Real-World Data and Clinical Implications of Next-Generation Sequencing (NGS)-Based Analysis in Metastatic Breast Cancer Patients

Over the last two decades, the use of Next-Generation Sequencing (NGS) in medical oncology has increased the likelihood of identifying druggable mutations that may be potentially susceptible to targeted treatments. The European Society for Medical Oncology (ESMO) currently does not recommend the use of the NGS test to determine the therapeutic course of patients with metastatic breast cancer (mBC) in daily clinical practice. However, the aim of this work is to evaluate the potential contribution of the NGS test in selecting targeted therapies for patients with mBC. Data were retrospectively collected from 101 patients diagnosed with metastatic breast cancer and treated at the Modena Cancer Center between January 2015 and April 2022. A NGS test was performed on the tumor tissue of each patient at the Laboratory of Molecular Pathology of the University Hospital of Modena. This study analyzed the clinical-pathological characteristics and mutational profile of the population using NGS tests, with a focus on actionable mutations that could be targeted in advanced stages of clinical development. The indicator of this study was to quantify the actionable mutations that resulted in a change of cancer treatment. In total, 101 patients with metastatic breast cancer were analyzed, including 86 with luminal phenotype, 10 who were HER2-positive and 5 who were triple-negative. Median age was 52 years. NGS analysis was conducted on 47 samples of primary breast cancer, 52 on metastatic sites of disease and 2 on liquid biopsies. A total of 85 gene mutations were found. The most common mutations were identified in the PIK3CA (47%), FGFR (19%) and ERBB2 genes (12%), and to a lesser extent in other genes. Of the 61 patients with pathogenic mutations, 46 (75%) had at least one actionable mutation. Of these, nine received treatment with a molecular target drug: eight patients with a mutation of the PIK3CA gene were treated with alpelisib and fulvestrant; one patient with FGFR1/2 amplifications received TAS120. Median PFS for these patients was 3.8 months. The study results show that using the NGS test on cancer tissue of metastatic breast cancer could influence the therapeutic choices, considering the small sample size and limited follow-up. About 9% of the study population had their therapy modified based on the results of NGS. The growing number of detectable mutations and increased accessibility of the test may lead to a greater number of potential therapeutic implications for the NGS assay. Perspectives suggest that NGS analysis can be implemented in daily clinical practice, particularly in contexts where a Molecular Tumor Board (MTB) is active.

Thromboembolism and Adjuvant Endocrine Therapy (AET) in Hormone Receptor-Positive Early Breast Cancer (EBC): Did Treatment Evolution Change Incidence of the Adverse Event? A Meta-Analysis

The adjuvant endocrine therapy (AET) of HR+ EBC has been changing in recent years. Aromatase inhibitors (AIs) as an upfront strategy (or as part of a switch strategy) have been added to the choice of Tamoxifen (T) alone. Increased TE risk is well known in T-treated patients, while AIs have shown a reduced TE rate. By adding the cyclin dependent kinase 4/6 inhibitors (CDK4/6) to AIs, an increase in TE rate has been shown. We conducted this meta-analysis to evaluate the impact of the AETs on TE incidence. Twelve randomized phase III trials were included. Four trials evaluated the upfront strategy, 6 assessed the switch and 2 the combination with a CDK4/6 inhibitor. The new AETs did not significantly modify or affect the rate of TE events (OR 0.847, 95% CI, 0.528-1.366, P = .489). The OR for CDK4/6 inhibitor plus ET vs. ET was 3.635 (P = .002). Excluding the CDK4/6 inhibitors, the overall OR for AIs vs. T was 0.628 (P < .001), while it was 0.781 (P = .151) for switching T vs. continuing T for 5 years, and 0.52 (P < .0001) for the upfront strategies with AIs. The AIs alone or plus CDK4/6 inhibitors did not affect the rate of TE events. AIs as an upfront strategy is the safest AET, associated with the lowest TE incidence. The switch strategy increases TE rate, whereas the addition of CDK4/6 to the standard AET was shown to significantly increase TE events. The results of the currently ongoing trials with CDK4/6 inhibitors will help obtain additional data to evaluate any differences among the different CDK4/6 inhibitors and clarify the weight of TE adverse events in the benefit/risk balance of this new adjuvant strategy.

Adjuvant Endocrine Therapy in Premenopausal Women With Hormone Receptor-Positive Early-Stage Breast Cancer: Risk Stratification in a Real-World Setting

BACKGROUND

Ovarian function suppression (OFS) and hormone therapy (HT) represent an adjuvant option in premenopausal hormone receptor-positive early breast cancer (HR+EBC). The SOFT-TEXT trials showed improved outcomes upon receiving aromatase inhibitors (AIs)/OFS.

METHODS

In order to estimate the magnitude of absolute improvements, we conducted a retrospective study applying composite risk (CR) to 237 premenopausal HR+EBC patients.

RESULTS

Overall, 119 of these received tamoxifen (T)/OFS and 118 received AIs/OFS. The median age was 45 years (ys). After a median follow up of 65 months, recurrence was 6.7% in T patients and 10.2% in AI ones. CR (cutoff: 2.67) and ET duration (five-year cutoff) was found to have a significant impact on DFS. Invasive disease-free survival (IDFS) at 5 ys amounted to 82.9% for a CR>2.67 and 95% with CR

CONCLUSION

In a real-world setting, treatment options for premenopausal patients who are candidates for HT and OFS should take risk status into account. Therefore, every effort should be made to maintain patient adherence to treatment in order to manage toxicities and improve outcomes.

