One-Year Neoadjuvant Endocrine Therapy in Breast Cancer

The immune microenvironment characterisation and dynamics in hormone receptor-positive breast cancer before and after neoadjuvant endocrine therapy

BACKGROUND

Oestrogen receptor positive (ER+)/HER-2 negative breast cancer (BC) is considered to be an immunologically cold tumour compared to triple negative breast cancer. Therefore, the tumour microenvironment (TME) of ER+/HER-2 negative BC is understudied. The aim of this project is to investigate the TME and the immune response during neoadjuvant endocrine therapy (NET) and to correlate this with the treatment response in a real life setting.

METHODS

Expression of immune checkpoint receptors and immune cells was examined immunohistochemically, pre- and post-NET in a cohort of 56 ER+/HER-2 negative BC patients. They were treated with tamoxifen (n = 16), an aromatase inhibitor (n = 40) or a combination of an aromatase inhibitor with a PI3K inhibitor (n = 11) for a median duration of 6 months (range 1-32 months). Immunohistochemical staining with monoclonal antibodies for PDL-1, PD-1, TIM-3, LAG-3, CTLA-4, CD4, CD68 and FOXP3 were performed. All staining procedures were done according to validated protocols, and scoring was done by a pathologist specialized in breast cancer. Positivity was defined as staining >1% on TILs. Response to NET was evaluated according to tumour size change on imaging and Ki-67 change.

RESULTS

The median age was 61.02 (37-90) years. Diameter of tumour size decreased with a mean of 8.1 mm (-16 mm to 45 mm) (p < 0.001) during NET and the value of Ki-67 value decreased with a median of 9 after NET (p < 0.001). An increase in PD-L1 expression after NET showed a trend towards significant (p = 0.088) and CD-4+ T cells significantly increased after NET (p = 0.03). A good response to NET defined as a decrease in tumour size and/or decrease of Ki-67 was found to be associated with a longer duration of NET, a change of CD4+ T-cells and a higher number of CD68+ tumour-associated macrophages before the start of NET.

CONCLUSION

The immune microenvironment plays an important role in ER+/HER-2 negative BC. NET influences the composition and functional state of the infiltrating immune cells. Furthermore, changes in the immune microenvironment are also associated with treatment response.

Assessment of preoperative axillary nodal disease burden: breast MRI in locally advanced breast cancer before, during and after neoadjuvant endocrine therapy

Background

Axillary lymph node (LN) metastasis is one of the most important predictors of recurrence and survival in breast cancer, and accurate assessment of LN involvement is crucial. Determining extent of residual disease is key for surgical planning after neoadjuvant therapy. The aim of the study was to evaluate the diagnostic reliability of MRI for nodal disease in locally advanced breast cancer patients treated with neoadjuvant endocrine therapy (NET).

Methods

Thirty-three clinically node-positive locally advanced breast cancer patients who underwent NET and surgery were prospectively enrolled. Two radiologists reviewed the axillary nodes at 3 separate time points MRI examinations at baseline (before the first treatment regimen), interim (following at least 2 months after the first cycle and prior to crossing-over), and preoperative (after the final administration of therapy and immediately before surgery). According to LN status after surgery, imaging features and diagnostic performance were analyzed.

Results

All 33 patients had a target LN reduction, the greatest treatment benefit from week 8 to week 16.

There was a positive correlation between the maximal diameter of the most suspicious LN measured by MRI and pathology during and after NET, being highest at therapy completion (r = 0.6, P ≤ .001). Mean and median differences of maximal diameter of the most suspicious LN were higher with MRI than with pathology. Seven of 33 patients demonstrated normal posttreatment MRI nodal status (yrN0). Of these 7 yrN0, 3 exhibited no metastasis on final pathology (ypN0), 2 ypN1 and 2 ypN2. Reciprocally, MRI diagnosed 3 cases of ypN0 as yrN + . Diffusion -weighted imaging (DWI) was the only axillary node characteristic significant when associated with pathological node status (χ²(4) = 8.118, P = .072).

Conclusion

Performance characteristics of MRI were not completely sufficient to preclude surgical axillary staging. To our knowledge, this is the first study on MRI LN assessment following NET in locally advanced breast cancer, and further studies with larger sample sizes are required to consolidate the results of this preliminary study.

