Low-Dose Oral Cyclophosphamide and Methotrexate Maintenance for Hormone Receptor-Negative Early Breast Cancer: International Breast Cancer Study Group Trial 22-00

A stimuli-responsive drug delivery system based on konjac glucomannan, carboxymethyl chitosan and mesoporous polydopamine nanoparticles

A stimuli-responsive drug delivery system is developed for controlled delivery of curcumin (Cur) and chemo-photothermal therapy of breast cancer (BC). Cur is first loaded into mesoporous polydopamine nanoparticles (mPDA NPs) by π-π stacking, and then the Cur loaded mPDA NPs (mPDA NPs@Cur) are encapsulated in the hydrogels prepared through the crosslinking of oxidized konjac glucomannan (oxKGM) and carboxymethyl chitosan (CMCS). Owing to the pH-sensitivity of the hydrogels and the outstanding photothermal conversion capability of mPDA NPs, the release of Cur from the hydrogels can be greatly accelerated in acidic media upon near infrared (NIR) irradiation. Cytotoxicity assay indicates that the hydrogels have significant cytotoxicity against murine breast tumor cell 4 T1 while the drug-free hydrogels (oxKGM/CMCS/mPDA NPs) show good biocompatibility. In addition, the hyperthermia generated upon NIR irradiation can lead to the apoptosis of cancer cells, achieving chemo-photothermal combination therapy of BC. Release kinetics study reveals that the release of Cur from the hydrogels follows zero-order model.

Metronomic Chemotherapy in Breast Cancer as a Strategy to Deliver More Sustainable and Less Toxic Treatments: Time to Debunk the Myth?

Breast cancer is the most commonly diagnosed cancer in women, worldwide. With the increasing burden of breast cancer, the search for more tolerable and sustainable treatments is required, to result in broader access to cancer treatments. Metronomic chemotherapy defines the use of chemotherapy agents based on low-dose, continuous regimens, as opposed to traditional treatments administered for limited intervals, at higher dose. The use of metronomic chemotherapies has been envisioned often as a way to reduce toxicity while maintaining similar efficacy, and result in reduced health system resource utilization, while tailoring some special populations' needs, such as the older adults with cancer. In our review, we provide a revision of the data available on the use of metronomic chemotherapy in breast cancer, as stratified per setting of use and subtypes of diseases. Clinical trials evaluating head-to-head metronomic and nonmetronomic schedules of chemotherapies broadly failed to meet their endpoints of noninferiority and/or superiority in term of safety, showing more often similar burden of adverse effect. Efficacy was also usually comparable. Data on financial implications appeared limited, and not conclusive of economic and health system benefits with the use of metronomic schedules. Our review of the evidence suggests that broad implementation of metronomic chemotherapy to enhance sustainability and safety may be not appropriate in all settings, as data for the optimized use are still warranted. The use of metronomic chemotherapy in breast cancer as a mean to improve tolerability, reduce treatment-related complications and associate costs and enhance sustainability of cancer treatments should not be pursued as an ultimate solution, in all settings of breast cancer treatment. Standard treatments having robustly proved to improve patient outcomes are to be prioritised for first, unless data suggest otherwise with these regimens.

Adjuvant Atezolizumab for Early Triple-Negative Breast Cancer: The ALEXANDRA/IMpassion030 Randomized Clinical Trial

Importance

Triple-negative breast cancer is an aggressive subtype with a high incidence in young patients, a high incidence in non-Hispanic Black women, and a high risk of progression to metastatic cancer, a devastating sequela with a 12- to 18-month life expectancy. Until recently, one strategy for treating early-stage triple-negative breast cancer was chemotherapy after surgery. However, it was not known whether the addition of immune therapy to postsurgery chemotherapy would be beneficial.

Objective

To evaluate the addition of immune therapy in the form of atezolizumab to postoperative chemotherapy in patients with the high-risk triple-negative breast cancer subtype.

Design, Setting, and Participants

In this open-label international randomized phase 3 trial conducted in more than 330 centers in 31 countries, patients undergoing surgery as initial treatment for stage II or III triple-negative breast cancer were enrolled between August 2, 2018, and November 11, 2022. The last patient follow-up was on August 18, 2023.

Interventions

Patients were randomized (1:1) to receive standard chemotherapy for 20 weeks with (n = 1101) or without (n = 1098) the immune therapy drug atezolizumab for up to 1 year.

Main Outcomes and Measures

The primary end point was invasive disease-free survival (time between randomization and invasive breast cancer in the same or opposite breast, recurrence elsewhere in the body, or death from any cause).

Results

The median age of enrolled patients was 53 years and most self-reported as being of Asian or White race and neither Latino nor Hispanic ethnicity. The study independent data monitoring committee halted enrollment at 2199 of 2300 planned patients. All patients stopped atezolizumab following a planned early interim and futility analysis. The trial continued to a premature final analysis. With invasive disease-free survival events in 141 patients (12.8%) treated with atezolizumab-chemotherapy and 125 (11.4%) with chemotherapy alone (median follow-up, 32 months), the final stratified invasive disease-free survival hazard ratio was 1.11 (95% CI, 0.87-1.42; P = .38). Compared with chemotherapy alone, the regimen of atezolizumab plus chemotherapy was associated with more treatment-related grade 3 or 4 adverse events (54% vs 44%) but similar incidences of fatal adverse events (0.8% vs 0.6%) and adverse events leading to chemotherapy discontinuation. Chemotherapy exposure was similar in the 2 treatment groups.

Conclusions and Relevance

The addition of the immune therapy drug atezolizumab to chemotherapy after surgery did not provide benefit among patients with triple-negative breast cancer who are at high risk of recurrent disease.

Trial Registration

ClinicalTrials.gov Identifier: NCT03498716.

Metronomic chemotherapy and breast cancer: a critical evaluation of its role in the new landscape of therapeutics

INTRODUCTION

Breast cancer (BC) remains a prevalent and challenging malignancy among women, with significant advancements in treatment strategies over the past decades. Traditional chemotherapy has been progressively supplemented by newer modalities, including Antibody-Drug Conjugates (ADCs), Immunotherapy (IO), and Targeted Therapies (TT). Despite these advancements, there remains a critical need for strategies that maintain efficacy while minimizing toxicity.

AREAS COVERED

This review delves into metronomic chemotherapy (MC), a novel approach involving the frequent administration of low-dose chemotherapy without prolonged breaks. We explore MC's impact across various breast cancer subtypes, such as Estrogen Receptor-Positive (ER+), HER2-Positive, and Triple-Negative Breast Cancer (TNBC). The literature reviewed highlights MC's mechanisms, including its anti-angiogenic, immunomodulatory, and antiproliferative effects, and its potential to improve treatment tolerability and address drug resistance.

EXPERT OPINION

MC represents a promising adjunct to existing therapies, particularly in advanced or resistant cases. Its unique dosing schedule could offer sustained antitumor activity with reduced toxicity, making it a viable option for long-term management. However, further research is warranted to establish optimal dosing regimens, identify predictive biomarkers, and delineate its role within combination treatment strategies. Clarifying these aspects could refine MC's application, potentially reshaping treatment paradigms and enhancing patient outcomes in breast cancer management.

Optimizing Postneoadjuvant Treatment of Residual Breast Cancer With Adjuvant Bevacizumab Alone, With Metronomic or Standard-Dose Chemotherapy: A Combined Analysis of DFCI 05-055 and DFCI 09-134/TBCRC 012/ABCDE Clinical Trials

BACKGROUND

Breast cancer patients with residual disease after neoadjuvant therapy have increased risk of recurrence. Novel therapies to decrease this risk are urgently needed.

METHODS

Two clinical trials (05-055 and 09-134) offered adjuvant bevacizumab-based therapy to stage I-III breast cancer patients with residual disease after neoadjuvant chemotherapy. Study 05-055 evaluated four treatment regimens: bevacizumab (cohort A); bevacizumab with metronomic cyclophosphamide and methotrexate (CM) (cohort B); and bevacizumab with body surface area-dosed capecitabine (cohorts C); or flat-dosed capecitabine (cohort D). The primary endpoint was feasibility and tolerability. In 09-134, patients were randomized to bevacizumab with or without CM; the primary endpoint was recurrence-free survival (RFS). Study 09-134 closed prematurely for lack of accrual. A pooled survival analysis with participants from 05-055 and 09-134 was conducted.