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Key Words

• Adjuvant hormone therapy
• Aromatase inhibitors
• Breast cancer
• Ovarian function suppression
• Tamoxifen

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Affiliation(s)

Raffaella D'Onofrio Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
Claudia Omarini Division of Medical Oncology, Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy; Gruppo Oncologico Italiano per la Ricerca Clinica (GOIRC), Parma, Italy
Angela Toss Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy; Department of Oncology and Hematology, Azienda Ospedaliero-Universitaria di Modena, Modena, Italy
Isabella Sperduti Biostatistics Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
Federico Piacentini Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy; Gruppo Oncologico Italiano per la Ricerca Clinica (GOIRC), Parma, Italy
Monica Barbolini Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
Laura Cortesi Division of Medical Oncology, Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
Elena Barbieri Division of Medical Oncology, Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy
Elisa Pettorelli Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
Chiara Chiavelli Department of Oncology and Hematology, Azienda Ospedaliero-Universitaria di Modena, Modena, Italy; Department of Medical and Surgical Sciences, University of Modena and Reggio Emilia, Modena, Italy
Massimo Dominici Division of Medical Oncology, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy; Department of Oncology and Hematology, Azienda Ospedaliero-Universitaria di Modena, Modena, Italy
Luca Moscetti Division of Medical Oncology, Department of Oncology and Hematology, University Hospital of Modena, Modena, Italy; Gruppo Oncologico Italiano per la Ricerca Clinica (GOIRC), Parma, Italy.

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Targeting PI3K/AKT/mTOR Pathway in Breast Cancer: From Biology to Clinical Challenges

Breast cancer (BC) is the most common women cancer and cause of cancer death. Despite decades of scientific progress in BC treatments, the clinical benefit of new drugs is modest in several cases. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway mutations are frequent in BC (20-40%) and are significant causes of aggressive tumor behavior, as well as treatment resistance. Improving knowledge of the PI3K/AKT/mTOR pathway is an urgent need. This review aims to highlight the central role of PI3K-mTORC1/C2 mutations in the different BC subtypes, in terms of clinical outcomes and treatment efficacy. The broad base of knowledge in tumor biology is a key point for personalized BC therapy in the precision medicine era.

Predictive factors for relapse in triple-negative breast cancer patients without pathological complete response after neoadjuvant chemotherapy

Introduction

Triple-negative breast cancer (TNBC) patients who do not obtain pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) present higher rate of relapse and worse overall survival. Risk factors for relapse in this subset of patients are poorly characterized. This study aimed to identify the predictive factors for relapse in TNBC patients without pCR after NACT.

Methods

Women with TNBC treated with NACT from January 2008 to May 2020 at the Modena Cancer Center were included in the analysis. In patients without pCR, univariate and multivariable Cox analyses were used to determine factors predictive of relapse.

Results

We identified 142 patients with a median follow-up of 55 months. After NACT, 62 patients obtained pCR (43.9%). Young age at diagnosis (&lt;50 years) and high Ki-67 (20%) were signi!cantly associated with pCR. Lack of pCR after NACT resulted in worse 5-year event-free survival (EFS) and overall survival (OS). Factors independently predicting EFS in patients without pCR were the presence of multifocal disease [hazard ratio (HR), 3.77; 95% CI, 1.45–9.61; p=0.005] and residual cancer burden (RCB) III (HR, 3.04; 95% CI, 1.09–9.9; p=0.04). Neither germline BRCA status nor HER2-low expression were associated with relapse.

Discussion

These data can be used to stratify patients and potentially guide treatment decision-making, identifying appropriate candidates for treatment intensi!cation especially in neo-/adjuvant setting.

Concomitant administration of proton pump inhibitors does not significantly affect clinical outcomes in metastatic breast cancer patients treated with ribociclib

BACKGROUND

Gastric pH changes by proton-pump-inhibitors (PPIs) were found to affect progression-free survival (PFS) in metastatic breast cancer (mBC) patients treated with palbociclib. The current study was aimed at investigating whether the same effect could occur in patients treated with ribociclib.

PATIENTS AND METHODS

Patients with hormone-positive/HER-2-negative mBC candidates for first-line treatment with ribociclib were enrolled in this retrospective-cohort study. Patients were classified as "no concomitant PPIs" or "concomitant PPIs"; PPI administration covered the entire or not less than 2/3 of treatment with ribociclib. All clinical interventions were made according to clinical practice.

RESULTS

A total of 128 patients were consecutively enrolled in the study; 78 belonged to the "no concomitant PPIs" group and 50 to the "concomitant PPIs" group. One hundred and six patients were endocrine-sensitive and received ribociclib and letrozole, while 22 were endocrine-resistant and were treated with ribociclib and fulvestrant. The most prescribed PPI was lansoprazole. According to PFS, patients taking PPIs had a PFS almost superimposable to those assuming ribociclib and endocrine therapy alone (35.3 vs. 49.2 months, p = 0.594). No difference in PFS was observed in estrogen-sensitive or estrogen-resistant mBC in the presence or absence of concomitant PPI treatment (p = 0.852). No correlation with adverse events was found including grade>2 hematological toxicities.

CONCLUSIONS

The present study supports the hypothesis that the concomitant use of PPIs does not compromise the efficacy of ribociclib in a real-life setting.

Role of Intrinsic Subtype Analysis with PAM50 in Hormone Receptors Positive HER2 Negative Metastatic Breast Cancer: A Systematic Review

Endocrine therapy (ET), associated with CDK 4/6 inhibitors, represents the first choice of treatment for HR+/HER2- metastatic breast cancer (mBC). Primary or secondary endocrine resistance could develop; however validated biomarkers capable of predicting such a conditions are not available. Several studies have shown that HR+/HER2- mBC comprises five intrinsic subtypes. The purpose of this systematic review was to analyze the potential correlations between intrinsic subtype, efficacy of treatment, and patient outcome. Five papers that analyzed the intrinsic subtype with PAM50 assay in patients (pts) with HR+/HER2- mBC treated with ET (alone or in combination) within seven phase III clinical trials (EGF30008, BOLERO-2, PALOMA-2,3, MONALEESA-2,3,7) were identified. Non-luminal subtypes are more frequent in endocrine-resistant pts and in metastatic sites (vs. primary tumors), have less benefit from ET, and worse prognosis. Among these, HER2-enriched subtypes are similar to HER2+ tumors and benefit from the addition of anti-HER2 agents (lapatinib) and, for less clear reasons, of ribociclib (unconfirmed data for palbociclib and everolimus). Basal-like subtypes are similar to triple-negative tumors, making them more sensitive to chemotherapy. The intrinsic subtype is also not static but can vary over time with the evolution of the disease. Currently, the intrinsic subtype does not play a decisive role in the choice of treatment in clinical practice, but has potential prognostic and predictive value that should be further investigated.