Trial Registration

Institutional Review Board approval was obtained (this current manuscript is from a prospective, open-label, randomized single-center cohort substudy of the NEOLETEXE trial). NEOLETEXE, a phase 2 clinical trial, was registered on March 23^rd, 2015 in the National trial database of Norway and approved by the Regional Ethical Committee of the South-Eastern Health Region in Norway; registration number: REK-SØ-84–2015.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09813-9.

The Clinical Impact of Neoadjuvant Endocrine Treatment on Luminal-like Breast Cancers and Its Prognostic Significance: Results from a Single-Institution Prospective Cohort Study

Purpose: Neoadjuvant endocrine treatment (NET) has become a useful tool for the downstaging of luminal-like breast cancers in postmenopausal patients. It enables us to increase breast- conserving surgery (BCS) rates, provides an opportunity for us to assess in vivo NET effectiveness, and allows us to study any biological changes that may act as valid biomarkers. The purpose of this study was to evaluate the safety and effectiveness of NET, and to assess the role of Ki67 proliferation rate changes as an indicator of endocrine responsiveness. Methods: From 2016 to 2020, a single-institution cohort of patients, treated with NET and further surgery, was evaluated. In patients with Ki67 ≥ 10%, a second core biopsy was performed after four weeks. Information regarding histopathological and clinical changes was gathered. Results: A total of 115 estrogen receptor-positive (ER+)/HER2-negative patients were included. The median treatment duration was 5.0 months (IQR: 2.0−6.0). The median maximum size in the surgical sample was 40% smaller than the pretreatment size measured by ultrasound (p < 0.0001). The median pretreatment Ki67 expression was 20.0% (IQR: 12.0−30.0), and was reduced to 5.0% (IQR: 1.8−10.0) after four weeks, and to 2.0% (IQR: 1.0−8.0) in the surgical sample (p < 0.0001). BCS was performed on 98 patients (85.2%). No pathological complete responses were recorded. A larger Ki67 fold change after four weeks was significantly related to a PEPI score of zero (p < 0.002). No differences were observed between luminal A- and B-like tumors, with regard to fold change and PEPI score. Conclusions: In our cohort, NET was proven to be effective for tumor size and Ki67 downstaging. This resulted in a higher rate of conservative surgery, aided in therapeutic decision making, provided prognostic information, and constituted a safe and well-tolerated approach.

The Present and Future of Neoadjuvant Endocrine Therapy for Breast Cancer Treatment

Simple Summary

The treatment of breast cancer has evolved considerably over the last two decades, leading toward individualized disease management. Hormone-sensitive breast cancers constitute the vast majority of cases and endocrine therapy is the mainstay of their treatment. On the other hand, neoadjuvant or pre-surgical treatments provide a number of advantages for tumor management. In this review we will discuss the existing evidence on neoadjuvant endocrine therapy, as well as its possible future indications.

Abstract

Endocrine therapy (ET) has established itself as an efficacious treatment for estrogen receptor-positive (ER+) breast cancers, with a reduction in recurrence rates and increased survival rates. The pre-surgical approach with chemotherapy (NCT) has become a common form of management for large, locally advanced, or high-risk tumors. However, a good response to NCT is not usually expected in ER+ tumors. Good results with primary ET, mainly in elderly women, have encouraged studies in other stages of life, and nowadays neoadjuvant endocrine treatment (NET) has become a useful approach to many ER+ breast cancers. The aim of this review is to provide an update on the current state of art regarding the present and the future role of NET.

Approaching Neoadjuvant Therapy in the Management of Early-Stage Breast Cancer

Neoadjuvant therapy is integral to the treatment of early-stage breast cancer. Goals of treatment include surgical downstaging of the tumor, rendering inoperable tumors resectable, and de-escalating axillary surgery in those with clinically positive nodes. Additionally, response to treatment provides important prognostic information regarding risk of recurrence and guides future adjuvant treatment. Although chemotherapy serves as the backbone of neoadjuvant treatment, an increased understanding of the tumor's clinical course as well as its molecular and genetic make-up aids in individualizing treatment and developing novel agents. This review summarizes current clinical approaches and the future direction to the management of breast cancer patients in the neoadjuvant setting.

Neoadjuvant endocrine therapy in women with operable breast cancer: A retrospective analysis of real-world use

BACKGROUND

A retrospective study of the real-world use of neoadjuvant endocrine therapy (NET) is important for standardizing its role in breast cancer care.