RESULTS

Among 213 total patients (05-055, n = 163; 09-134, n = 50), the most common adverse events (AEs) of any grade were headache (49.3%) and fatigue (57.3%). Grade 3-4 AEs were highest in cohorts C (71.4%) and D (72.5%). The 36-month RFS was 58.0% with bevacizumab monotherapy, 62.3% with bevacizumab plus CM, and 72.7%-75.0% with bevacizumab plus capecitabine (depending on schedule). Treatment with capecitabine was independently associated with improved RFS in triple-negative breast cancer (TNBC) (HR: 0.47; 95% CI, 0.23-0.96).

CONCLUSION

This pooled analysis demonstrates that postneoadjuvant bevacizumab plus capecitabine may be associated with improved RFS, especially in TNBC. Each regimen carries moderate toxicity, and despite these treatments, patients with residual disease after neoadjuvant therapy still experience high rates of recurrence, indicating that new strategies are warranted.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov, NCT00121134 (DFCI Protocol Number: 05-055); NCT00925652 (DFCI Protocol Number: 09-134).

"Cyclophosphamide and analogues; a matter of dose and schedule for dual anticancer activities"

Cyclophosphamide and ifosfamide are major alkylating agents but their therapeutics uses are limiting by the toxicity due to several toxicities. Indeed conventional chemotherapies are generally used with the maximum tolerated dose. In contrast, metronomic schedule aims to get a minimum dose for efficacy with a good safety. Depending on the dose, their mechanisms of action are different and offer a dual activity: at high dose, cyclophosphamide is mainly used in graft conditioning for its immunosuppressive properties, while at metronomic dose it is used as an immunoactive agent. Currently, at metronomic dose, cyclophosphamide is studied in clinic against various types of cancer, alone or in combination with others anticancer drugs (anti-angiogenic, immune-modulating agents, immune checkpoints blockers, vaccines, radiotherapy, others conventional anticancer agents), as a nth-line or first-line treatment. More than three quarters of clinical studies show promising results, mostly in breast, ovarian and prostate cancers. Taking advantage of the immune system, use dual antitumor action's chemotherapy is clearly a therapeutic strategy that deserves to be confirmed in order to improve the efficacy/toxicity balance of anticancer treatments, and to use CPM or analogues as a standard of care.

Multiplexed high-throughput immune cell imaging in patients with high-risk triple negative early breast cancer: Analysis from the International Breast Cancer Study Group (IBCSG) Trial 22-00

BACKGROUND

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer (BC) subtype, with dismal prognosis and limited option in advanced settings, yet stromal tumor infiltrating lymphocytes (sTILs) in this subtype has a predictive role.

PATIENTS AND METHODS

The International Breast Cancer Study Group (IBCSG) Trial 22-00 is a randomized phase III clinical trial testing the efficacy of low-dose metronomic oral Cyclophosphamide-Methotrexate (CM) maintenance following standard adjuvant chemotherapy treatment for early-stage hormone receptor-negative breast cancer patients. A case-cohort sampling was used. We characterized immune cells infiltrates in patients with TNBC by 6 plex immunofluorescence (IF) staining for CD4, FOXP3, CD3, cytokeratine and CD8 RESULTS: We confirmed that high immune CD3+ T cells as well as stromal and intra-epithelial Tregs (CD4+Foxp3+ T cells) infiltrates were associated with a better Distant Recurrence-Free Interval (DRFI), especially in LN+ patient, regardless of the treatment. More importantly, we showed that the spatial distribution of immune cells at baseline is crucial, as CM maintenance was detrimental for T cells excluded LN+ TNBC patients.

CONCLUSIONS

immune spatial classification on immune cells infiltrates seems crucial and could help patients' selection in clinical trial and greatly improve responses to specific therapies.

Metronomic chemotherapy and drug repurposing: A paradigm shift in oncology

Cancer represents a significant global health and economic burden due to its high mortality rates. While effective in some instances, traditional chemotherapy often falls short of entirely eradicating various types of cancer. It can cause severe side effects due to harm to healthy cells. Two therapeutic approaches have risen to the forefront to address these limitations: metronomic chemotherapy (MCT) and drug repurposing. Metronomic chemotherapy is an innovative approach that breaks from traditional models. It involves the administration of chemotherapeutic regimens at lower doses, without long drug-free intervals that have previously been a hallmark of such treatments. This method offers a significant reduction in side effects and improved disease management. Simultaneously, drug repurposing has gained considerable attraction in cancer treatment. This approach involves utilizing existing drugs, initially developed for other therapeutic purposes, as potential cancer treatments. The application of known drugs in a new context accelerates the timeline from laboratory to patient due to pre-existing safety and dosage data. The intersection of these two strategies gives rise to a novel therapeutic approach named 'Metronomics.' This approach encapsulates the benefits of both MCT and drug repurposing, leading to reduced toxicity, potential for oral administration, improved patient quality of life, accelerated clinical implementation, and enhanced affordability. Numerous clinical studies have endorsed the efficacy of metronomic chemotherapy with tolerable side effects, underlining the potential of Metronomics in better cancer management, particularly in low- and middle-income countries. This review underscores the benefits and applications of metronomic chemotherapy and drug repurposing, specifically in the context of breast cancer, showcasing the promising results of pre-clinical and clinical studies. However, we acknowledge the necessity of additional clinical investigations to definitively establish the role of metronomic chemotherapy in conjunction with other treatments in comprehensive cancer management.

Differential Benefit of Metronomic Chemotherapy Among Triple-Negative Breast Cancer Subtypes Treated in the IBCSG Trial 22-00

PURPOSE

To explore whether specific triple-negative breast cancer (TNBC) molecular subtypes are predictive for a benefit from maintenance low-dose cyclophosphamide and methotrexate (CM) in the adjuvant IBCSG 22-00 phase III clinical trial.

EXPERIMENTAL DESIGN

RNA sequencing was performed on a selection of 347 TNBC formalin-fixed paraffin-embedded (FFPE) tumor samples following a case-cohort-like sampling. TNBC subtypes were computed on gene expression data. The association between TNBC subtypes and treatment outcome was assessed using a Cox proportional-hazards interaction test.

RESULTS

Immunomodulatory (IM) and basal-like/immune activated (BLIA) molecular subtypes showed a significant survival benefit when treated with low-dose CM [disease-free survival (DFS): HR, 0.5; 95% confidence interval (CI), 0.28-0.89; Pinteraction = 0.018 and HR, 0.49; 95% CI, 0.27-0.9; Pinteraction = 0.021]. Moreover, a high expression of regulatory T-cell immune signature was associated with a better prognosis in the CM arm, in line with a potential immunomodulating role of cyclophosphamide. In contrast, a worse outcome was observed in tumors with a mesenchymal (M) subtype treated with low-dose CM (DFS: HR, 1.9; 95% CI, 1.2-3; Pinteraction = 0.0044).

CONCLUSIONS

Our results show a differential benefit of low-dose CM therapy across different TNBC subtypes. Low-dose CM therapy could be considered as a potential strategy for TNBC tumors with IM subtype in the early-disease setting.

Nanoformulations-Based Metronomic Chemotherapy: Mechanism, Challenges, Recent Advances, and Future Perspectives

Cancer-related death is a significant health and economic burden worldwide, and some conventional chemotherapy is associated with limited effectiveness in completely curing various cancers, severe adverse effects, and destruction of healthy cells. To overcome the complications associated with conventional treatment, metronomic chemotherapy (MCT) is extensively suggested. In this review, we aim to highlight the importance of MCT over conventional chemotherapeutic approach with emphasis on nanoformulations-based MCT, their mechanism, challenges, recent advances, and future perspectives. Nanoformulations-based MCT revealed remarkable antitumor activity in both preclinical and clinical settings. For example, the metronomic scheduling of oxaliplatin-loaded nanoemulsion and polyethylene glycol-coated stealth nanoparticles incorporating paclitaxel were proven very effective in tumor-bearing mice and rats, respectively. Additionally, several clinical studies have demonstrated the benefit of MCT with acceptable tolerance. Moreover, metronomic might be a promising treatment strategy for improving cancer care in low- and middle-income nations. However, an appropriate alternative to a metronomic regimen for an individual ailment, suitable combinational delivery and scheduling, and predictive biomarkers are certain parts that remain unanswered. Further clinical-based comparative research studies are mandatory to be performed before entailing this treatment modality in clinical practice as alternative maintenance therapy or in place of transferring to therapeutic management.