T-DM1 efficacy in trastuzumab-pertuzumab pre-treated HER2 positive metastatic breast cancer patients: a meta-analysis

Background

Current guidelines consider T-DM1 the standard 2^nd line therapy for HER2 positive metastatic breast cancer (MBC) patients following trastuzumab (T) + pertuzumab (P) and taxane 1^st line treatment. Despite this, there are no prospective studies supporting this sequence.

Methods

We performed a meta-analysis using real world data to determine the efficacy of T-DM1 after 1^st line TP in HER2 positive MBC patients. We used a random-effect model to find differences in the rate of 1-year progression free survival (PFS) between TP pre-treated population and the EMILIA phase III pivotal trial.

Results

Seven studies were eligible. The meta-analysis showed a combined 1-year PFS risk difference for T-DM1 efficacy after TP in 2^nd or more lines of -0.122, with lower and upper limits of -0.253 and 0.010, respectively (p = 0.07), with low heterogeneity among studies (I² 0.01%, p = 0.836). Considering the four studies on T-DM1 in 2^nd line setting, 1-year PFS risk was -0.034 (95% CI -0.207 – 0,139; p = 0.701) (I² 0.01%, p = 0.91).

Conclusion

Overall, the efficacy of T-DM1 after TP seems to be similar to that previously reported in the EMILIA trial. In the second line setting, data are not mature enough to confirm T-DM1 efficacy in TP pre-treated population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09556-7.

Quality of life of therapies for hormone receptor positive advanced/metastatic breast cancer: Regulatory aspects and clinical impact in Europe

In recent years, the number of trials incorporating health-related quality of life (HRQoL) data has increased. The impact of HRQoL on regulatory decision making in the European context and on clinical practice is not well established. We conducted an analysis of the role of QoL data extracted from the clinical trials of the drugs approved for hormone receptor positive/HER2-negative advanced/metastatic breast cancer (mBC). The results from the HRQoL were collected and a meta-analysis was performed to evaluate the impact of experimental drugs compared to standard treatments. The results showed a non-detrimental effect in HRQoL from the new treatments. As regards the approval process, from an examination of the European Medicine Agency (EMA) documents, HRQoL was reported nonextensively and contained and discussed in the European assessment reports (EPARs) for eleven trials in the approval process and cited in three cases in the EPARs and summary of medicinal product characteristics (SmPC). An effort should be made by all the stakeholders to increase the visibility of the HRQoL results in order to allow increased consideration in the approval process to make QoL data more easily and visibly available for the clinician and the patients. The evaluation should be reflected in the SmPC in order to increase the amount of information provided to the physician.

Circulating and Intracellular miRNAs as Prognostic and Predictive Factors in HER2-Positive Early Breast Cancer Treated with Neoadjuvant Chemotherapy: A Review of the Literature

MicroRNAs (miRNA) are small noncoding RNAs that can act as both oncogene and tumor suppressors. Deregulated miRNA expression has been detected in human cancers, including breast cancer (BC). Considering their important roles in tumorigenesis, miRNAs have been investigated as potential prognostic and diagnostic biomarkers. Neoadjuvant setting is an optimal model to investigate in vivo the mechanism of treatment resistance. In the management of human epidermal growth factor receptor-2 (HER2)-positive early BC, the anti-HER2-targeted therapies have drastically changed the survival outcomes. Despite this, growing drug resistance due to the pressure of therapy is relatively frequent. In the present review, we focused on the main miRNAs involved in HER2-positive BC tumorigenesis and discussed the recent evidence on their predictive and prognostic value.

Thromboembolism (TE) and adjuvant endocrine therapy (AET) in hormone receptor positive (HR+) early breast cancer (EBC): Did the evolution of treatment change the incidence of the adverse event? A metanalysis

e12516

Background: The AET of HR+ EBC has been changing in the recent years. Aromatase inhibitors (AI) as upfront, or in a planned switch strategy after Tamoxifen (T), have been added to the choice of T alone. An increased risk of TE is well known in the T treated patients while AIs have showed a reduced rate of TE. Recently, adding the cyclin dependent kinase 4/6 inhibitors (CDK4/6) abemaciclib to AIs, has showed a positive impact in the high risk HR+ EBC subgroups, but we are seeing an increase of the TE rate. We conducted this meta-analysis to evaluate the impact of the new AETs on the incidence of TE if compared to the standard monotherapy. Methods: We performed a meta-analysis of the randomized phase III trials comparing the experimental AETs and the endocrine standard therapy. A random-effect model to find differences in the rate of TE events between the experimental treatments and the standard therapy has been used. Results: Twelve phase III trials were included. Five trials evaluated the upfront strategy, 6 studies the switch and one the combination with a CDK4/6inhibitor (i.e. abemaciclib). Overall, the new AETs did not significantly modify or affect the rate of TE events (OR 0.708, 0.444-1.130, p = 0.148) with high heterogeneity among studies (I2 87, p < 0.0001). Excluding the abemaciclib trial, the incidence of TE is reduced (OR 0.609, 0.462-0.802, p < 0.0001) with a moderate heterogeneity among the studies (I2 59, p < 0.006). Considering the upfront strategies with AIs, the TE events are reduced (OR 0.507, 0.394-0.651, p < 0.0001) but they are not if we consider the trials in which T is used upfront before AIs (OR 0.762, 0.546-1.065, p = 0.112). Conclusions: Overall, the new treatments (AIs alone or plus CDK4/6 inhibitors) did not affect the rate in TE events. AIs as upfront strategy is the safest AETs of HR+ EBC, being associated to the lowest incidence of TE. The switch strategy increases the TE rate whereas the addition of abemaciclib to the standard AET showed to significantly increase the TE events. The results of the currently ongoing trials with the CDK4/6 inhibitors will help to obtain additional data to evaluate any differences among the different CDK4/6 inhibitors and to clarify the weight of the TE adverse events in the balance of benefit/risk of this new adjuvant strategy.

