matched with postoperative histopathological examination (HPE) report. Preoperative ultrasonographically determined tumor size was similar to the final histopathological T stage.

CONCLUSION

As size of tumor increases, there is an increase in ALNI which suggests that nodal metastasis is indicative of tumor chronology. Ultrasonography is a good tool to objectively measure tumor size and lymph node involvement preoperatively. Quadrant of involvement can emerge as a clinically useful prognostic cancer in breast cancer as there is a higher incidence of lymph node positivity with increasing size of the breast tumor and for tumors located at the upper outer quadrant of the breast.

The Role of Axillary Lymph Node Dissection in Tubular Carcinoma of the Breast: A Population Database Study

Background

The aim of this study was to investigate the role of axillary lymph node dissection on the outcome of patients with tubular carcinoma of the breast.

Material/Methods

Patients diagnosed with tubular carcinoma of the breast between 2000–2013 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Statistical analysis of the data was undertaken, including analysis of breast cancer-specific survival (BCSS).

Results

Of the 5,645 patients identified on the SEER database with tubular carcinoma of the breast, 5,032 (89.4%) patients had undergone axillary lymph node dissection, with significantly increased rates after 2002 compared with rates between 2000–2001 (p <0.001), which stabilized between 2002–2013 (p=0.330). Axillary lymph node metastases were present in 6.1% of all patients and in 5.3% of patients with a tumor size ≤2 cm. Lymph node-positive disease was associated with patient age ≤65 years, intermediate-grade or high-grade tumors, and tumor size >2.0 cm. Axillary lymph node dissection was an independent prognostic indicator. The 10-year BCSS was 97.3% and 96.6% in patients with and without axillary lymph node dissection, respectively (p=0.002). The number of removed lymph nodes was not related to breast cancer-specific survival.

Conclusions

In patients with tubular carcinoma of the breast, lymph node status was not associated with significant breast cancer-specific survival. However, axillary lymph node dissection may still be considered for patients with for tubular carcinoma of the breast even in patients with a small tumor size.

Does the subtype of breast cancer affect the diagnostic performance of axillary ultrasound for nodal staging in breast cancer patients?

INTRODUCTION

Imaging findings can be affected by histopathological characteristics, such as breast cancer subtypes. The aim was to determine whether the diagnostic performance, in particular negative predictive value (NPV), of axillary US differs per subtype of breast cancer.

METHODS

All patients diagnosed between 2008 and 2016 in our hospital with primary invasive breast cancer and an axillary US prior to axillary surgery were included. Histopathology of axillary surgery specimens served as gold standard. The NPV, sensitivity, specificity, positive predictive value (PPV) and accuracy of the axillary US were determined for the overall population and for each subtype (ER+/PR+HER2-,HER2+, triple negative tumors). The Chi-square test was used to determine the difference in diagnostic performance parameters between the subtypes.

RESULTS

A total of 1094 breast cancer patients were included. Of these, 35 were diagnosed with bilateral breast cancer, resulting in 1129 cancer cases. Most common subtype was ER+/PR+HER2- in 858 cases (76.0%), followed by 150 cases of HER2+ tumors (13.3%) and 121 cases of triple negative tumors (10.7%). Sensitivity, specificity and accuracy of axillary US did not significantly differ between the subtypes. There was a significant difference for NPV between triple negative tumors and HER2+ tumors (90.3% vs. 80.2%, p = 0.05) and between HER2+ and ER/PR+HER2- tumors (80.2% vs. 87.2%, p = 0.04).

CONCLUSION

There was no significant difference in the diagnostic performance of axillary US between the subtypes, except for NPV. This was highest in triple negative subtype and lowest in HER2+ tumors. This can be explained by the difference in prevalence of axillary lymph node metastases in our cohort.

Occult breast cancer may originate from ectopic breast tissue present in axillary lymph nodes

PURPOSE

Occult breast cancer (OBC) is classified as a carcinoma of unknown primary, and involves axillary lymphadenopathy and is histologically consistent with metastatic breast cancer. OBC has been conventionally considered as a metastatic lymph node lesion, the origin of which is an undetectable breast tumor. Therefore, OBC patients would usually have undergone axillary lymph node dissection, and mastectomy or whole breast radiotherapy (WBRT). However, majority of OBC reports have been based on cases that were diagnosed during a period when diagnostics was still relatively primitive, and when magnetic resonance imaging was not yet a standard preoperative assessment. Therefore, there have been many false negatives in the breast based on preoperative assessment.