Metronomic Chemotherapy for Metastatic Breast Cancer Treatment: Clinical and Preclinical Data between Lights and Shadows

Metronomic chemotherapy (mCHT), defined as continuous administration of low-dose chemotherapeutic agents with no or short regular treatment-free intervals, was first introduced to the clinic in international guidelines in 2017, and, since then, has become one of the available strategies for the treatment of advanced breast cancer (ABC). Despite recent successes, many unsolved practical and theoretical issues remain to be addressed. The present review aims to identify the "lights and shadows" of mCHT in preclinical and clinical settings. In the preclinical setting, several findings indicate that one of the most noticeable effects of mCHT is on the tumor microenvironment, which, over the last twenty years, has been demonstrated to be pivotal in supporting tumor cell survival and proliferation. On the other hand, the direct effects on tumor cells have been less well-defined. In addition, critical items to be addressed are the lack of definition of an optimal biological dose (OBD), the method of administration of metronomic schedules, and the recognition and validation of predictive biomarkers. In the clinical context-where mCHT has mainly been used in a metastatic setting-low toxicity is the most well-recognised light of mCHT, whereas the type of study design, the absence of randomised trials and uncertainty in terms of doses and drugs remain among the shadows. In conclusion, growing evidence indicates that mCHT is a suitable treatment option for selected metastatic breast cancer (MBC) patients. Moreover, given its multimodal mechanisms of action, its addition to immunological and targeted therapies might represent a promising new approach to the treatment of MBC. More preclinical data are needed in this regard, which can only be obtained through support for translational research as the key link between basic science and patient care.

Precision Breast Cancer Medicine: Early Stage Triple Negative Breast Cancer-A Review of Molecular Characterisation, Therapeutic Targets and Future Trends

Personalised approaches to the management of all solid tumours are increasing rapidly, along with wider accessibility for clinicians. Advances in tumour characterisation and targeted therapies have placed triple-negative breast cancers (TNBC) at the forefront of this approach. TNBC is a highly heterogeneous disease with various histopathological features and is driven by distinct molecular alterations. The ability to tailor individualised and effective treatments for each patient is of particular importance in this group due to the high risk of distant recurrence and death. The mainstay of treatment across all subtypes of TNBC has historically been cytotoxic chemotherapy, which is often associated with off-target tissue toxicity and drug resistance. Neoadjuvant chemotherapy is commonly used as it allows close monitoring of early treatment response and provides valuable prognostic information. Patients who achieve a complete pathological response after neoadjuvant chemotherapy are known to have significantly improved long-term outcomes. Conversely, poor responders face a higher risk of relapse and death. The identification of those subgroups that are more likely to benefit from breakthroughs in the personalised approach is a challenge of the current era where several targeted therapies are available. This review presents an overview of contemporary practice, and promising future trends in the management of early TNBC. Platinum chemotherapy, DNA damage response (DDR) inhibitors, immune checkpoint inhibitors, inhibitors of the PI3K-AKT-mTOR, and androgen receptor (AR) pathways are some of the increasingly studied therapies which will be reviewed. We will also discuss the growing evidence for less-developed agents and predictive biomarkers that are likely to contribute to the forthcoming advances in this field. Finally, we will propose a framework for the personalised management of TNBC based upon the integration of clinico-pathological and molecular features to ensure that long-term outcomes are optimised.

Metronomic Chemotherapy for Advanced Prostate Cancer: A Literature Review

Metastatic castration-resistant prostate cancer (mCRPC) is the ultimately lethal form of prostate cancer. Docetaxel chemotherapy was the first life-prolonging treatment for mCRPC; however, the standard maximally tolerated dose (MTD) docetaxel regimen is often not considered for patients with mCRPC who are older and/or frail due to its toxicity. Low-dose metronomic chemotherapy (LDMC) is the frequent administration of typically oral and off-patent chemotherapeutics at low doses, which is associated with a superior safety profile and higher tolerability than MTD chemotherapy. We conducted a systematic literature review using the PUBMED, EMBASE, and MEDLINE electronic databases to identify clinical studies that examined the impact of LDMC on patients with advanced prostate cancer. The search identified 30 reports that retrospectively or prospectively investigated LDMC, 29 of which focused on mCRPC. Cyclophosphamide was the most commonly used agent integrated into 27/30 (90%) of LDMC regimens. LDMC resulted in a clinical benefit rate of 56.8 ± 24.5% across all studies. Overall, there were only a few non-hematological grade 3 or 4 adverse events reported. As such, LDMC is a well-tolerated treatment option for patients with mCRPC, including those who are older and frail. Furthermore, LDMC is considered more affordable than conventional mCRPC therapies. However, prospective phase III trials are needed to further characterize the efficacy and safety of LDMC in mCRPC before its use in practice.

CDK12 promotes tumorigenesis but induces vulnerability to therapies inhibiting folate one-carbon metabolism in breast cancer

Cyclin-dependent kinase 12 (CDK12) overexpression is implicated in breast cancer, but whether it has a primary or only a cooperative tumorigenic role is unclear. Here, we show that transgenic CDK12 overexpression in the mouse mammary gland per se is sufficient to drive the emergence of multiple and multifocal tumors, while, in cooperation with known oncogenes, it promotes earlier tumor onset and metastasis. Integrative transcriptomic, metabolomic and functional data reveal that hyperactivation of the serine-glycine-one-carbon network is a metabolic hallmark inherent to CDK12-induced tumorigenesis. Consistently, in retrospective patient cohort studies and in patient-derived xenografts, CDK12-overexpressing breast tumors show positive response to methotrexate-based chemotherapy targeting CDK12-induced metabolic alterations, while being intrinsically refractory to other types of chemotherapy. In a retrospective analysis of hormone receptor-negative and lymph node-positive breast cancer patients randomized in an adjuvant phase III trial to 1-year low-dose metronomic methotrexate-based chemotherapy or no maintenance chemotherapy, a high CDK12 status predicts a dramatic reduction in distant metastasis rate in the chemotherapy-treated vs. not-treated arm. Thus, by coupling tumor progression with metabolic reprogramming, CDK12 creates an actionable vulnerability for breast cancer therapy and might represent a suitable companion biomarker for targeted antimetabolite therapies in human breast cancers.

Finding biomarkers for targeted therapy is a promising approach to treat cancer. Here, the authors show that in breast cancer preclinical models and patients, CDK12 promotes tumourigenesis but induces selective vulnerability to therapies that target folate one-carbon metabolism.

Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03)

PURPOSE

The PALLAS study investigated whether the addition of palbociclib, an oral CDK4/6 inhibitor, to adjuvant endocrine therapy (ET) improves invasive disease-free survival (iDFS) in early hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In this analysis, we evaluated palbociclib exposure and discontinuation in PALLAS.

METHODS

Patients with stage II-III HR+, HER2- disease were randomly assigned to 2 years of palbociclib with adjuvant ET versus ET alone. The primary objective was to compare iDFS between arms. Continuous monitoring of toxicity, dose modifications, and early discontinuation was performed. Association of baseline covariates with time to palbociclib reduction and discontinuation was analyzed with multivariable competing risk models. Landmark and inverse probability weighted per-protocol analyses were performed to assess the impact of drug persistence and exposure on iDFS.

RESULTS

Of the 5,743 patient analysis population (2,840 initiating palbociclib), 1,199 (42.2%) stopped palbociclib before 2 years, the majority (772, 27.2%) for adverse effects, most commonly neutropenia and fatigue. Discontinuation of ET did not differ between arms. Discontinuations for non-protocol-defined reasons were greater in the first 3 months of palbociclib, and in the first calendar year of accrual, and declined over time. No significant relationship was seen between longer palbociclib duration or ≥ 70% exposure intensity and improved iDFS. In the weighted per-protocol analysis, no improvement in iDFS was observed in patients receiving palbociclib versus not (hazard ratio 0.89; 95% CI, 0.72 to 1.11).

CONCLUSION

Despite observed rates of discontinuation in PALLAS, analyses suggest that the lack of significant iDFS difference between arms was not directly related to inadequate palbociclib exposure. However, the discontinuation rate illustrates the challenge of introducing novel adjuvant treatments, and the need for interventions to improve persistence with oral cancer therapies.