TDM-1 efficacy in trastuzumab-pertuzumab pre-treated HER2 positive metastatic breast cancer patients: A meta-analysis

e13010

Background: Based on the results reported in Emilia trial population, current guidelines consider TDM-1 the standard second-line therapy for HER2 positive metastatic breast cancer (MBC) patients. Despite that, there are no prospective studies supporting the efficacy of TDM-1 following trastuzumab (T) + pertuzumab (P) and taxane first-line treatment. Currently, only real-world data have investigated this sequence with controversial results Methods: We performed a meta-analysis of the available real world data to determine the efficacy of TDM-1 after first-line TP in HER2 positive MBC patients. We used a random-effect model to find differences in the rate of 1-year progression free survival (PFS) between TP pre-treated population and the phase III Emilia trial (T pre-treated population). Results: Seven studies were eligible, in three of them data were from sub-group population analysis. The meta-analysis showed a combined 1-years PFS risk difference for TDM-1 efficacy after TP in second or more lines of -0.122, with lower and upper limits of -0.253 and 0.010, respectively (p=0.07) , with low heterogeneity among studies (I2 < 0.0001, p =0.836). Considering the four studies on TDM-1 in second-line setting, 1-years PFS risk was -0.034 (95% CI -0.207 – 0,139; p=0.701) (I2 < 0.0001, p =0.91). Conclusions: Results from the meta-analysis show that the efficacy of TDM-1 after TP double-block seems to be similar to the previously reported in Emilia trial. In the second line setting, available data are not mature enough to confirm TDM-1 efficacy in TP pre-treated population. Currently, TP pretreated patients should receive TDM-1 as indicated in the guidelines.

The Role of Exosomes in Breast Cancer Diagnosis

The importance of molecular re-characterization of metastatic disease with the purpose of monitoring tumor evolution has been acknowledged in numerous clinical guidelines for the management of advanced malignancies. In this context, an attractive alternative to overcome the limitations of repeated tissue sampling is represented by the analysis of peripheral blood samples as a 'liquid biopsy'. In recent years, liquid biopsies have been studied for the early diagnosis of cancer, the monitoring of tumor burden, tumor heterogeneity and the emergence of molecular resistance, along with the detection of minimal residual disease. Interestingly, liquid biopsy consents the analysis of circulating tumor cells, circulating tumor DNA and extracellular vesicles (EVs). In particular, EVs play a crucial role in cell communication, carrying transmembrane and nonmembrane proteins, as well as metabolites, lipids and nucleic acids. Of all EVs, exosomes mirror the biological fingerprints of the parental cells from which they originate, and therefore, are considered one of the most promising predictors of early cancer diagnosis and treatment response. The present review discusses current knowledge on the possible applications of exosomes in breast cancer (BC) diagnosis, with a focus on patients at higher risk.

Two-month stop in mammographic screening significantly impacts on breast cancer stage at diagnosis and upfront treatment in the COVID era

Introduction

The present analysis aims to evaluate the consequences of a 2-month interruption of mammographic screening on breast cancer (BC) stage at diagnosis and upfront treatments in a region of Northern Italy highly affected by the severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) virus.

Methods

This retrospective single-institution analysis compared the clinical pathological characteristics of BC diagnosed between May 2020 and July 2020, after a 2-month screening interruption, with BC diagnosed in the same trimester of 2019 when mammographic screening was regularly carried out.

Results

The 2-month stop in mammographic screening produced a significant decrease in in situ BC diagnosis (−10.4%) and an increase in node-positive (+11.2%) and stage III BC (+10.3%). A major impact was on the subgroup of patients with BC at high proliferation rates. Among these, the rate of node-positive BC increased by 18.5% and stage III by 11.4%. In the subgroup of patients with low proliferation rates, a 9.3% increase in stage III tumors was observed, although node-positive tumors remained stable. Despite screening interruption, procedures to establish a definitive diagnosis and treatment start were subsequently carried out without delay.

Conclusion

Our data showed an increase in node-positive and stage III BC after a 2-month stop in BC screening. These findings support recommendations for a quick restoration of BC screening at full capacity, with adequate prioritization strategies to mitigate harm and meet infection prevention requirements.

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Due to the COVID19 pandemic, several mammographic screening services were disrupted.

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A 2-month stop in BC screening led to decreased in situ BC and increased node-positive and stage III BC diagnosis.

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A major impact was on the subgroup of patients with BC at high proliferation rates.

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Despite screening interruption, procedures to start treatments were subsequently carried out without delay.

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Restoration of BC screening at full capacity with infection prevention requirements is recommended.

Modulation of Mutational Landscape in HER2-Positive Breast Cancer after Neoadjuvant Chemotherapy

INTRODUCTION

In early-stage HER2 positive breast cancer (BC) patients, tumor response to neoadjuvant chemotherapy (NACT) predict survival outcomes. Patients achieving less than pathological complete response (pCR) have a worse prognosis, however, this group is heterogeneous. Nowadays limited data on predictive/prognostic biomarkers in patients with residual cancer disease are available.

METHODS

Using next-generation sequencing technology, we evaluated a panel of 21 cancer genes in a group of HER2 positive BC patients with residual disease after NACT. A control group of patients who achieved the pCR was selected too. The BC mutational profile was analyzed on both the tumor diagnostic biopsy and matched residual disease.

RESULTS

Overall, the detection rate of mutations was 79% in the No-pCR group versus 90% in the pCR cohort and 98% in the residual BC. The most mutated genes were TP53 and PIK3CA. No correlations between single gene mutations and survival outcomes were found. In no-pCR cohort, 52% of patients had different mutational profile after NACT, 69% of them had an increased in the number of mutated genes. Mutational profile changes from diagnostic biopsy to residual BC were a negative prognostic factor in term of relapse free survival: recurrence probability in different gene profile sub-group was 42% vs 0% in the same profile one (P = .019).

CONCLUSIONS

Treatment selective pressure on tumor cells due to NACT changed the gene mutational profile in more than half of BC patient with residual tumor disease. Treatment-induced gene mutations significantly increase the risk of relapse. Profiling primary and residual BC is a major step in order to further personalized adjuvant treatment strategy.

Combined endocrine approaches vs endocrine therapy alone as first line treatment in elderly patients with hormone receptor-positive, HER2 negative, advanced breast cancer: to prescribe for the patient or the physician? A meta-analysis of phase II and III randomized clinical trials

Background

Elderly patients are underrepresented in clinical study where combined endocrine strategies were compared to endocrine therapy (ET) in hormone receptors positive, HER2 negative, metastatic breast cancer. The role of the new endocrine approaches in elderly women is still unclear.

