A comparison of toxicity profiles between the lower and standard dose capecitabine in breast cancer: a systematic review and meta-analysis

Feasibility and Tolerability of Adjuvant Capecitabine-Based Chemoradiation in Patients With Breast Cancer and Residual Disease After Neoadjuvant Chemotherapy: A Prospective Clinical Trial

PURPOSE

Addition of adjuvant capecitabine improves overall survival for patients with breast cancer lacking pathologic complete response to standard-of-care neoadjuvant chemotherapy. Combining radiosensitizing capecitabine concurrent with radiation may further improve disease control, although the feasibility and tolerability of chemoradiation in this setting is unknown. This study aimed to determine the feasibility of this combination. Secondary objectives included the effect of chemoradiation on physician-reported toxicity, patient-reported skin dermatitis, and patient-reported quality of life compared with patients with breast cancer treated with adjuvant radiation.

METHODS AND MATERIALS

Twenty patients with residual disease following standard neoadjuvant chemotherapy were enrolled in a prospective single-arm trial and treated with adjuvant capecitabine-based chemoradiation. Feasibility was defined as ≥75% of patients completing chemoradiation as planned. Toxicity was assessed using Common Terminology Criteria for Adverse Events version 5.0 and the patient-reported radiation-induced skin reaction scale. Quality of life was measured using the RAND Short-Form 36-Item Health Survey.

RESULTS

Eighteen patients (90%) completed chemoradiation without interruption or dose reduction. The incidence of grade ≥3 radiation dermatitis was 5% (1 of 20 patients). Patient-reported radiation dermatitis did not show a clinically meaningful difference following chemoradiation (mean increase, 55 points) compared with published reports of patients with breast cancer treated with adjuvant radiation alone (mean increase, 47 points). On the other hand, patient-reported quality of life demonstrated a clinically meaningful decline at the end of chemoradiation (mean, 46; SD, 7) compared with the reference population of patients treated with adjuvant radiation alone (mean, 50; SD, 6).

CONCLUSIONS

Adjuvant chemoradiation with capecitabine is feasible and tolerable in patients with breast cancer. Although current studies using adjuvant capecitabine for residual disease following neoadjuvant chemotherapy have specified sequential treatment of capecitabine and radiation, these results support the conduct of randomized trials in this setting to investigate the efficacy of concurrent radiation with capecitabine and provide patient-reported toxicity estimates for trial design.

Testing Adaptive Therapy Protocols Using Gemcitabine and Capecitabine in a Preclinical Model of Endocrine-Resistant Breast Cancer

Adaptive therapy, an ecologically inspired approach to cancer treatment, aims to overcome resistance and reduce toxicity by leveraging competitive interactions between drug-sensitive and drug-resistant subclones, prioritizing patient survival and quality of life instead of killing the maximum number of cancer cells. In preparation for a clinical trial, we used endocrine-resistant MCF7 breast cancer to stimulate second-line therapy and tested adaptive therapy using capecitabine, gemcitabine, or their combination in a mouse xenograft model. Dose modulation adaptive therapy with capecitabine alone increased survival time relative to MTD but not statistically significantly (HR = 0.22, 95% CI = 0.043-1.1, p = 0.065). However, when we alternated the drugs in both dose modulation (HR = 0.11, 95% CI = 0.024-0.55, p = 0.007) and intermittent adaptive therapies, the survival time was significantly increased compared to high-dose combination therapy (HR = 0.07, 95% CI = 0.013-0.42, p = 0.003). Overall, the survival time increased with reduced dose for both single drugs (p < 0.01) and combined drugs (p < 0.001), resulting in tumors with fewer proliferation cells (p = 0.0026) and more apoptotic cells (p = 0.045) compared to high-dose therapy. Adaptive therapy favors slower-growing tumors and shows promise in two-drug alternating regimens instead of being combined.

Genetic variants and enzyme activity in citidin deaminase: Relationship with capecitabine toxicity and recommendation for dose adjustment

OBJECTIVE

Capecitabine, an antineoplastic drug used in the treatment of breast and colon cancer, can cause severe, even fatal toxicity in some patients. The interindividual variability of this toxicity is largely due to genetic variations in target genes and enzymes of metabolism of this drug, such as thymidylate synthase and dihydropyrimidine dehydrogenase. The enzyme cytidine deaminase (CDA), involved in the activation of capecitabine, also has several variants associated with an increased risk of toxicity to treatment, although its role as a biomarker is not yet clearly defined. Therefore, our main objective is to study the association between the presence of genetic variants in CDA gen, CDA enzymatic activity and the development of severe toxicity in patients treated with capecitabine whose initial dose was adjusted based on the genetic profile of the dihydropyrimidine dehydrogenase gen (DPYD).