The prolonged clinical benefit with metronomic chemotherapy (VEX regimen) in metastatic breast cancer patients

Metronomic chemotherapy is a treatment option for metastatic breast cancer (MBC) patients who require prolonged disease control without cumulative toxicity. Data available on the efficacy and tolerability of prolonged usage of metronomic therapy are limited. We analyzed patients with MBC, enrolled in a clinical trial, who obtained a prolonged clinical benefit for a duration of at least 12 months with vinorelbine 30 or 40 mg orally three times a week, cyclophosphamide 50 mg daily and capecitabine 500 mg three times a day (VEX regimen). The patients were treated at the European Institute of Oncology, Milan. We identified 67 MBC patients. The median age before starting the VEX regimen was 53 years. There were 59 patients (88%) who had hormone-receptors positive and HER2 negative BC. We had 37 patients who received VEX as the first-line treatment for MBC, while 30 patients were pretreated. The objective response rate was 49% (95% CI, 37-62). The median duration of VEX treatment after the first year was 14 months (min-max range 0.3-81.3 months). The progression-free survival at 3 years was 25.4% (95% CI, 15.7-36.2) and at 4 years was 18.5% (95% CI, 10.1-28.8 time 0 corresponds to 1 year after starting VEX). A total of 25 patients required a dose reduction, 7% of patients experienced G3 hand and foot syndrome. Metronomic VEX regimen can induce prolonged clinical benefit in MBC. On the basis of this long-term safety evaluation, there is no evidence of specific cumulative or delayed toxicities with metronomic chemotherapy.

Adjuvant treatment for triple negative breast cancer with residual tumor after neo-adjuvant chemotherapy. A single institutional retrospective analysis

Purpose

Incomplete response to neoadjuvant chemotherapy (NACT) in triple negative breast cancer (TNBC) patients is correlated to high risk of relapse. This study aimed to evaluate the role of adjuvant chemotherapy in TNBC with residual tumor after NACT.

Methods

We retrospectively reviewed the outcome of patients with TNBC with residual tumor at surgery after a neoadjuvant treatment, followed by either adjuvant chemotherapy or observation. Primary endpoints were Disease Free Survival (DFS) and Overall Survival (OS).

Results

Between January 2000 and December 2016, 223 patients with early TNBC operated at the European Institute of Oncology were eligible. A total of 83.4 % of patients received adjuvant chemotherapy after surgery. 90 patients received standard dose infusional regimens, while 96 patients (51.6 %) received oral metronomic chemotherapy. Adjusting the analysis by surgical stage and Ki67 value there was a benefit for DFS and OS in favor of the group that received postoperative chemotherapy (DFS-HR 0.58 p = 0.04; OS-HR 0.54, p = 0.02). At a subgroup analysis according to the different adjuvant treatments received, a benefit for metronomic chemotherapy versus no chemotherapy both for DFS (HR 0.46, p = 0.008) and OS (HR 0.45, p = 0.009) was reported.

Conclusion

Our retrospective analysis in a large cohort of TNBC patients with residual disease after NACT confirms the benefit of adding a postoperative treatment to reduce risk of relapse and death. Based on these results, we suggest that the adjuvant therapy based on metronomic cyclophosphamide and methotrexate deserves further investigation in this patients population.

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Triple negative breast cancer is associated with worse prognosis and high rate of relapse.

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Different treatment strategies have been evaluated to manage TNBC disease in any stage.

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Pathological residual disease after a neoadjuvant chemotherapy represents an important prognostic factor.

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Adjuvant treatment strategies in this setting have shown an impact on outcome.

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Metronomic therapy could be a valid and interesting approach in this context.

Estrogen receptor-low breast cancer: Biology chaos and treatment paradox

Hormone receptor testing mainly serves the purpose of guiding treatment choices for breast cancer patients. Patients with estrogen receptor (ER)‐positive breast cancers show significant response to endocrine therapy. However, the methods to define ER status and eligibility for treatment remain controversial. Despite recent guidelines considering staining ≥1% of tumor nuclei by immunohistology as ER‐positive, it has raised concerns on the benefit of endocrine therapy for tumors with ER 1%‐10% expression, termed “ER‐low positive”. This subgroup accounts for 3% to 9% of all patients and is likely to have unique molecular features, and therefore distinct therapeutic response to endocrine therapy compared with ER‐high positive tumors. The latest guidelines did not provide detailed descriptions for those patients, resulting in inconsistent treatment strategies. Consequently, we aimed to resolve this dilemma comprehensively. This review discusses molecular traits and recent ER‐low positive breast cancer innovations, highlighting molecular‐targeted treatment rather than traditional unified endocrine therapy for future basic and clinical research.

Updated Standardized Definitions for Efficacy End Points (STEEP) in Adjuvant Breast Cancer Clinical Trials: STEEP Version 2.0

PURPOSE

The Standardized Definitions for Efficacy End Points (STEEP) criteria, established in 2007, provide standardized definitions of adjuvant breast cancer clinical trial end points. Given the evolution of breast cancer clinical trials and improvements in outcomes, a panel of experts reviewed the STEEP criteria to determine whether modifications are needed.

METHODS

We conducted systematic searches of ClinicalTrials.gov for adjuvant systemic and local-regional therapy trials for breast cancer to investigate if the primary end points reported met STEEP criteria. On the basis of common STEEP deviations, we performed a series of simulations to evaluate the effect of excluding non-breast cancer deaths and new nonbreast primary cancers from the invasive disease-free survival end point.

RESULTS

Among 11 phase III breast cancer trials with primary efficacy end points, three had primary end points that followed STEEP criteria, four used STEEP definitions but not the corresponding end point names, and four used end points that were not included in the original STEEP manuscript. Simulation modeling demonstrated that inclusion of second nonbreast primary cancer can increase the probability of incorrect inferences, can decrease power to detect clinically relevant efficacy effects, and may mask differences in recurrence rates, especially when recurrence rates are low.

CONCLUSION

We recommend an additional end point, invasive breast cancer-free survival, which includes all invasive disease-free survival events except second nonbreast primary cancers. This end point should be considered for trials in which the toxicities of agents are well-known and where the risk of second primary cancer is small. Additionally, we provide end point recommendations for local therapy trials, low-risk populations, noninferiority trials, and trials incorporating patient-reported outcomes.

Metronomic Chemotherapy

Simple Summary

The present article reviews the state of the art of metronomic chemotherapy use to treat the principal types of cancers, namely breast, non-small cell lung cancer and colorectal ones, and of the most recent progresses in understanding the underlying mechanisms of action. Areas of novelty, in terms of new regimens, new types of cancer suitable for Metronomic chemotherapy (mCHT) and the overview of current ongoing trials, along with a critical review of them, are also provided.

Abstract

Metronomic chemotherapy treatment (mCHT) refers to the chronic administration of low doses chemotherapy that can sustain prolonged, and active plasma levels of drugs, producing favorable tolerability and it is a new promising therapeutic approach in solid and in hematologic tumors. mCHT has not only a direct effect on tumor cells, but also an action on cell microenvironment, by inhibiting tumor angiogenesis, or promoting immune response and for these reasons can be considered a multi-target therapy itself. Here we review the state of the art of mCHT use in some classical tumour types, such as breast and no small cell lung cancer (NSCLC), see what is new regarding most recent data in different cancer types, such as glioblastoma (GBL) and acute myeloid leukemia (AML), and new drugs with potential metronomic administration. Finally, a look at the strategic use of mCHT in the context of health emergencies, or in low –and middle-income countries (LMICs), where access to adequate healthcare is often not easy, is mandatory, as we always need to bear in in mind that equity in care must be a compulsory part of our medical work and research.

Metaplastic breast cancer: Prognostic and therapeutic considerations

INTRODUCTION

Metaplastic breast cancer (MBC) is a rare condition of breast tumor with different subtypes, considered a disease with worse prognosis; treatments and survival are often unclear and conflicting.

METHODS

We consecutively collected 153 primary MBCs of different subtypes. Breast surgery, neoadjuvant or adjuvant treatment, clinic-pathological factors, number and type of events during follow-up were considered to evaluate overall survival (OS) and invasive disease-free survival (IDFS).

RESULTS

The majority of MBC was triple-negative (TN) subtype (88.7%), G3 (95.3%), pN0 (70.6%), and with high levels of Ki-67 (93.5%). For OS and IDFS, no significant associations were seen between the different MBC subtypes. The matched triple-negative MBC (TNMBC) and ductal TNBC cohorts had similar prognosis both in terms of OS (p = .411) and IDFS (p = .981). We observed a positive trend for TNMBC patients treated in the adjuvant setting with the cyclofosfamide, methotrexate, 5-fluorouracil protocol for better OS (p = .090) and IDFS (p = .087). A poor or absent response rate was observed in the neoadjuvant setting.

CONCLUSION

Our results demonstrate that metaplastic and ductal breast cancers with TN phenotype are similar in terms of overall and disease-free survival. Metaplastic cancers are poorly responsive to neoadjuvant treatment, and in the absence of novel targeted therapies, surgical treatment remains the first choice.

De-escalating cancer treatments during COVID 19 pandemic: Is metronomic chemotherapy a reasonable option?

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COVID 19 pandemic represents an emergency for public health services.

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The reorganization of the healthcare system has had an important impact on the management of cancer patients.