Methods

We performed a meta-analysis of first line phase II/III randomized trials on ET versus combined strategies considering clinical benefit and safety profile. Trials with hazard ratio (HR) for PFS in elderly patients were included.

Results

Overall, the meta-analysis showed a PFS advantage for the experimental arms [HR 0.77, p 0.016] with a significant high/moderate heterogeneity [I2 65.46%, p 0.005]. For patients on CDK 4/6 inhibitors and ET, HR was 0.57 (p < 0.0001), with low heterogeneity [I2 0.0001%, p 0.96]. Hematological adverse events, as well as diarrhea with Abemaciclib, were significantly higher in elderly population.

Conclusions

The magnitude of PFS benefit due to the combined strategies in elderly patients is similar to those reported in the overall clinical trial population. Adding CDK4/6 inhibitors to ET significantly prolongs PFS, even if toxicity profile have to be carefully considered. Future trials should be designed taking into account patients’ age, geriatric assessment and comorbidity.

Predictive Role Of Body Composition Parameters In Operable Breast Cancer Patients Treated With Neoadjuvant Chemotherapy

Background

Fat tissue is strongly involved in BC tumorigenesis inducing insulin resistance, chronic inflammation and hormonal changes. Computed tomography (CT) imaging instead of body mass index (BMI) gives a reliable measure of skeletal muscle mass and body fat distribution. The impact of body composition parameters (BCPs) on chemosensitivity is still debated. We examined the associations between BCPs and tumor response to neoadjuvant chemotherapy (NC) in patients treated for operable breast cancer (BC).

Methods

A retrospective review of BC patients treated with NC in Modena Cancer Center between 2005 and 2017 was performed. BCPs, such as subcutaneous fat area (SFA), visceral fat area (VFA), lumbar skeletal muscle index (LSMI) and liver-to-spleen (L/S) ratio were calculated by Advance workstation (General Electric), software ADW server 3.2 or 4.7. BMI and BCPs were correlated with pathological complete response (pCR) and survival outcomes.

Results

407 patients were included in the study: 55% with BMI < 25 and 45% with BMI ≥ 25. 137 of them had pre-treatment CT scan imagines. Overweight was significantly associated with postmenopausal status and older age. Hormonal receptor positive BC was more frequent in overweight patients (p<0.05). Postmenopausal women had higher VFA, fatty liver disease and obesity compared to premenopausal patients. No association between BMI classes and tumor response was detected. High VFA and liver steatosis were negative predictive factors for pCR (pCR rate: 36% normal VFA vs 20% high VFA, p= 0.048; no steatosis 32% vs steatosis 13%, p=0.056). Neither BMI classes nor BCPs significantly influenced overall survival and relapse-free survival.

Conclusion

Visceral adiposity as well as steatosis were closely involved in chemosensitivity in BC patients treated with NC. Their measures from clinically acquired CT scans provide significant predictive information that outperform BMI value. More research is required to evaluate the relationship among adiposity site and survival outcomes.

Distinct HR expression patterns significantly affect the clinical behavior of metastatic HER2+ breast cancer and degree of benefit from novel anti-HER2 agents in the real world setting

We analyzed data from 738 HER2‐positive metastatic breast cancer (mbc) patients treated with pertuzumab‐based regimens and/or T‐DM1 at 45 Italian centers. Outcomes were explored in relation to tumor subtype assessed by immunohistochemistry (IHC). The median progression‐free survival at first‐line (mPFS1) was 12 months. Pertuzumab as first‐line conferred longer mPFS1 compared to other first‐line treatments (16 vs. 9 months, p = 0.0001), regardless of IHC subtype. Median PFS in second‐line (mPFS2) was 7 months, with no difference by IHC subtype, but it was more favorable with T‐DM1 compared to other agents (7 vs. 6 months, p = 0.03). There was no PFS2 gain in patients with tumors expressing both hormonal receptors (HRs; p = 0.17), while a trend emerged for tumors with one HR (p = 0.05). Conversely, PFS2 gain was significant in HRs‐negative tumors (p = 0.04). Median overall survival (mOS) was 74 months, with no significant differences by IHC subtypes. Survival rates at 2 and 3 years in patients treated with T‐DM1 in second‐line after pertuzumab were significantly lower compared to pertuzumab‐naïve patients (p = 0.01). When analyzed by IHC subtype, the outcome was confirmed if both HRs or no HRs were expressed (p = 0.02 and p = 0.006, respectively). Our results confirm that HRs expression impacts the clinical behavior and novel treatment‐related outcomes of HER2‐positive tumors when treatment sequences are considered. Moreover, multivariate analysis showed that HRs expression had no effect on PFS and OS. Further studies are warranted to confirm our findings and clarify the interplay between HER2 and estrogen receptor pathways in HER2‐positive (mbc) patients.

What's new?

About half of breast cancers positive for human epidermal growth factor (HER2) also express hormone receptors but the impact of hormone receptor status on the success of HER2‐directed treatments is not fully explored. Here the authors retrospectively assessed tumor behavior and treatment outcomes in 738 women with HER2+ metastatic breast cancer treated with new generation anti‐HER2 agents. Distinct hormone receptor expression patterns significantly affected the progression free and overall survival, justifying further studies to define optimal treatment regimens and the interplay between hormone receptor and HER2 signaling.

First-Line Treatment for Endocrine-Sensitive Bone-Only Metastatic Breast Cancer: Systematic Review and Meta-analysis

In the last decade, several clinical trials have investigated novel endocrine combinations for the first-line treatment of hormone receptor-positive metastatic breast cancer. Nevertheless, the use of combinations for the first-line treatment of bone-only disease is widely discussed as a result of its indolent natural history. We performed a comprehensive search of phase 3 randomized clinical trials published in the literature through September 2018. Our aim was to explore the role of the new endocrine approaches in bone-only metastatic breast cancer, suggesting a possible strategy for their selection. In particular, we evaluated the comparative risk of adverse event occurrence during these treatments. A total of 6 studies were deemed suitable for meta-analysis: the Monaleesa-2, Monaleesa-7, Monarch-3, Paloma-2, SWOG, and Alliance trials. Overall, the novel strategies were shown to improve progression-free survival in bone-only disease (hazard ratio = 0.65; 95% confidence interval, 0.49-0.86; P = .003). Combinations with cyclin-dependent kinase inhibitors improved progression-free survival (hazard ratio = 0.54; 95% confidence interval, 0.39-0.75; P < .001) with an acceptable toxicity profile. Abemaciclib was associated with increased anemia and gastrointestinal toxicity (especially diarrhea), whereas palbociclib was associated with increased leukopenia (but not neutropenia) compared to the other compounds. Increased aspartate aminotransferase levels were reported for both ribociclib and abemaciclib. The combination of cyclin-dependent kinase 4/6 inhibitors and endocrine therapy represents an effective and well-tolerated approach for first-line treatment in bone-only disease settings. Because no direct comparison between the 3 cyclin-dependent kinase 4/6 inhibitors is available, the selection of the most appropriate treatment should be based on toxicity profile as well as patient preference and copathologies.

