Inverse relationship between Ki67 and survival in early luminal breast cancer: confirmation in a multivariate analysis

The Role of Ki-67 in HR+/HER2- Breast Cancer: A Real-World Study of 956 Patients

Objective

This study determined the cut-off value of Ki-67 expression and discussed the interaction between Ki-67 and histological grade, further explored the prognostic role of Ki-67 in hormone receptor-positive and human epidermal growth factor receptor 2 negative (HR+/HER2-) breast cancer;.

Materials and Methods

We assessed the Ki-67 expression of 956 patients with HR+/HER2 breast cancer diagnosed in the General Hospital of Ningxia Medical University from 2015 to 2019 by immunohistochemistry (IHC), The disease-free survival (DFS) was defined as the time from postoperative to the first local recurrence, distant metastasis or death of the disease. The follow-up by means of inpatient or outpatient medical records and telephone.

Results

22.5% was used as the cut-off for low/high Ki-67 expression in HR+/HER2- breast cancer. Compared with the value of 14%, which is commonly used in clinic at present, the consistency of the two values is moderate (Kappa = 0.484, P<0.001). The expression of Ki-67 was increased with the grade. (Median: G1:10%; G2:20%; G3:40%. Mean: G1:13%; G2:23%; G3:39%, P <0.001). Survival analysis was based on all patients for a median of 51 months (24-89 months), 63 cases had recurrence or metastasis during the follow-up, which 21 cases had low expression of Ki-67 and 42 cases had high expression. The patients with Ki-67 ≥ 22.5% had a 2.969 higher risk of early recurrence and metastasis than the patients with Ki-67 < 22.5%. There were 4 cases of local recurrence, 7 cases of regional lymph node metastasis, and 52 cases of distant metastasis in all patients, the common distant metastases were bone, liver, and lung, and rare metastases were adrenal gland, bone marrow, and pericardium.

Conclusion

In HR+/HER2- breast cancer, patients with Ki-67 > 22.5% have a worse prognosis and are more likely to have early recurrence and metastasis.

Molecular, Cellular, and Technical Aspects of Breast Cancer Cell Lines as a Foundational Tool in Cancer Research

Breast cancer comprises about 30% of all new female cancers each year and is the most common malignant cancer in women in the United States. Breast cancer cell lines have been harnessed for many years as a foundation for in vitro analytic studies to understand the use of cancer prevention and therapy. There has yet to be a compilation of works to analyze the pitfalls, novel discoveries, and essential techniques for breast cancer cell line studies in a scientific context. In this article, we review the history of breast cancer cell lines and their origins, as well as analyze the molecular pathways that pharmaceutical drugs apply to breast cancer cell lines in vitro and in vivo. Controversies regarding the origins of certain breast cancer cell lines, the benefits of utilizing Patient-Derived Xenograft (PDX) versus Cell-Derived Xenograft (CDX), and 2D versus 3D cell culturing techniques will be analyzed. Novel outcomes from epigenetic discovery with dietary compound usage are also discussed. This review is intended to create a foundational tool that will aid investigators when choosing a breast cancer cell line to use in multiple expanding areas such as epigenetic discovery, xenograft experimentation, and cancer prevention, among other areas.

Association of Ki-67 Change Pattern After Core Needle Biopsy and Prognosis in HR+/HER2− Early Breast Cancer Patients

Background

To investigate the association of Ki-67 change pattern after core needle biopsy (CNB) and prognosis in HR+/HER2− early breast cancer patients.

Method

Eligible patients were categorized into three groups: Low group, Elevation group, and High group. Chi-square test and logistic regression analysis were used to compare the clinic-pathological characteristics. Kaplan–Meier method was used to estimate the rates of recurrence-free interval (RFI) and breast cancer-specific survival (BCSS), which were compared via the Log-rank test. Cox proportional hazard analysis was performed to investigate independent prognostic factors.

Results

A total of 2,858 patients were included: 1,179 (41.3%), 482 (16.9%), and 1,197 (41.8%) patients were classified into the low, elevation, and high groups, respectively. Age, tumor size, histological grade, lymph-vascular invasion (LVI), and ER level status were associated with Ki-67 change pattern after CNB. With a median follow-up of 53.6 months, the estimated 5-year RFI rates for the low group, elevation, and high groups were 96.4%, 95.3% and 90.9%, respectively (P < 0.001). And 5-year BCSS rates were 99.3%, 98.3% and 96.8%, respectively (P = 0.001). Compared with patients in the low group, patients in the high group had significantly worse RFI (hazard ratio [HR] 1.71, 95% confidence interval [CI] 1.16–2.54) in multivariate analysis.

Conclusions

Ki-67 change after CNB was associated with prognosis in HR+/HER2− early breast cancer. Patients with Ki-67 high or elevation after CNB had an inferior disease outcome, indicating the necessity of re-evaluating Ki-67 on surgical specimens after CNB.