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Oral treatments and de-escalation strategies are encouraged.

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Oral metronomic chemotherapy could be a reasonable treatment option in some cancer patients subgroups during COVID 19 pandemic.

COVID 19 pandemic represents an emergency for public health services and containment measures to reduce the risk of infection have been promptly activated worldwide.

The healthcare systems reorganization has had a major impact on the management of cancer patients who are considered at high risk of infection.

Recommendations and guidelines on how to manage cancer patients during COVID 19 pandemic have been published. Oral administration of chemotherapy is recommended to limit the access of cancer patients to hospital facilities and in some cases to guarantee the continuum of care.

Low-dose metronomic administration of chemotherapy with different drugs and schedules has emerged in the last years as a possible alternative to conventional chemotherapy, due to its promising tumor control rates and excellent safety profiles. Moreover, given that many metronomic schedules use the oral route administration, it could represent a therapeutic strategy to ensure continuum of cancer care during COVID 19 pandemic.

In this review we have selected all the clinical studies that have used the metronomic strategy, especially with oral drugs, in order to identify the subgroups of cancer patients who can benefit most from a metronomic approach even during COVID 19 pandemic.

Methotrexate inhibits SARS-CoV-2 virus replication "in vitro"

In early 2020 the new respiratory syndrome COVID‐19 (caused by the zoonotic SARS‐CoV‐2 virus) spread like a pandemic, starting from Wuhan, China, causing severe economic depression. Despite some advances in drug treatments of medical complications in the later stages of the disease, the pandemic's death toll is tragic, as no vaccine or specific antiviral treatment is currently available. By using a systems approach, we identify the host‐encoded pathway, which provides ribonucleotides to viral RNA synthesis, as a possible target. We show that methotrexate, an FDA‐approved inhibitor of purine biosynthesis, potently inhibits viral RNA replication, viral protein synthesis, and virus release. The effective antiviral methotrexate concentrations are similar to those used for established human therapies using the same drug. Methotrexate should be most effective in patients at the earliest appearance of symptoms to effectively prevent viral replication, diffusion of the infection, and possibly fatal complications.

The COVID‐19 pandemic caused by the SARS‐CoV‐2 virus is a global public health threat causing over 800000 deaths, millions of infected people, and severe economic depression.

No vaccine or specific antiviral treatments are currently available.

By inhibiting the host‐encoded pathway, which provides ribonucleotides to viral RNA synthesis, the FDA‐approved drug methotrexate efficiently blocks SARS‐CoV‐2 replication.

Metronomic chemotherapy offsets HIFα induction upon maximum-tolerated dose in metastatic cancers

Conventional maximum-tolerated dose (MTD) chemotherapy relies on periodic, massive cancer cell ablation events followed by treatment-free intermissions, stereotypically resulting in resistance, relapse, and mortality. Furthermore, MTD chemotherapy can promote metastatic dissemination via activation of a transcriptional program dependent on hypoxia-inducible factor (HIF)-1α and (HIF)-2α (hereafter referred to as HIFα). Instead, frequent low-dose metronomic (LDM) chemotherapy displays less adverse effects while preserving significant pre-clinical anticancer activity. Consequently, we hereby compared the effect of MTD or LDM chemotherapy upon HIFα in models of advanced, metastatic colon and breast cancer. Our results revealed that LDM chemotherapy could offset paralog-specific, MTD-dependent HIFα induction in colon cancers disseminating to the liver and lungs, while limiting HIFα and hypoxia in breast cancer lung metastases. Moreover, we assessed the translational significance of HIFα activity in colorectal and breast TCGA/microarray data, by developing two compact, 11-gene transcriptomic signatures allowing the stratification/identification of patients likely to benefit from LDM and/or HIFα-targeting therapies. Altogether, these results suggest LDM chemotherapy as a potential maintenance strategy to stave off HIFα induction within the intra-metastatic tumor microenvironment.

Alogliptin attenuates cyclophosphamide-induced nephrotoxicity: a novel therapeutic approach through modulating MAP3K/JNK/SMAD3 signaling cascade

Cyclophosphamide (CP) is widely used as a chemotherapy against various types of cancers. However, CP is accompanied with multiple organ toxicity due to production of reactive oxygen species (ROS), induction of inflammation and consequently apoptosis. Alogliptin (Alo) is a dipeptidyl peptidase 4 (DPP-IV) inhibitor, which is booming as an antidiabetic agent. Interestingly, gliptins are currently studied for their counter-regulatory effects against oxidative stress and inflammation via multiple pathways, among which is the mitogen-activated protein kinase (MAPK)/c-Jun N-terminal kinase (JNK) pathway. This cascade can reduce inflammation via mitigating the activity of mothers against decapentaplegic homolog 3 (SMAD3) and c-Jun. However, Alo effect against CP-induced kidney injury has not been previously elucidated. This tempted us to investigate the possible beneficial effect of Alo against CP-induced kidney injury via modulating the MAP3K/JNK/SMAD3 signaling cascade. Thirty-two male Wistar rats were randomly allocated into four groups. CP-treated group received a single dose of CP (200 mg/kg; i.p.). Alo-treated group received Alo (20 mg/kg/day; p.o.) for 7 days with single CP injection on day 2. Marked decrease in renal injury was observed upon Alo treatment, as evidenced through declined serum kidney function markers, oxidative stress and apoptosis markers, MAP3K expression, phospho (p)-SMAD3, p-JNK, and p-c-Jun levels. These cellular effects were reflected in reduced transforming growth factor beta (TGF-β) and tumor necrosis factor alpha (TNF-α) fibrotic and inflammatory mediators, coinciding with improved histopathological portrait. In conclusion, the current study provides novel application of Alo as a therapeutic modality against CP-induced nephrotoxicity.

Recent clinical evidence on metronomic dosing in controlled clinical trials: a systematic literature review

Introduction: Metronomic dosing is used to give continuous chemotherapy at low doses. The low doses have minimal side effects and may enable cancer treatment to be remodeled toward the management of chronic disease.Methods: We searched PubMed database to obtain relevant clinical trials studying metronomic chemotherapy (MCT). Our main focus was to find controlled phase II and phase III trials.Results: This systematic review summarizes the results of 91 clinical reports focusing on randomized phase II and phase III clinical studies between 2012 and 2018. During that time, nine randomized phase II and 10 randomized phase III studies were published. In the majority of the studies, MCT was well tolerated, and major side effects were rarely seen. Altogether, 4 phase III studies and 4 randomized phase II studies presented positive results and some clinical benefit.Discussion: Most of the studies did not show significantly improved overall survival or progression-free survival. Typically, the metronomic dosing was explored in a maintenance setup and was added to other agents given within normal high doses, whereas no trial was performed challenging metronomic dosing and best supportive care in later treatment lines. Therefore, there is no definite evidence on the efficacy of single metronomic dosing and firm evidence of metronomic dosing is still missing. There is a need for further confirmation of the usefulness of this approach in clinical practice.

Metronomic chemotherapy of cyclophosphamide plus methotrexate for advanced breast cancer: Real-world data analyses and experience of one center

Background

Real‐world data of the CM regimen [cyclophosphamide (CTX) plus methotrexate (MTX)] in metronomic pattern for advanced breast cancer is limited to small‐sample or retrospective studies. This study was aimed to determine the effectiveness and safety of CM regimen in treating advanced breast cancer and to identify which patients are most likely to benefit from metronomic CM regimen.

Methods

Patients with advanced breast cancer who received the metronomic CM regimen at least once between January 2009 and February 2019 in Sun Yat‐sen University Cancer Center were included. Clinicopathological characteristics were collected. Overall survival (OS) and progression‐free survival (PFS) were assessed using Kaplan‐Meier estimates. Characteristics between patients with PFS < 6 months and ≥6 months were compared using the Chi‐square test. Univariate and multivariate Cox regression model was used to estimate the prognostic factors for PFS and OS.

Results

A total of 186 patients were included. The median age and follow‐up were 49 years and 13.3 months, respectively. Over 50% of the patients were estrogen receptor/progesterone receptor‐positive, and 60.8% had been heavily treated (≥3 lines). The objective response rate was 3.8%, the disease control rate at 12 weeks was 41.4%, and the clinical benefit rate at 24 weeks was 31.2% (58/186). The median PFS was 4.0 months [95% confidence interval (CI): 3.6‐4.7 months], the median duration of clinical benefit was 9.5 months (95% CI: 8.2‐10.8 months), and the median OS was 26.8 months (95% CI: 20.9‐37.7 months). Multivariate analysis for PFS revealed the CM regimen as maintenance therapy and no liver metastasis as favorable prognostic factors. Furthermore, patients without liver metastasis were more likely to have a PFS over 6 months than those with liver involvement (P = 0.022). Liver, lymph node, and brain metastases were unfavorable prognostic factors for OS. The CM regimen was well‐tolerated without newly reported adverse events.