Endocrine-based targeted combination versus endocrine therapy alone as first-line treatment in elderly patients with hormone receptor-positive advanced breast cancer: Meta-analysis of phase II and III randomized clinical trials

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Background: Combined endocrine approaches have been widely investigated as first-line treatment in hormone receptors positive metastatic breast cancer. In particular, multiple randomized trials showed that the addiction of CDK (cyclin-dependent kinase) 4/6 inhibitors to endocrine therapy (ET) increase progression free survival (PFS). Elderly patients (aged ≥65 years) are under represented in most of the clinical studies. Moreover, due to the multi-morbidity and the major toxicity associated with the targeted agents, the combination strategy in that subgroup is widely discussed. The present meta-analysis aimed to understand the role of the new endocrine approaches in women aged ≥65 years. Methods: This meta-analysis included first line phase II/III randomized published trials comparing (ET) to the experimental strategy. Trials with no data about hazard ratios (HR) for PFS in the subgroup of patients aged ≥65 years were excluded. The heterogeneity of the data was evaluated by Chi-square Q test and I2 statistic. Results: 8 studies were included in the analysis. 4 trials (Paloma1/TRIO-18, Paloma2, Monaleesa2, Monarch3) investigated the role of CDK 4/6 inhibitors, 2 trials (SWOG and FACT) analysed the combination of Fulvestrant plus Aromatase Inhibitors, while other two trials explored the association of ET with Bevacizumab (LEA) and Temsirolimus (HORIZON), respectively. Overall, the meta-analysis showed a PFS advantage for the experimental arms [HR 0.77, p 0.016] with a significant high/moderate heterogeneity [I2 65.46%, p 0.005]. The 4 studies adding CDK4/6 inhibitors to ET showed a significant improvement in PFS compared to ET alone. No significant advantages for the addition of anti-angiogenic agents or Fulvestrant to ET have been found in elderly population subgroup. Conclusions: The novel experimental combo-strategies in the first line setting showed an improvement in PFS in the subgroup of elderly patients. Adding CDK4/6 inhibitors to ET significantly prolongs PFS as compared to ET alone. The magnitude of PFS benefit due to addition of CDK4/6 inhibitors to ET is age-independent.

Abstract P1-18-06: First-line treatment for endocrine sensitive bone-only metastatic breast cancer: Is more always better?

The standard first-line for endocrine sensitive metastatic breast cancer (BC) is represented by endocrine therapy. Several phase III clinical trials searched for more effective endocrine strategies. Nevertheless, the use of combinations for the first-line treatment of bone-only disease (BoD) is widely discussed, due to its indolent course. Our meta-analysis aims to explore the role of new endocrine strategies in BoD.

A systematic review of electronic databases was conducted to identify the phase III clinical trials comparing the standard AI to novel experimental strategies. The hazard ratios (HR) for PFS were pooled in a meta-analysis. The heterogeneity of the data was evaluated by Chi-square Q test and I2 statistic.

8 studies were included in the analyses. 4 trials explored the role of CDK4/6 inhibitors (Monaleesa2 and 7, Monarch3 and Paloma2), 2 trials analyzed Fulvestrant + AI (SWOG and FACT), one trial studied Fulvestrant monotherapy (FALCON), while one trial evaluated the association between Bevacizumab and Letrozole (ALLIANCE). 6 trials reported data regarding the BoD, while 2 trials included the BoD in the non-visceral disease. Overall, the meta-analyses showed a PFS advantage for the experimental arms [HR 0.70 p 0.012], with a significant moderate/high heterogeneity [I2 66.48% p 0.004]. Only the FALCON and Paloma2 showed a significant improvement in PFS, respectively for Fulvestrant and Palbociclib + Letrozole. Considering only trials reporting data for BoD, the experimental arms significantly improved the PFS [HR 0.66 p 0.005], with a low/moderate non-significant heterogeneity [I2 44.95% p 0.106].

The novel strategies showed to be able to improve the PFS of BoD. Nonetheless, only Palbociclib + Letrozole provided statistically significant data of advantage in this setting. In clinical trials, BoD is often included in the non-visceral disease subgroup. Future clinical trials should take into account the differences in natural history and better prognosis of BoD, in order to define the best approach to these patients.

Citation Format: Toss A, Venturelli M, Sperduti I, Isca C, Molinaro E, Barbieri E, Piacentini F, Omarini C, Cortesi L, Cascinu S, Moscetti L. First-line treatment for endocrine sensitive bone-only metastatic breast cancer: Is more always better? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-18-06.

Differential molecular pathways expression in HER2 positive early breast cancer according to hormone receptor status

PURPOSE

Hormone receptors (HR) status in HER2 + breast cancer (BC) is a recognized stratification factor with relevant clinical implication. According to HR expression, HER2 + BC show different clinical characteristics, treatment sensitivity and prognosis. The interaction between HR and HER2 pathways remains incompletely understood.

METHODS

Thirty-four HER2 + BC were included: 18 tumors with HER2+/HR + and 16 with HER2+/HR-. The expression of 770 genes and 13 molecular pathways were evaluated using Nanostring PanCancer Pathway panel performed on FFPE BC biopsies.