Visual and digital assessment of Ki-67 in breast cancer tissue - a comparison of methods

Background

In breast cancer (BC) Ki-67 cut-off levels, counting methods and inter- and intraobserver variation are still unresolved. To reduce inter-laboratory differences, it has been proposed that cut-off levels for Ki-67 should be determined based on the in-house median of 500 counted tumour cell nuclei. Digital image analysis (DIA) has been proposed as a means to standardize assessment of Ki-67 staining in tumour tissue. In this study we compared digital and visual assessment (VA) of Ki-67 protein expression levels in full-face sections from a consecutive series of BCs. The aim was to identify the number of tumour cells necessary to count in order to reflect the growth potential of a given tumour in both methods, as measured by tumour grade, mitotic count and patient outcome.

Methods

A series of whole sections from 248 invasive carcinomas of no special type were immunohistochemically stained for Ki-67 and then assessed by VA and DIA. Five 100-cell increments were counted in hot spot areas using both VA and DIA. The median numbers of Ki-67 positive tumour cells were used to calculate cut-off levels for Low, Intermediate and High Ki-67 protein expression in both methods.

Results

We found that the percentage of Ki-67 positive tumour cells was higher in DIA compared to VA (medians after 500 tumour cells counted were 22.3% for VA and 30% for DIA). While the median Ki-67% values remained largely unchanged across the 100-cell increments for VA, median values were highest in the first 1-200 cells counted using DIA. We also found that the DIA100 High group identified the largest proportion of histopathological grade 3 tumours 70/101 (69.3%).

Conclusions

We show that assessment of Ki-67 in breast tumours using DIA identifies a greater proportion of cases with high Ki-67 levels compared to VA of the same tumours. Furthermore, we show that diagnostic cut-off levels should be calibrated appropriately on the introduction of new methodology.

Clinicopathological analysis of invasive cribriform carcinoma of the breast, with review of the literature

Invasive cribriform carcinoma (ICC) is a rare type of a primary breast carcinoma. It is subdivided into two groups as pure and mixed types. There are limited studies comparing the pure and mixed ICC at present. We aim to investigate the clinicopathological, radiological, prognostic features, and survival outcomes of two types with reviewing the published literature. 16 pure ICC and 26 mixed ICC cases were evaluated. The population consisted of 41 female and 1 male patients. The only male patient was a pure ICC case. The median age was for pure and mixed type, 46.5 and 54 years, respectively. All ICCs were ER positive. All ICCs except one mixed ICC, were positive for PR. Only one mixed ICC was accepted HER2 positive (3+). Pure ICCs showed more favorable features than mixed ICCs such as lesser axillary lymph node involvement, lower grade, and proliferation index. Twenty-five patients had one of the following imaging methods; ultrasonography (US), mammography (MG), and magnetic resonance imaging (MRI). Irregular shape, hypoechogenicity, and spiculated margins were the most common US findings. Similarly, irregular shape+spiculated margin is the most common MG findings. The median follow-up time for pure and mixed ICC was 88 and 56.5 months, respectively. One mixed ICC case developed bone metastasis. One death occurred in each group. Reasons of death were unknown. The 5-year OS for both ICC groups was 100%. 10-year OS for pure and mixed ICCs was 100% and 90%, respectively. 5-year DFS was 100% for pure ICC, and 94% for mixed ICC.

Oral Selective Estrogen Receptor Degraders (SERDs) as a Novel Breast Cancer Therapy: Present and Future from a Clinical Perspective

Estrogen receptor-positive (ER+) is the most common subtype of breast cancer. Endocrine therapy is the fundamental treatment against this entity, by directly or indirectly modifying estrogen production. Recent advances in novel compounds, such as cyclin-dependent kinase 4/6 inhibitors (CDK4/6i), or phosphoinositide 3-kinase (PI3K) inhibitors have improved progression-free survival and overall survival in these patients. However, some patients still develop endocrine resistance after or during endocrine treatment. Different underlying mechanisms have been identified as responsible for endocrine treatment resistance, where ESR1 gene mutations are one of the most studied, outstanding from others such as somatic alterations, microenvironment involvement and epigenetic changes. In this scenario, selective estrogen receptor degraders/downregulators (SERD) are one of the weapons currently in research and development against aromatase inhibitor- or tamoxifen-resistance. The first SERD to be developed and approved for ER+ breast cancer was fulvestrant, demonstrating also interesting activity in ESR1 mutated patients in the second line treatment setting. Recent investigational advances have allowed the development of new oral bioavailable SERDs. This review describes the evolution and ongoing studies in SERDs and new molecules against ER, with the hope that these novel drugs may improve our patients’ future landscape.