MATERIALS AND METHODS

In a consecutive series of women with operable breast cancer who received NET for ≥28 days, NET objectives, NET outcomes, adjuvant chemotherapy use after NET, and survivals, were examined for the correlation with clinicopathological factors.

RESULTS

NET objectives were for surgery extent reduction in 49 patients, surgery avoidance in 31, and treatment until scheduled surgery in 8. The mean duration of NET was 349.5 (range, 34-1923), 869.8 (range, 36-4859), and 55.8 (range, 39-113) days in the above cohorts (success: 79.6%, 64.5%, and 100%), respectively, with significant difference. In patients of the former two cohorts, better progression-free survival was significantly correlated with stage 0 or I, ductal carcinoma in situ or invasive ductal carcinoma, ≥71% estrogen receptor (ER) positivity, and the surgery extent reduction cohort than the other counterparts. Postoperative chemotherapy use was significantly correlated with lymph node metastasis, a high Ki67 labeling index, lymphovascular invasion, and a high Preoperative Endocrine Prognostic Index, at surgery after NET. Better recurrence-free survival after surgery was significantly correlated with high ER expression after NET and high PgR expression before and after NET.

CONCLUSIONS

NET can help to reduce the surgery extent or to avoid surgery in women with breast cancer of early-stage, ductal carcinoma, or high ER expression. NET may also contribute to appropriate decision of postoperative systemic therapy to improve survivals.

The Impact of the COVID-19 Pandemic on Surgical Management of Breast Cancer: Global Trends and Future Perspectives

INTRODUCTION

The rapid spread of COVID-19 across the globe is forcing surgical oncologists to change their daily practice. We sought to evaluate how breast surgeons are adapting their surgical activity to limit viral spread and spare hospital resources.

METHODS

A panel of 12 breast surgeons from the most affected regions of the world convened a virtual meeting on April 7, 2020, to discuss the changes in their local surgical practice during the COVID-19 pandemic. Similarly, a Web-based poll based was created to evaluate changes in surgical practice among breast surgeons from several countries.

RESULTS

The virtual meeting showed that distinct countries and regions were experiencing different phases of the pandemic. Surgical priority was given to patients with aggressive disease not candidate for primary systemic therapy, those with progressive disease under neoadjuvant systemic therapy, and patients who have finished neoadjuvant therapy. One hundred breast surgeons filled out the poll. The trend showed reductions in operating room schedules, indications for surgery, and consultations, with an increasingly restrictive approach to elective surgery with worsening of the pandemic.

CONCLUSION

The COVID-19 emergency should not compromise treatment of a potentially lethal disease such as breast cancer. Our results reveal that physicians are instinctively reluctant to abandon conventional standards of care when possible. However, as the situation deteriorates, alternative strategies of de-escalation are being adopted.

IMPLICATIONS FOR PRACTICE

This study aimed to characterize how the COVID-19 pandemic is affecting breast cancer surgery and which strategies are being adopted to cope with the situation.

How Effective is Neoadjuvant Endocrine Therapy (NET) in Downstaging the Axilla and Achieving Breast-Conserving Surgery?

BACKGROUND

Neoadjuvant endocrine therapy (NET) is effective in downstaging large hormone receptor-positive (HR+) breast cancers and increasing rates of breast-conserving surgery (BCS), but data regarding nodal pathologic complete response (pCR) are sparse. We reported nodal and breast downstaging rates with NET, and compared axillary response rates following NET and neoadjuvant chemotherapy (NAC).

METHODS

Consecutive stage I-III breast cancer patients treated with NET and surgery from January 2009 to December 2019 were identified from a prospectively maintained database. Nodal pCR rates were compared between biopsy-proven node-positive patients treated with NET, and HR+/HER2- patients treated with NAC from November 2013 to July 2019.

RESULTS

127 cancers treated with NET and 338 with NAC were included. NET recipients were older, more likely to have lobular and lower-grade tumors, and higher HR expression. With NET, the nodal pCR rate was 11% (4/38) of biopsy-proven cases, and the breast pCR rate was 1.6% (2/126). Nodal-dowstaging rates with NET and NAC were not significantly different (11% vs 18%; P = 0.37). Patients achieving nodal pCR with NET versus NAC were older (median age 70 vs 50, P = 0.004) and had greater progesterone receptor (PR) expression (85% vs 13%, P = 0.031), respectively. Of patients not candidates for BCS due to a large tumor relative to breast size, 36/47 (77%) became BCS-eligible with NET (median PR expression 55% vs 5% in those remaining ineligible, P < 0.05).