METHODS

We herein hypothesize that the origin of OBC is ectopic breast tissue present in axillary lymph nodes (ALNs). If our hypothesis is true, mastectomy and WBRT may be unnecessary for OBC patients.

RESULTS

Our hypothesis is supported by several findings. First, advances in radiological imaging have suggested that a primary breast tumor is absent in OBC patients. Second, proliferative breast lesions arising from ectopic breast present in ALNs have been reported. Lastly, cellular subtypes in OBC based on immunohistochemistry are of various types including ordinary breast cancer and the prognosis is not worse than stage II breast cancer.

CONCLUSION

It is important to distinguish between "primary" OBC in ALNs and "metastatic" OBC from micro-primary breast tumor. Further studies are required to determine if omission of mastectomy and WBRT is acceptable.

The Association between Molecular Subtypes of Breast Cancer with Histological Grade and Lymph Node Metastases in Indonesian Woman

Objective: Breast carcinoma is a heterogeneous disease which is rich in diversity. Molecular subtypes of breast cancer, histological grade and lymph node metastases are strong prognostic and predictive factors. In Indonesia, only a limited number of studies have investigated the correlation between molecular subtypes with histological grade and lymph node metastases. Methods: We analyzed 247 invasive breast carcinoma cases from the Anatomic Pathology Installation of Dr. Sardjito General Hospital Yogyakarta between 2012-2015. The slides were stained for estrogen receptors (ER), progesterone receptors (PR), HER2, Ki-67 and CK5/6 for classification into breast cancer subtypes (BCS). Histological grade using the Nottingham system and lymph node status were obtained from anatomic pathology records. The association between histological grade and lymph node status with BCS was examined with Chi-square tests. Results: The immunohistochemical features of 247 cases of women with invasive breast carcinoma were examined. There were 102 (41.3%) patients with Luminal A, 34 (13.8%) patients with Luminal B, 48 (19.4%) patients with HER2-positive, and 63 (25.5%) patients with triple negative breast cancer (TNBC). There were 148 (59.9%) patients with negative lymph node status and 99 (40.1%) with positive status. Among 63 TNBC cases, 37 (58.7%) patients were positive for CK5/6 staining (basal-like). Statistically, there were significant differences between histological grade and subtypes (p=0.013). However, no significant differences were found for lymph node metastases (p=0.540). Conclusion: Among subtypes, Luminal A has the highest frequency, followed by TNBC, HER2-positive and Luminal B. Histological grade was associated with molecular subtypes of breast carcinoma in Yogyakarta. Grade I was associated with Luminal A, while Grade III was associated with Luminal B, HER2 and TNBC subtypes.

Organotropism: new insights into molecular mechanisms of breast cancer metastasis

Metastasis accounts for 90% of breast cancer mortality. Despite the significant progress made over the past decade in cancer medicine our understanding of metastasis remains limited, therefore preventing and targeting metastasis is not yet possible. Breast cancer cells preferentially metastasize to specific organs, known as “organotropic metastasis”, which is regulated by subtypes of breast cancer, host organ microenvironment, and cancer cells-organ interactions. The cross-talk between cancer cells and host organs facilitates the formation of the premetastatic niche and is augmented by factors released from cancer cells prior to the cancer cells’ arrival at the host organ. Moreover, host microenvironment and specific organ structure influence metastatic niche formation and interactions between cancer cells and local resident cells, regulating the survival of cancer cells and formation of metastatic lesions. Understanding the molecular mechanisms of organotropic metastasis is essential for biomarker-based prediction and prognosis, development of innovative therapeutic strategy, and eventual improvement of patient outcomes. In this review, we summarize the molecular mechanisms of breast cancer organotropic metastasis by focusing on tumor cell molecular alterations, stemness features, and cross-talk with the host environment. In addition, we also update some new progresses on our understanding about genetic and epigenetic alterations, exosomes, microRNAs, circulating tumor cells and immune response in breast cancer organotropic metastasis.

Predictive Value of 18F-FDG PET/CT for Axillary Lymph Node Metastasis in Invasive Ductal Breast Cancer

BACKGROUND

This study assessed whether primary tumor maximum standardized uptake value (pSUV_max) measured by ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) could improve the prediction of axillary lymph node (ALN) metastasis in invasive ductal breast cancer (IDC).