RESULTS

Gene expression analysis identified 127 genes with significantly different expression between the two cohorts. 83% of these genes were overexpressed in HER2+/HR- cohort. Globally, 23% of them belonged to PI3K pathway (41 genes), 15% to Trascriptional regulation (26 genes) and 12% to MAPK (22 genes). Regarding pathway expression, PI3K, MAPK and NOTCH were significantly differently expressed between the two groups (p = 0.003, p = 0.0018 and p = 0.02, respectively), all of them were overexpressed in HER2+/HR- tumors.

CONCLUSIONS

According to HR status, HER2 + tumors express different pathways profiles: the overexpression of PI3K, MAPK and NOTCH pathways in HER2+/HR- group could justify different survival outcomes and treatment sensitivity. The identification of tumor driver pathways may be a useful instrument for individualized pathway-directed therapies. Further clinical implications are warranted.

A multicenter REtrospective observational study of first-line treatment with PERtuzumab, trastuzumab and taxanes for advanced HER2 positive breast cancer patients. RePer Study

We carried out a retrospective observational study of 264 HER2-positive advanced breast cancer (ABC) patients to explore the efficacy of first-line treatment with pertuzumab/trastuzumab/taxane in real-world setting. Survival data were analyzed by Kaplan Meier curves and log rank test. Median follow-up, length of pertuzumab/trastuzumab/taxane treatment and of pertuzumab, trastuzumab maintenance were 21, 4 and 15 months, respectively. The response rate was 77.3%, and the clinical benefit rate 93.6%. Median progression-free survival (mPFS) was 21 months, and median overall survival (mOS) was not reached. When comparing patients by trastuzumab-pretreatment, similar PFS were observed, although a longer OS was reached in trastuzumab-naïve patients (p = 0.02). Brain metastases at baseline and their development in course of therapy were associated with significantly shorter PFS (p = 0.0006) and shorter OS, although at a not fully statistically relevant extent (p = 0.06). The addition of maintenance endocrine therapy (ET) to pertuzumab/trastuzumab maintenance was associated with longer PFS (p = 0.0001), although no significant differences were detected in OS (p = 0.31). Results were confirmed by propensity score analysis (p = 0.003 and p = 0.46, respectively). In multivariate models, longer PFS was related to lower Performance Status (PS) (p = 0.07), metastatic stage at diagnosis (p = 0.006) and single metastatic site (p < 0.0001). An OS advantage was observed with lower PS (p < 0.0001), single metastatic site (p = 0.004), no prior exposure to trastuzumab (p = 0.004) and response to pertuzumab-based treatment (p = 0.003). Our results confirm that trastuzumab/pertuzumab/taxane is the standard of care as first-line treatment of patients with HER2-positive ABC even in the real-world setting. Moreover, the double-maintenance therapy (HER2 block and ET) is strongly recommended when feasible.

Genomic alterations at the basis of treatment resistance in metastatic breast cancer: clinical applications

The standard of care for breast cancer has gradually evolved from empirical treatments based on clinical-pathological characteristics to the use of targeted approaches based on the molecular profile of the tumor. Consequently, an increasing number of molecularly targeted drugs have been developed. These drugs target specific alterations, called driver mutations, which confer a survival advantage to cancer cells. To date, the main challenge remains the identification of predictive biomarkers for the selection of the optimal treatment. On this basis, we evaluated a panel of 25 genes involved in the mechanisms of targeted treatment resistance, in 16 primary breast cancers and their matched recurrences, developed during treatment. Overall, we found a detection rate of mutations higher than that described in the literature. In particular, the most frequently mutated genes were ERBB2 and those involved in the PI3K/AKT/mTOR and the MAPK signaling pathways. The study revealed substantial discordances between primary tumors and metastases, stressing the need for analysis of metastatic tissues at recurrence. We observed that 85.7% of patients with an early-stage or locally advanced primary tumor showed at least one mutation in the primary tumor. This finding could explain the subsequent relapse and might therefore justify more targeted adjuvant treatments. Finally, the mutations detected in 50% of relapsed tissues could have guided subsequent treatment choices in a different way. This study demonstrates that mutation events may be present at diagnosis or arise during cancer treatment. As a result, profiling primary and metastatic tumor tissues may be a major step in defining optimal treatments.

Clinical and molecular predictors of long-term response in HER2 positive metastatic breast cancer patients

BACKGROUND

HER2+ metastatic breast cancer (MBC) is a poor prognosis disease, unusually curable. To date, no predictive factors have been clearly correlated with long-term response to anti-HER2 agents.

METHODS

54 HER2+ MBC patients treated with HER2 targeted therapy as first line treatment were analysed: 40 with a time to progression longer than 3 years in Long Responders (LR) group and 14 with a progression disease within one year of anti-HER2 therapy in a control group named Early Progressors (EP). The expression of 770 genes and 13 molecular pathways were evaluated using Nanostring PanCancer pathway panel performed on FFPE BC tissues.

RESULTS

Considering baseline patients and tumor characteristics, EP women had more CNS spread and more metastatic burden of disease compared to LR (p > 0.05). Gene expression analysis identified 30 genes with significantly different expression in the two cohorts; five were driver genes (BRCA1, PDGFRA, AR, PHF6 and MSH2). The majority of these genes were over-expressed, mainly in LR patients, and encoded growth factors, pro- or anti-inflammatory interleukins and DNA repair factors. Only four genes were down regulated, all in EP group (TNFSF10, CACNG1, IL20RB and BRCA1). Most of these genes were involved in MAPK and PI3K pathways. MAPK pathway was differently expressed between LR and EP (p = 0.05). PI3K was the only pathway overexpressed in EP patients.

CONCLUSIONS

Whole genome expression analysis comparing LR vs. EP identified a group of genes that may predict more favourable long-term outcomes. Up-regulation of MAPK and down-regulation of PI3K pathway could be a positive predictive factors. Further clinical implications are warranted.

ABBREVIATIONS

BC: breast cancer; MBC: metastatic breast cancer; LR: long responder; EP: early progressor; FFPE: formalin-fixed paraffin-embedded; CNS: central nervous system; PFS: progression free survival; OS: overall survival.