Conclusions

The CM regimen was effective in selected patients. In clinical practice, it would be better used as maintenance therapy and in patients without liver metastasis. Further follow‐up investigation should be performed to examine its effect when used in combination with other treatments and determine predictive biomarkers.

Suppressive impact of metronomic chemotherapy using UFT and/or cyclophosphamide on mediators of breast cancer dissemination and invasion

Metronomic chemotherapy using the 5-FU prodrug uracil-tegafur (UFT) and cyclophosphamide (CTX) was previously shown to only modestly delay primary tumor growth, but nevertheless markedly suppressed the development of micro-metastasis in an orthotopic breast cancer xenograft model, using the metastatic variant of the MDA-MB-231 cell line, 231/LM2-4. Furthermore, a remarkable prolongation of survival, with no toxicity, was observed in a model of postsurgical advanced metastatic disease. A question that has remained unanswered is the seemingly selective anti-metastatic mechanisms of action responsible for this treatment. We assessed the in vivo effect of metronomic UFT, CTX or their combination, on vascular density, collagen deposition and c-Met (cell mediators or modulators of tumor cell invasion or dissemination) via histochemistry/immunohistochemistry of primary tumor sections. We also assessed the effect of continuous exposure to low and non-toxic doses of active drug metabolites 5-fluorouracil (5-FU), 4-hydroperoxycyclophosphamide (4-HC) or their combination, on 231/LM2-4 cell invasiveness in vitro. In the in vivo studies, a significant reduction in vascular density and p-Met[Y1003] levels was associated with UFT+CTX treatment. All treatments reduced intratumoral collagen deposition. In the in vitro studies, a significant reduction of collagen IV invasion by all treatments was observed. The 3D structures formed by 231/LM2-4 on Matrigel showed a predominantly Mass phenotype under treated conditions and Stellate phenotype in untreated cultures. Taken together, the results suggest the low-dose metronomic chemotherapy regimens tested can suppress several mediators of tumor invasiveness highlighting a new perspective for the anti-metastatic efficacy of metronomic chemotherapy.

Early triple negative breast cancer: Are we getting better outcomes? A retrospective analysis from a single institution

Overall survival (OS), disease-free survival (DFS), and distant recurrence-free interval (DRFI) were evaluated from 169 patients diagnosed with early triple negative breast cancer. Overall, 5 and 10 years OS, DFS, and DRFI were 77% and 65%; 60% and 46%; and 74% and 73%, respectively. Forty-seven patients did not receive chemotherapy. A separate analysis was performed excluding those patients. In this subgroup, 5- and 10-year OS, DFS, and DRFI were 86% and 77%; 68% and 54%, 77% both at 5 and 10 years. Prognosis is better than previously described; adjuvant chemotherapy should be offered to fit elderly patients if clinically warranted.

Treating advanced breast cancer with metronomic chemotherapy: what is known, what is new and what is the future?

The prognosis for patients with locally advanced or metastatic breast cancer (mBC) remains poor, with a median survival of 2–4 years. About 10% of newly diagnosed breast cancer patients present with metastatic disease, and 30%–50% of those diagnosed at earlier stages will subsequently progress to mBC. In terms of ongoing management for advanced/metastatic breast cancer after failure of hormonal therapy, there is a high medical need for new treatment options that prolong the interval to the start of intensive cytotoxic therapy, which is often associated with potentially serious side effects and reduced quality of life. Oral chemotherapeutic agents such as capecitabine and vinorelbine have demonstrated efficacy in patients with mBC, with prolonged disease control and good tolerability. Use of oral chemotherapy reduces the time and cost associated with treatment and is often more acceptable to patients than intravenous drug delivery. Metronomic administration of oral chemotherapy is therefore a promising treatment strategy for some patients with mBC and inhibits tumor progression via multiple mechanisms of action. Ongoing clinical trials are investigating metronomic chemotherapy regimens as a strategy to prolong disease control with favorable tolerability. This article provides an overview of metronomic chemotherapy treatment options in mBC, with perspectives on this therapy from a panel of experts.

Explorative Analysis of Low-Dose Metronomic Chemotherapy with Cyclophosphamide and Methotrexate in a Cohort of Metastatic Breast Cancer Patients

Background

Low-dose metronomic chemotherapy (LDMC) is increasingly used in metastatic breast cancer (MBC). In this retrospective analysis, we examined the therapeutic effects and side effects of LDMC in a cohort of MBC patients.

Methods

Patients with MBC were included when LDMC with oral cyclophosphamide (CTX) and methotrexate (MTX) was administered between 2009 and 2015. The primary endpoint was disease control rate (DCR) ≥ 24 weeks after the start of LDMC. Secondary endpoints were duration of progression-free survival (PFS), rates of discontinuation due to side effects, and DCR with regard to subgroups.

Results

Retrospective data of 35 patients were available for this analysis. 31% patients achieved DCR. The median PFS was 12 weeks. 9% of patients discontinued LDMC due to adverse events. DCR was 37% in the first 2 lines and 25% in further lines of therapy. 22% of patients with multiple metastases and 35% with ≤2 different metastatic sites achieved DCR. DCR was achieved in 33% of hormone receptor(HR)-positive patients and 27% of HR-negative patients.

Conclusion

The DCR of 31% is in line with the results of previous phase II studies. LDMC was well tolerated. Subgroup analysis was not able to identify a group in which LDMC was more efficient.

Metronomic Chemotherapy for First-Line Treatment of Metastatic Triple-Negative Breast Cancer: A Phase II Trial

Background

Few data are available on the benefit of metronomic cyclophosphamide, capecitabine, and vinorelbine as first-line therapy in patients with metastatic triple-negative breast cancer.

Methods

This phase II study assessed the safety and efficacy of metronomic oral chemotherapy with vinorelbine 40 mg orally 3 times a week, cyclophosphamide 50 mg daily, and capecitabine 500 mg 3 times a day (VEX regimen) in untreated metastatic triple-negative breast cancer patients. The biopsy of the metastatic site had to be triple-negative, independent of the hormone receptor expression of the primary tumor. The primary endpoint was time to progression (TTP). Secondary endpoints included assessment of safety and clinical benefit (objective response rate plus stable disease rate at ≥24 weeks).

Results

25 patients were included, and 22 were evaluable for both efficacy and toxicities (median age, 66 years). Median TTP was 6.4 months (95% confidence interval 3.6-12.6). The most common grade 1-2 toxicities were nausea, diarrhea, leuko-/neutropenia, and reversible liver enzyme alteration. Grade 3 events included hand and foot syndrome (9%).

Conclusion

The VEX regimen demonstrated activity and was relatively well tolerated when given as first-line therapy in selected metastatic breast cancer patients with triple-negative disease.

Mutational analysis of triple-negative breast cancers within the International Breast Cancer Study Group (IBCSG) Trial 22-00

PURPOSE

We investigated the occurrence and the prognostic and predictive relationship of a selected number of somatic mutations in triple-negative breast cancer (TNBC) patients having known clinical outcomes treated within the IBCSG Trial 22-00.

METHODS

A matched case-control sampling selected patients enrolled in the IBCSG Trial 22-00 who had TNBC tumors, based on local assessment. Cases had invasive breast cancer recurrence (at local, regional, or distant site) according to the protocol definition. Matched controls had not recurred. Mutational analysis was performed with OncoCarta panel v1.0 using Mass Array System. The panel includes 19 genes belonging to different functional pathways as PI3K pathway, receptor tyrosine kinase, and cell cycle-metabolic group. Conditional logistic regression assessed the association of mutation status with breast cancer recurrence.

RESULTS

Mutation assessment was successful for 135 patients (49 cases, 86 controls). A total of 37 (27.4%) of the 135 patients had at least one mutation in the selected genes. PIK3CA was the most common mutated gene (18/135; 13.3%), followed by BRAF, KIT and PDGFRA (each 4/135, 3.0%) and AKT1 (3/135; 2.2%). TNBC patients with at least one mutation had increased odds of recurrence compared with those with wild-type tumors (odds ratio (OR) 2.28; 95% CI 0.88-5.92), though this difference was not statistically significant (p = 0.09). We found no evidence that these mutations were predictive for the value of maintenance metronomic chemotherapy.