Mastectomy alone for pT1-2 pN0-1 breast cancer patients: when postmastectomy radiotherapy is indicated

PURPOSE

To assess outcome of breast cancer (BC) stages pT1-2 N0-1 after mastectomy alone and to identify prognostic factors calling for the need of postmastectomy radiotherapy.

METHODS

Patients who were not eligible for breast conserving surgery (BCS) were operated on with mastectomy between 1998 and 2008. Locoregional (LRR), distant (DM) control and breast cancer specific survival (BCSS) were retrospectively evaluated. Cumulative incidence (CI) of events was estimated according to Kalbfleisch and Prentice while Gray's test tested difference. Kaplan-Meier method for survival and Cox proportional hazards model for univariable and multivariable analysis were used. A matched pair analysis between mastectomy alone and BCS plus whole breast irradiation (WBI), using the propensity score method, was performed.

RESULTS

1281 pT1-2 N0 and 1081 pT1-2 N1 were identified. Median follow-up was 8.2 years (9.2 years for survival). Overall, LRR rate was low for both N0 and N1 subgroups (10-year CI, 8.8% and 10.9%, respectively). Young age, lymphovascular invasion and Ki-67 ≥ 20% were proved to be statistically significant prognostic factors at multivariable analysis. The combination of ≥ 2 risk factors increased LRR rate to ≥ 15%. Risk factors combination weighed on LRR rate more than nodal status itself. DM rate doubled moving from negative to positive nodal status (10-year CI 10.5% versus 20.3%, respectively). BCSS remained high in both N0 and N1 subgroups (10-year CI 92.4% versus 84.5%, respectively). Remarkably, all the molecular subtypes except Luminal A significantly affected DM and BCSS both in the N0 and N1 subgroups. Nodes number significantly impacted on DM and BCSS but not on locoregional control. In the matched pair analysis, WBI decreased nodal recurrence rate and improved distant control, without affecting survival.

CONCLUSIONS

Selected patients, namely those with at least two additional risk factors, presented high enough LRR risk to support the use of postmastectomy radiotherapy in both N0 and N1 subgroups. Moreover, the observation that radiotherapy may provide benefits that go beyond local control deserves to be further investigated.

Association between the methylation status of PCDH17 and the efficacy of neoadjuvant chemotherapy in triple-negative breast cancer

The present study aimed to assess whether the methylation status of the protocadherin 17 gene (PCDH17) in triple-negative breast cancer (TNBC) tissues was associated with the efficacy of neoadjuvant chemotherapy (NAC). The present study included 280 patients diagnosed with TNBC using core needle biopsy. Tumor pathological diagnosis was determined via hematoxylin and eosin staining. Immunohistochemical staining was used to determine estrogen receptor, progesterone receptor, human epidermal growth factor receptor-2 and Ki-67 status. PCDH17 methylation status was analyzed using methylation-specific PCR. χ² tests were performed to analyze differences between PCDH17 methylation status and TNBC clinicopathological features. Univariate and multivariate logistic regressions were used to analyze whether PCDH17 methylation status predicted a curative effect of NAC. The multivariate analysis included factors with P<0.2 from the univariate analysis and those that were clinically associated with NAC. A total of 228 patients were positive for PCDH17 methylation, while the remainder 52 were negative. Additionally, 107 patients achieved pathological complete response (pCR) after NAC. The pCR rate was 67.3% among the 52 patients negative for PCDH17 methylation and 31.6% among the 228 patients positive for PCDH17 methylation. Patients who were negative for PCDH17 methylation and had high Ki67 expression exhibited significantly higher pCR rates than their counterparts. The present results demonstrate that PCDH17 methylation status may predict the response to NAC in patients with TNBC. Therefore, this epigenetic characteristic may serve as an indicator of treatment efficacy.

Experimental Breast Cancer Models: Preclinical Imaging Perspective

BACKGROUND

Breast cancer is the leading cause of cancer in women. 13% of breast cancer patients are at a distant stage and mortality is due to metastases rather than primary disease. The unique genetic structure and natural process of breast cancer make it a very suitable area for targeted therapies. Experimental tumor models are validated methods to examine the pathogenesis of cancer, the onset of the neoplastic process and progression.

OBJECTIVE

This study aims to review the current literature on experimental breast cancer models and to bring a new perspective to the use of these models in teranostic preclinical studies in terms of the imaging.

METHODS

Search for relevant literature from academic databases using keywords (Breast cancer, theranostic, preclinical imaging, tumor models, animal study, and tailored therapy) was conducted. The full text of the articles was reached and reviewed. Current scientific data has been reevaluated and compiled according to subtitles.