METHODS

In this study, 128 IDC patients who underwent pretreatment ¹⁸F-FDG PET/CT and surgical resection of primary tumor with sentinel lymph node biopsy, ALN dissection, or both were analyzed. All the patients were classified as five molecular subtypes. The optimal cutoff values of pSUVmax for all the patients and each molecular subtype for the prediction of ALN metastasis were determined using receiver operating characteristic (ROC) analysis. Furthermore, the prognostic accuracy of ALN metastasis was assessed using c-statistics.

RESULTS

The findings showed ALN metastasis in 52 patients (40.6%). The ¹⁸F-FDG PET/CT procedure had a sensitivity of 48.1% and a specificity of 94.7% for ALN metastasis. In the ROC analysis of pSUVmax for ALN metastasis, the optimal cutoff value was 3.9 for all the patients, 2.8 for the luminal A subtype, 3.3 for the luminal B (human epidermal growth factor receptor 2 [HER2]-negative) subtype, 5.3 for the luminal B (HER2-positive) subtype, 12.7 for the HER2-positive subtype, and 11.5 for the triple-negative subtype. A predictive ALN metastasis model using nodal ¹⁸F-FDG uptake finding gave a c-statistic of 0.714, and a model combination of nodal ¹⁸F-FDG uptake finding with pSUV_max of all the patients gave a c-statistic of 0.736 (P = 0.3926). However, the combination of nodal the ¹⁸F-FDG uptake finding with the pSUV_max of each molecular subtype gave a c-statistic of 0.791 (P = 0.0047).

CONCLUSIONS

Combining the pSUV_max of each molecular subtype with the nodal ¹⁸F-FDG uptake finding can improve the prediction of ALN metastasis in IDC.

HER2 expression is a strong independent predictor of nodal metastasis in breast cancer

Identification of metastatic potential of breast cancer cells is necessary for proper management of this disease. This work aimed to estimate likelihood of axillary lymph node (ALN) involvement in breast cancer patients based on human epidermal growth factor receptor 2 (HER2) expression. Primary tumors of 317 breast cancer patients were evaluated for estrogen receptor (ER), progesterone receptor (PR) and HER2 expression by immunohistochemistry. The validity of these molecules to predict ALN metastasis was measured statistically and compared to predictive effect of other clinicopathological parameters. ER, PR and HER2 expression was detected in 75.7%, 73.2% and 19.9% of tumors, respectively. Although increased tumor size and grade, ER and PR negativity and HER2 positivity were strong indicators of ALN metastasis on univariate analyses, only tumor size and HER2 expression were independent predictors of ALN involvement on multivariate analysis. ROC curve showed a strong validity of the model using these two parameters to predict ALN status (AUC 0.86; p<0001). HER2-rich, luminal B and triple negative tumors had 6.87, 6.32 and 3.58 times increased risk of metastasis compared to luminal A tumors; respectively. HER2 expression in pT1 and pT2 tumors raised the risk of ALN metastasis by 7.7 and 7.6 times, respectively and grade 1 and 2 tumors that expressed HER2 were 16.0 and 7.8 times more likely to have ALN metastasis, respectively. To conclude, HER2 expression is associated with a significant rise of metastatic potential of breast cancer cells and could be a strong indicator of regional and distant metastasis of breast cancer.

Comparison of clinicopathological characteristics of lymph node positive and lymph node negative breast cancer

OBJECTIVE

To record various clinicopathological characteristics of breast cancer (BC) in our population and to find an association between these characteristics and axillary nodal metastasis.

METHODS

This cross-sectional study included 150 BC patients from two tertiary care centers in Karachi from 15(th) February, 2013 to 31(st) March, 2015. Frequencies, percentages, and odds ratio were estimated to find out an association between various clinicopathological characteristics and lymph node status using SPSS version 20.

RESULTS

Approximately 75.4% patients had axillary lymph node metastasis ('1-3' LN = 34.4% and '>3' LN = 44%). Menopausal status (p <0.013), tumor grades ('II' p <0.03; 'III' p <0.01), and stages ('III' p <0.002; 'IV' p <0.0001), tumor sizes ('T2' p <0.014; 'T3' p <0.002), perineural invasion (PNI) (p <0.007), lymphovascular invasion (LVI) (p <0.0001), and skin and nipple invasion (p <0.024) were significant predictors for '>3' LN metastasis. Association of these variables with '1-3' LN involvement was insignificant.

CONCLUSION

Clinical spectrum of BC remains unchanged in 2016 with most of the patients presenting with high-grade, late-stage advanced disease. Moreover, clinicopathological variables, especially primary tumor size, tumor stage and lymphovascular invasion were significant predictors of >3 lymph node metastasis with high accuracy.