Spotlight on triptorelin in the treatment of premenopausal women with early-stage breast cancer

Endocrine treatment represents the cornerstone of endocrine-sensitive premenopausal early breast cancer. The estrogen blockade plays a leading role in the therapeutic management of hormone receptor-positive breast cancer together with surgery, radiotherapy, and selective antiestrogen treatments. For several years, selective estrogen receptor modulators, such as tamoxifen, have represented the mainstay of therapy. The role of amenorrhea has been extensively elucidated in the past year: the benefit observed with chemotherapy-induced amenorrhea has strengthened its therapeutic role. Luteinizing hormone-releasing hormone (LHRH) has been introduced in oncology practice to induce amenorrhea in order to increase the advantage obtained from endocrine treatment. Triptorelin is one of the most widely used LHRH analogs currently available in clinical practice. It was recently investigated in two major clinical trials that studied the role of complete estrogen blockade in the premenopausal setting. Both showed the clinical benefit due to ovarian suppression treatment, primarily in high-risk patients. Furthermore, triptorelin and other LHRH analogs have recently been investigated in the attempt to preserve the ovarian function in young patients. The medical treatment of early breast cancer is always evolving in the effort to search for safe and efficacious treatments. The role of LHRH analogs is actually well recognized as contributing to the improvement of the medical treatment of premenopausal women with early breast cancer.

Lapatinib and Renal Impairment: A Case Report

This clinical report describes durable control of disease in a postmenopausal patient receiving hemodialysis and letrozole plus lapatinib since the diagnosis of HER2-positive, estrogen receptor-positive liver metastasis from breast cancer after anastrozole plus trastuzumab failure.

Neoadjuvant treatments in triple-negative breast cancer patients: where we are now and where we are going

Triple-negative breast cancer (TNBC) remains the poorest-prognosis breast cancer (BC) subtype. Gene expression profiling has identified at least six different triple-negative subtypes with different biology and sensitivity to therapies. The heterogeneous nature of TN tumors may justify the difficulty in treating this BC subtype. Several targeted agents have been investigated in clinical trials without demonstrating a clear survival benefit. Therefore, systemic chemotherapy remains the cornerstone of current clinical practice. Improving the knowledge of tumor biology is mandatory for patient management. In stages II and III, neoadjuvant systemic treatment is an effective option of care. The achievement of a pathological complete response represents an optimal surrogate for survival outcome as well as a test for tumor drug sensitivity. In this review, we provide a brief description of the main predictive biomarkers for tumor response to systemic treatment. Moreover, we review the treatment strategies investigated for TNBCs in neoadjuvant settings focusing on experimental drugs such as immunotherapy and poly [ADP-ribose] polymerase inhibitors that hold promise in the treatment of this aggressive disease. Therefore, the management of TNBC represents an urgent, current, unmet need in daily clinical practice. A key recommendation is to design biology-driven clinical trials wherein TNBC patients may be treated on the basis of tumor molecular profile.

A retrospective multicentric observational study of trastuzumab emtansine in HER2 positive metastatic breast cancer: a real-world experience

We addressed trastuzumab emtansine (T-DM1) efficacy in HER2+ metastatic breast cancer patients treated in real-world practice, and its activity in pertuzumab-pretreated patients. We conducted a retrospective, observational study involving 23 cancer centres, and 250 patients. Survival data were analyzed by Kaplan Meier curves and log rank test. Factors testing significant in univariate analysis were tested in multivariate models. Median follow-up was 15 months and median T-DM1 treatment-length 4 months. Response rate was 41.6%, clinical benefit 60.9%. Median progression-free and median overall survival were 6 and 20 months, respectively. Overall, no differences emerged by pertuzumab pretreatment, with median progression-free and median overall survival of 4 and 17 months in pertuzumab-pretreated (p=0.13), and 6 and 22 months in pertuzumab-naïve patients (p=0.27). Patients who received second-line T-DM1 had median progression-free and median overall survival of 3 and 12 months (p=0.0001) if pertuzumab-pretreated, and 8 and 26 months if pertuzumab-naïve (p=0.06). In contrast, in third-line and beyond, median progression-free and median overall survival were 16 and 18 months in pertuzumab-pretreated (p=0.05) and 6 and 17 months in pertuzumab-naïve patients (p=0.30). In multivariate analysis, lower ECOG performance status was associated with progression-free survival benefit (p<0.0001), while overall survival was positively affected by lower ECOG PS (p<0.0001), absence of brain metastases (p 0.05), and clinical benefit (p<0.0001). Our results are comparable with those from randomized trials. Further studies are warranted to confirm and interpret our data on apparently lower T-DM1 efficacy when given as second-line treatment after pertuzumab, and on the optimal sequence order.

Metronomic Capecitabine Effectively Blocks Leptomeningeal Carcinomatosis From Breast Cancer: A Case Report and Literature Review

Patient: Female, 57

Final Diagnosis: Meningeal carcinomatosis from breast cancer

Symptoms: Seizures

Medication: —

Clinical Procedure: —

Specialty: Oncology

Impact of time to surgery after neoadjuvant chemotherapy in operable breast cancer patients

BACKGROUND

The optimal time interval between the end of neoadjuvant systemic therapy (NST) and breast surgery is still unclear. It is not known if a delay in surgery might influence the benefit of primary chemotherapy. The aim of this study is to evaluate the relationship between time to surgery (TTS) and survival outcomes.

PATIENTS AND METHODS

According to TTS, women with diagnosis of BC treated with NST were divided into two cohorts: group A = 21 days or fewer and group B = longer than 21 days. OS and RFS were estimated and compared according to TTS and known prognostic factors.

RESULTS

A total of 319 patients were included in the study: 61 in group A and 258 in group B. Median TTS was 34 days. No association between clinical stage, nuclear grade, type of chemotherapy, type of surgery and TTS was detected. OS and RFS were significantly worse for group B compared with group A, with a hazard ratio of 3.1 (95% CI, 1.1-8.6 p = 0.03) and 3.1 (95% CI, 1.3-7.1 p = 0.008) respectively. Multivariate analysis confirmed that TTS was an independent prognostic factor in term of OS (p = 0.03) and RFS (p = 0.01). Even in the subgroup of patients with pCR, TTS continued to be an independent prognostic factor for both OS and RFS (p = 0.05 and p = 0.03).

CONCLUSIONS

TTS after NST seems to influence survival outcomes. BC patients underwent surgery within 21 days experienced maximal benefit from previous treatment: this advantage is consistent and maintained over time.