RESULTS AND CONCLUSION

The development of animal models for breast cancer research has been done in the last century. Imaging methods used in breast cancer are used for tumor localization, quantification of tumor mass, imaging of genes and proteins, evaluation of tumor microenvironment, evaluation of tumor cell proliferation and metabolism and treatment response evaluation. Since human breast cancer is a heterogeneous group of diseases in terms of genetics and phenotype; it is not possible for a single model to adequately address all aspects of breast cancer biology. Considering that each model has advantages and disadvantages, the most suitable model should be chosen to verify the thesis of the study.

Diagnostic value of molybdenum target combined with DCE-MRI in different types of breast cancer

This study compared the diagnostic value of molybdenum target and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in different types of breast cancer. A retrospective analysis was performed on 120 female patients with breast cancer admitted to The First Affiliated Hospital of Zhengzhou University from February 2015 to October 2017. All of them underwent DCE-MRI and molybdenum target examination. Postoperatively, the pathological tissues were examined to determine their molecular typing. The sensitivity and diagnostic coincidence rates of Luminal-B breast cancer with different molecular types diagnosed by molybdenum target combined with DCE-MRI were significantly higher than those of molybdenum target or DCE-MRI alone. There were no statistical differences in sensitivity and diagnostic coincidence rates of breast cancer with different molecular types diagnosed by molybdenum target or DCE-MRI alone between the two groups (P>0.05). Molybdenum target combined with DCE-MRI in the diagnosis of different molecular types of breast cancer is better than the single imaging screening, which is of great clinical significance in the development of individualized comprehensive treatment for breast cancer patients and worthy of wide promotion in clinical practice.

Neoadjuvant endocrine therapy: A potential strategy for ER-positive breast cancer

A potential strategy for patients with estrogen receptor (ER)-positive breast cancer is necessary to replace neoadjuvant chemotherapy which has limited benefit. Neoadjuvant endocrine therapy (NAE) has been indicated to be a favorable alternate approach to downstage large or locally advanced breast cancer in ER-positive, human epidermal growth factor receptor 2 (HER2)-negative (ER+/HER2-) patients, especially postmenopausal women. Previous studies have demonstrated the efficacy of various endocrine agents in NAE. Aromatase inhibitors (AIs) have proven superiority over tamoxifen as a suitable choice to optimize treatment efficacy. Fulvestrant was recently reported as an effective agent, similar to AIs. Furthermore, the addition of targeted agents exerts synergistic antiproliferative effects with endocrine agents and rapidly improves response rates in both endocrine sensitive and resistant tumors. The neoadjuvant platform provides a unique opportunity to define the appropriate strategy and address the mechanisms of endocrine resistance. In addition, the predictive value of biomarkers and genomic assays in NAE is under investigation to evaluate individual effects and validate biomarker-based strategies. In this review, we discuss the most relevant evidence on the potential of NAE for ER+ breast cancer. The current understanding also offers new insights into the identification of the optimal settings and valuable predictive tools of NAE to guide clinical treatment decisions and achieve beneficial therapeutic effects.

A pilot study of low-dose CT perfusion imaging (LDCTPI) technology in patients with triple-negative breast cancer

PURPOSE

To investigate associations between the clinicopathologic features and CT perfusion parameters of triple-negative breast cancer (TNBC) and non-TNBC using low-dose computed tomography perfusion imaging (LDCTPI), and to find potential clinical applications in the prognosis assessment of TNBC.

MATERIALS AND METHODS

A total of 60 patients with breast cancer confirmed by pathological examination were studied prospectively using LDCTPI on a 64-slice spiral CT scanner. The acquired volume data were used for calculations, mapping, and analysis by using a tumor perfusion protocol in the CT perfusion software package to measure 2 parameters namely, blood flow (BF), and permeability surface (PS) area product. Patients were grouped into TNBC (n = 27) and non-TNBC (n = 33) subtypes. Associations between these two subtypes and clinicopathologic characteristics were evaluated by both univariate and multivariate logistic regression. CT perfusion parameters values were compared for clinicopathologic characteristics using independent 2-sample t test.

RESULTS

TNBC displayed higher CT perfusion parameters values (BF: 57.56±10.94 vs 52.70±7.79 mL/100 g/min, p = 0.006; PS: 38.98±9.46 vs 33.39±8.07 mL/100 g/min, p = 0.001) than non-TNBC. In addition, breast cancer with poorly histologic grade or positive Ki-67 expression showed higher BF and PS values than those with well and moderately histologic grade or negative Ki-67 expression (p < 0.05). TNBC had poorer histologic grade (P = 0.032) and higher Ki-67 expression (P = 0.013) than non-TNBC.

CONCLUSION

LDCTPI is a functional imaging technology from the perspective of hemodynamics with potential of clinical applications. The BF and PS values were higher in TNBC patient group than non-TNBC group. TNBC patients also have poorer clinicopathologic outcome.