CONCLUSIONS

Mutations in the tested oncogenes were not associated with breast cancer recurrence in this TNBC subset of patients. The question of whether any of these mutated genes (e.g., PIK3CA) may represent a useful therapeutic target in TNBC may be answered by ongoing clinical trials and/or larger dataset analysis.

Contralateral breast cancers: Independent cancers or metastases?

A cancer in the contralateral breast in a woman with a previous or synchronous breast cancer is typically considered to be an independent primary tumor. Emerging evidence suggests that in a small subset of these cases the second tumor represents a metastasis. We sought to investigate the issue using massively parallel sequencing targeting 254 genes recurrently mutated in breast cancer. We examined the tumor archives at Memorial Sloan Kettering Cancer Center for the period 1995-2006 to identify cases of contralateral breast cancer where surgery for both tumors was performed at the Center. We report results from 49 patients successfully analyzed by a targeted massively parallel sequencing assay. Somatic mutations and copy number alterations were defined by state-of-the-art algorithms. Clonal relatedness was evaluated by statistical tests specifically designed for this purpose. We found evidence that the tumors in contralateral breasts were clonally related in three cases (6%) on the basis of matching mutations at codons where somatic mutations are rare. Clinical data and the presence of similar patterns of gene copy number alterations were consistent with metastasis for all three cases. In three additional cases, there was a solitary matching mutation at a common PIK3CA locus. The results suggest that a subset of contralateral breast cancers represent metastases rather than independent primary tumors. Massively parallel sequencing analysis can provide important evidence to clarify the diagnosis. However, given the inter-tumor mutational heterogeneity in breast cancer, sufficiently large gene panels need to be employed to define clonality convincingly in all cases.

Role of regulatory T cells in irinotecan-induced intestinal mucositis

Intestinal mucositis (IM) is a common side effect of irinotecan-based chemotherapy. The involvement of inflammatory mediators, such as TNF-α, IL1-β, IL-18 and IL-33, has been demonstrated. However, the role of adaptive immune system cells, whose activation is partially regulated by these cytokines, is yet unknown. Thus, we investigated the role of regulatory T cells (Tregs) in irinotecan-induced IM. C57BL/6 mice were injected with saline or irinotecan (75mgkg^-1, i.p.), once a day for 4days, and euthanized at day 1, 3, 5 or 7 following the first dose of irinotecan. For Treg depletion, the mice were pretreated with a low single dose of cyclophosphamide (100mgkg^-1, i.p). Intestinal lamina propria lymphocytes were harvested and purified by Percoll gradient. Treg and Th17 cells were identified by flow cytometry. Blood leukocyte count was obtained and ileum samples were collected for histopathological analysis and myeloperoxidase assay. IM caused an accumulation of Tregs and Th17 cells over time. Treg depletion exacerbated intestinal damage, diarrhea, neutrophil infiltration and animal mortality, despite a reduction in Th17 cell number. The frequency of other Th cells increased and was positively correlated with neutrophil infiltration. Tregs showed a negative correlation with neutrophils and the frequency of non-regulatory Th cells. In conclusion, Tregs are important in the control of intestinal damage induced by irinotecan, and their depletion showed a deleterious effect on IM. Activation of these cells appears to be a compensatory mechanism for intestinal inflammation.

Metronomic chemotherapy for non-metastatic triple negative breast cancer: Selection is the key

Triple negative breast cancer (TNBC) accounts for 15%-20% of all breast cancer, and is still defined as what it is not. Currently, TNBC is the only type of breast cancer for which there are no approved targeted therapies and maximum tolerated dose chemotherapy with taxanes and anthracycline-containing regimens is still the standard of care in both the neoadjuvant and adjuvant settings. In the last years, metronomic chemotherapy (MC) is being explored as an alternative to improve outcomes in TNBC. In the neoadjuvant setting, purely metronomic and hybrid approaches have been developed with the objective of increasing complete pathologic response (pCR) and prolonging disease free survival. These regimens proved to be very effective achieving pCR rates between 47%-60%, but at the cost of great toxicity. In the adjuvant setting, MC is used to intensify adjuvant chemotherapy and, more promisingly, as maintenance therapy for high-risk patients, especially those with no pCR after neoadjuvant chemotherapy. Considering the dismal prognosis of TNBC, any strategy that potentially improves outcomes, specially being the oral agents broadly available and inexpensive, should be considered and certainly warrants further exploration. Finally, the benefit of MC needs to be validated in properly designed clinical trials were the selection of the population is the key.

Metronomic Chemotherapy in Triple-Negative Metastatic Breast Cancer: The Future Is Now?

Triple-negative breast cancer (TNBC) shows a very bad prognosis, even in early stages of disease. Metronomic chemotherapy refers to the minimum biologically effective dose of a chemotherapy agent given as a continuous dosing regimen with no prolonged drug-free breaks that leads to antitumor activity. In the present article, we review preclinical and clinical data of metronomic administration of chemotherapy agents with or without biological agents in TNBC cell lines and patients, contextually reporting data from the VICTOR-2 study in the subgroup of patients with TNBC, in order to stimulate new ideas for the design of clinical trials in this subset of patients.

Tumour-infiltrating lymphocytes (TILs)-related genomic signature predicts chemotherapy response in breast cancer

PURPOSE

The present study evaluated whether morphological-measured stromal and intra-tumour tumour-infiltrating lymphocytes (TILs) levels were associated with gene expression profiles, and whether TILs-associated genomic signature (GS) could be used to predict clinical outcomes and response to therapies in several breast cancer subtypes.

METHODS

We retrospectively evaluated haematoxylin eosin (HE)-TILs levels and gene expression profiling data from 40 patients with primary breast cancer and extracted the 22 overexpressed genes in cases with high TILs scores as the TILs-GS. The TILs-GS were compared with breast cancer subtype and were evaluated predictive values for prognosis and response to therapies.

RESULTS

Higher TILs-GS expressions were observed for triple-negative and human epidermal growth factor receptor 2 (HER2) positive (+) breast cancers, compared to the luminal types (P < 0.001). With the exception of HER2+, the TILs-GS had no prognostic value in subtypes of breast cancers. The Wilcoxon test revealed significantly different TILs-GS levels between the cases with pathological complete response (pCR) and residual disease after anthracycline and taxane-based neoadjuvant chemotherapy, with the exception of the luminal-low proliferation subtype. In the multivariate analysis, pCR was independently associated with smaller tumour size, higher histological grade, ER negativity, HER2 positivity and higher TILs-GS scores (OR 2.02, 95% CI 1.30-3.14, P = 0.025).

CONCLUSIONS

TILs-GS was associated with stromal and intra-tumour TILs levels, as evaluated using HE, which predicted prognosis and chemotherapy response in several breast cancer subtypes. Further studies are needed to perform stratification according to TILs-GS levels and the conventional breast cancer subtypes.

Effect of Axillary Dissection vs No Axillary Dissection on 10-Year Overall Survival Among Women With Invasive Breast Cancer and Sentinel Node Metastasis: The ACOSOG Z0011 (Alliance) Randomized Clinical Trial

IMPORTANCE

The results of the American College of Surgeons Oncology Group Z0011 (ACOSOG Z0011) trial were first reported in 2005 with a median follow-up of 6.3 years. Longer follow-up was necessary because the majority of the patients had estrogen receptor-positive tumors that may recur later in the disease course (the ACOSOG is now part of the Alliance for Clinical Trials in Oncology).

OBJECTIVE

To determine whether the 10-year overall survival of patients with sentinel lymph node metastases treated with breast-conserving therapy and sentinel lymph node dissection (SLND) alone without axillary lymph node dissection (ALND) is noninferior to that of women treated with axillary dissection.

DESIGN, SETTING, AND PARTICIPANTS

The ACOSOG Z0011 phase 3 randomized clinical trial enrolled patients from May 1999 to December 2004 at 115 sites (both academic and community medical centers). The last date of follow-up was September 29, 2015, in the ACOSOG Z0011 (Alliance) trial. Eligible patients were women with clinical T1 or T2 invasive breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases.

INTERVENTIONS

All patients had planned lumpectomy, planned tangential whole-breast irradiation, and adjuvant systemic therapy. Third-field radiation was prohibited.

MAIN OUTCOMES AND MEASURES

The primary outcome was overall survival with a noninferiority hazard ratio (HR) margin of 1.3. The secondary outcome was disease-free survival.