CONCLUSION

Although nodal pCR is more frequent than breast pCR, NET is more likely to de-escalate breast surgery than axillary surgery. However, with a nodal pCR rate of 11%, NET remains an option for downstaging node-positive patients without clear indications for NAC.

Neoadjuvant endocrine therapy in locally advanced estrogen or progesterone receptor-positive breast cancer: determining the optimal endocrine agent and treatment duration in postmenopausal women-a literature review and proposed guidelines

Introduction

For patients with locally advanced estrogen receptor or progesterone receptor-positive breast cancer, neoadjuvant endocrine therapy (NET) facilitates down-staging of the tumor and increased rates of breast-conserving surgery. However, NET remains under-utilized, and there are very limited clinical guidelines governing which therapeutic agent to use, or the optimal duration of treatment in postmenopausal women. This literature review aims to discuss the evidence surrounding (1) biomarkers for patient selection for NET, (2) the optimal neoadjuvant endocrine agent for postmenopausal women with locally advanced breast cancer, and (3) the optimal duration of NET. In addition, we make initial recommendations towards developing a clinical guideline for the prescribing of NET.

Method

A wide-ranging search of online electronic databases was conducted using a truncated PIC search strategy to identify articles that were relevant to these aims and revealed a number of key findings.

Results

Randomized trials have consistently demonstrated that aromatase inhibitors are more effective than tamoxifen, in terms of objective response rate and rate of BCS, and should be used as first-line NET. The three available aromatase inhibitors have so far been demonstrated to be biologically equivalent, with the choice of aromatase inhibitor not having been shown to affect clinical outcomes. There is increasing evidence for extending the duration of NET beyond 3 to 4 months, to at least 6 months or until maximal clinical response is achieved. While on-treatment levels of the proliferation marker Ki67 are predictive of long-term outcome, the choice of adjuvant therapy in patients who have received NET and then surgery is best guided by the preoperative endocrine prognostic index, or PEPI, which incorporates Ki67 with other clinical parameters.

Conclusion

This study reveals that in appropriately selected patients, NET can provide equivalent clinical benefit to neoadjuvant chemotherapy in the same cohort, if suitable treatments and durations are chosen. Our findings highlight the need for better defined biomarkers both for guiding patient selection and for measuring outcomes. Development of standard guidelines for the prescribing of NET has the potential to improve both clinical outcomes and quality of life in this patient cohort.

Invasive lobular breast cancer: A review of pathogenesis, diagnosis, management, and future directions of early stage disease

Invasive lobular carcinoma (ILC) is the second most common type of invasive breast cancer after invasive ductal carcinoma (IDC). Invasive lobular carcinoma has unique clinical, pathologic, and radiographic features which suggest that it is a distinct clinical entity; however, it is treated with the same treatment paradigms as IDC. Information regarding the specific treatment of ILC, including response to standard therapy, is sparse. Neoadjuvant treatment considerations are of great importance in this space as ILC is often found at a locally advanced stage. In this review, we summarize the classic features of ILC and the available data regarding efficacy of both endocrine therapy and chemotherapy in curative treatment of breast cancer.

Neoadjuvant endocrine treatment in early breast cancer: An overlooked alternative?

During the last decade neoadjuvant endocrine therapy (NET) has moved from being reserved for elderly and frail non-chemotherapy candidates to a primary systemic modality in selected patients with hormone sensitive breast cancer. Neoadjuvant hormonal treatment in patients with hormone receptor positive, HER-2 negative early breast cancer is proven to be an effective and safe option; it is associated with a higher rate of breast conserving surgery (BCS), may reduce the need for adjuvant chemotherapy and enables a delay of surgery for medical or practical reasons. Clinical responses range from 13% to 100% with at least 3 months of NET. Methods of assessing response should include MRI of the breast, particularly in lobular tumours. In studies comparing tamoxifen with aromatase inhibitors (AI), AI proved to be superior in terms of tumour response and rates of BCS. Change in Ki67 is accepted as a validated endpoint for comparing endocrine neoadjuvant agents. Levels of Ki67 during treatment are more closely related to long-term prognosis than pretreatment Ki67. Neoadjuvant endocrine therapy provides a unique opportunity for studies of endocrine responsiveness and the development of new experimental drugs combined with systemic hormonal treatment.