RESULTS

Among 891 women who were randomized (median age, 55 years), 856 (96%) completed the trial (446 in the SLND alone group and 445 in the ALND group). At a median follow-up of 9.3 years (interquartile range, 6.93-10.34 years), the 10-year overall survival was 86.3% in the SLND alone group and 83.6% in the ALND group (HR, 0.85 [1-sided 95% CI, 0-1.16]; noninferiority P = .02). The 10-year disease-free survival was 80.2% in the SLND alone group and 78.2% in the ALND group (HR, 0.85 [95% CI, 0.62-1.17]; P = .32). Between year 5 and year 10, 1 regional recurrence was seen in the SLND alone group vs none in the ALND group. Ten-year regional recurrence did not differ significantly between the 2 groups.

CONCLUSIONS AND RELEVANCE

Among women with T1 or T2 invasive primary breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases, 10-year overall survival for patients treated with sentinel lymph node dissection alone was noninferior to overall survival for those treated with axillary lymph node dissection. These findings do not support routine use of axillary lymph node dissection in this patient population based on 10-year outcomes.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00003855.

Extended Adjuvant Chemotherapy in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) represents a heterogeneous breast cancer subtype with a poor prognosis. The optimal adjuvant chemotherapy regimen is still unknown. Although numerous large randomized trials have established the benefit of adjuvant anthracyclines and/or taxanes in TNBC, there is no preferred regimen for these patients. There is currently no guideline. Moreover, without knowing the optimal treatment backbone, it will not be possible to evaluate whether adding agents such as platinum or other novel therapies is beneficial for TNBC patients. Furthermore, the best duration of adjuvant treatment in TNBC is still unknown. This review will focus on results of clinical trials that analyzed the benefits of extending the duration of adjuvant treatment in TNBCs with maintenance treatments. We will further discuss promising results in favor of other new agents including capecitabine, metronomic treatment, and biological drugs.

Molecular alterations in triple-negative breast cancer-the road to new treatment strategies

Triple-negative breast cancer is a heterogeneous disease and specific therapies have not been available for a long time. Therefore, conventional chemotherapy is still considered the clinical state of the art. Different subgroups of triple-negative breast cancer have been identified on the basis of protein expression, mRNA signatures, and genomic alterations. Important elements of triple-negative breast cancer biology include high proliferative activity, an increased immunological infiltrate, a basal-like and a mesenchymal phenotype, and deficiency in homologous recombination, which is in part associated with loss of BRCA1 or BRCA2 function. A minority of triple-negative tumours express luminal markers, such as androgen receptors, and have a lower proliferative activity. These biological subgroups are overlapping and currently cannot be combined into a unified model of triple-negative breast cancer biology. Nevertheless, the molecular analysis of this disease has identified potential options for targeted therapeutic intervention. This has led to promising clinical strategies, including modified chemotherapy approaches targeting the DNA damage response, angiogenesis inhibitors, immune checkpoint inhibitors, or even anti-androgens, all of which are being evaluated in phase 1-3 clinical studies. This Series paper focuses on the most relevant clinical questions, summarises the results of recent clinical trials, and gives an overview of ongoing studies and trial concepts that will lead to a more refined therapy for this tumour type.

Whether low-dose metronomic oral cyclophosphamide improves the response to docetaxel in first-line treatment of non-triple-negative metastatic breast cancer

Oral metronomic chemotherapy may target tumor cells indirectly via antiangiogenic activity, restoration of anticancer immune response, or induction of tumor dormancy. We initiated the single-center, randomized, open-label, phase II study to determine whether the addition of metronomic cyclophosphamide to docetaxel (T) (w/o trastuzumab) improves overall response rate (ORR) as first-line treatment among patients with non-triple-negative metastatic breast cancer (MBC). Eligible patients with previously untreated non-triple-negative MBC were randomly assigned (1:1) to receive 3-weekly cycles of Metro-TC (T 75mg/m², d1 plus oral cyclophosphamide 50 mg daily) or T alone. All patients received treatment until disease progression, unacceptable toxicity, or withdrawal of consent. The primary endpoint was ORR. Finally, 35 patients were randomized to Metro-TC group while 31 to T group. Median treatment cycles of T for both groups were 8. ORR was not improved by addition of metronomic cyclophosphamide to T (71.4% vs. 51.6%; P = 0.09). There was no statistically significant difference with regard to progression free survival (median 18.5 vs. 11.7 months; P = 0.07) or overall survival (median 33.7 vs. 33.6 months; P = 0.84) between the two group. Grade 3/4 adverse events (eg. neutropenia [100% vs. 100%], febrile neutropenia [29% vs. 29%], and neurotoxicity [6% vs. 3%]) were also comparable. There were no treatment-related deaths. We conclude that concomitant administration of metronomic cyclophosphamide and T does not appear to be a significantly active schedule for first-line treatment of non-triple-negative MBC.

Circulating tumor cells: what we know, what do we want to know about them and are they ready to be used in clinics?

Circulating tumor cells (CTC) present in peripheral blood are assigned precursors of advanced tumor disease. Simplicity of blood withdrawal procedure adds practically an unlimited possibility of the CTC-monitoring and the advantages of the repeated biopsies over time. CTC got prognostic, predictive and diagnostic status with the technologic advance. Although the clinical utility of CTC has reached the high evidence, the significance of CTC testing was presented in the treatment strategy mostly with palliative intention. We report on the experiences with the CTC-testing in the CLIA-like laboratory working with the size-based CTC separation and in vitro culture. The data is presented in the form of case reports in patients with breast (BC), colorectal (CRC), prostate (PC) and lung cancer (NSCLC) to support the clinical utility of CTC during the neoadjuvant, adjuvant and palliative treatment. The presented findings support the evidence for liquid biopsy clinical implementation and enhance the ability of malignant disease monitoring and the treatment efficacy prediction.

Zoledronic acid inhibits NFAT and IL-2 signaling pathways in regulatory T cells and diminishes their suppressive function in patients with metastatic cancer

Regulatory T cells (Treg) suppress anti-tumor immune responses and their infiltration in the tumor microenvironment is associated with inferior prognosis in cancer patients. Thus, in order to enhance anti-tumor immune responses, selective depletion of Treg is highly desired. We found that treatment with zoledronic acid (ZA) resulted in a selective decrease in the frequency of Treg that was associated with a significant increase in proliferation of T cells and natural killer (NK) cells in peripheral blood of patients with metastatic cancer. In vitro, genome-wide transcriptomic analysis revealed alterations in calcium signaling pathways in Treg following treatment with ZA. Furthermore, co-localization of the nuclear factor of activated T cells (NFAT) and forkhead box P3 (FOXP3) was significantly reduced in Treg upon ZA-treatment. Consequently, reduced expression levels of CD25, STAT5 and TGFβ were observed. Functionally, ZA-treated Treg had reduced capacity to suppress T and NK cell proliferation and anti-tumor responses compared with untreated Treg in vitro. Treatment with ZA to selectively inhibit essential signaling pathways in Treg resulting in reduced capacity to suppress effector T and NK cell responses represents a novel approach to inhibit Treg activity in patients with cancer.

Unfavorable prognostic role of tumor-infiltrating lymphocytes in hormone-receptor positive, HER2 negative metastatic breast cancer treated with metronomic chemotherapy

BACKGROUND

High levels of tumor-infiltrating lymphocytes (TILs) in primary triple negative and HER2-positive breast cancer (BC) have been associated with an improved patients' outcome. The role of TILs in Luminal (hormone receptor positive and HER2 negative) tumors remains to be elucidated. Moreover, the association between TILs and prognosis in the metastatic setting is still unknown.

PATIENTS AND METHODS

We evaluated the relationship between TILs and time to progression (TTP) in metastatic BC patients enrolled in a prospective phase II trial of metronomic chemotherapy, that used cyclophosphamide 50 mg daily, capecitabine 500 mg thrice daily and vinorelbine 40 mg orally three times a week (VEX combination).

RESULTS

Of the 108 ER + BC patients enrolled in the VEX trial, 92 (85%) had sufficient tumor tissue and were assessed for TILs in H&E stained slides. TILs were evaluated in 38 primary BC samples and 54 metastatic sites. High (≥10%) TILs levels were significantly correlated with high Ki-67 labeling index. At multivariable analysis, each 10% increase in TILs strongly predicted a worse TTP (HR: 1.27, p = 0.008). VEX trial patients, categorized by a 3 tiers system (0-4%, 5-9% and >10% TILs) showed significantly different progression free survival curves (p = 0.011).

CONCLUSIONS

High TILs levels are significantly associated with a worse TTP in Luminal metastatic BC patients treated by metronomic chemotherapy. Our data confirm the reliability of TILs as a biomarker in the BC metastatic setting. The putative unfavorable prognostic role of TILs in Luminal BC patients might have clinical utility if validated by further studies.