METHOD

Prospective multicenter observational cohort study, focused on the analysis of the genotype-phenotype association of the CDA enzyme. After the experimental phase, an algorithm will be developed to determine the dose adjustment needed to reduce the risk of treatment toxicity according to CDA genotype, developing a clinical guide for capecitabine dosing according to genetic variants in DPYD and CDA. Based on this guide, a Bioinformatics Tool will be created to generate the pharmacotherapeutic report automatically, facilitating the implementation of pharmacogenetic advice in clinical practice. This tool will be a great support in making pharmacotherapeutic decisions based on the patient's genetic profile, incorporating precision medicine into clinical routine. Once the usefulness of this tool has been validated, it will be offered free of charge to facilitate the implementation of pharmacogenetics in hospital centers and equitably benefit all patients on capecitabine treatment.

[Translated article] Genetic variants and enzyme activity in citidin deaminase: Relationship with capecitabine toxicity and recommendation for dose adjustment

OBJECTIVE

Capecitabine, an antineoplastic drug used in the treatment of breast and colon cancer, can cause severe, even fatal toxicity in some patients. The interindividual variability of this toxicity is largely due to genetic variations in target genes and enzymes of metabolism of this drug, such as Thymidylate Synthase (TS) and Dihydropyrimidine Dehydrogenase (DPD). The enzyme Cytidine Deaminase (CDA), involved in the activation of capecitabine, also has several variants associated with an increased risk of toxicity to treatment, although its role as a biomarker is not yet clearly defined. Therefore, our main objective is to study the association between the presence of genetic variants in CDA gen, CDA enzymatic activity and the development of severe toxicity in patients treated with capecitabine whose initial dose was adjusted based on the genetic profile of the DPD gen (DPYD).

METHOD

Prospective multicenter observational cohort study, focused on the analysis of the genotype-phenotype association of the CDA enzyme. After the experimental phase, an algorithm will be developed to determine the dose adjustment needed to reduce the risk of treatment toxicity according to CDA genotype, developing a Clinical Guide for capecitabine dosing according to genetic variants in DPYD and CDA. Based on this guide, a Bioinformatics Tool will be created to generate the pharmacotherapeutic report automatically, facilitating the implementation of pharmacogenetic advice in clinical practice. This tool will be a great support in making pharmacotherapeutic decisions based on the patient's genetic profile, incorporating precision medicine into clinical routine. Once the usefulness of this tool has been validated, it will be offered free of charge to facilitate the implementation of pharmacogenetics in hospital centers and equitably benefit all patients on capecitabine treatment.

Antitumor activity of lurbinectedin in combination with oral capecitabine in patients with metastatic breast cancer

BACKGROUND

Preclinical studies showed a synergistic effect for 5-fluorouracil and lurbinectedin against solid tumors. This phase I trial evaluated a combination of capecitabine plus lurbinectedin in patients with selected advanced solid tumors. Results in patients with relapsed metastatic breast cancer (MBC) are described.

PATIENTS AND METHODS

Patients received capecitabine daily on day (D)1-D14 combined with lurbinectedin on D1, D8 or D1 every 3 weeks (q3w) intravenously, following a standard 3 + 3 escalation design and expansion at the recommended dose (RD).

RESULTS

Of the 81 enrolled patients, 28 had relapsed MBC: 20 with hormone receptor (HR)-positive tumors and 8 with triple-negative tumors; 3 treated in the D1,D8 schedule and 25 in the D1 schedule. The RD was capecitabine 1650 mg/m² daily on D1-D14 plus lurbinectedin 2.2 mg/m² on D1 q3w. Sixteen confirmed responses and two prolonged disease stabilizations (≥6 months) were observed [overall response rate (ORR)/clinical benefit rate (CBR) = 57%/64% at all dose levels; 47%/60% at the RD]. Twelve responses and both prolonged stabilizations occurred in HR-positive tumors (ORR/CBR = 60%/70% at all dose levels, 56%/78% at the RD). Four responses were found in triple-negative tumors (ORR and CBR = 50% at all dose levels; 33% at the RD). Myelotoxicity was reversible and manageable at the RD; most non-hematological toxicities were mild/moderate. No episodes of febrile neutropenia or severe palmar-plantar erythrodysesthesia syndrome occurred. No major pharmacokinetic drug-drug interaction was found between lurbinectedin, capecitabine or capecitabine metabolites.

CONCLUSIONS

The capecitabine/lurbinectedin combination showed encouraging clinical activity in relapsed MBC, especially in HR-positive tumors. Toxicity was manageable at the RD. Further development is warranted in relapsed MBC.

Oral Oncolytics: Using Remote Technology to Improve Access, Operational Efficiency, and Satisfaction

Oncology care management via oral oncolytic therapy requires frequent laboratory monitoring for potential toxicities. A lag in these processes can result in treatment delays and care team dissatisfaction. A nurse-led quality improvement project was implemented to streamline processes, clearly define job tasks, and introduce a remote patient-reported symptom monitoring application to improve patient safety, access, operational productivity, and care team satisfaction. Project results included eliminating paper fax distribution, a 97% decrease in time required to process faxed remote laboratory results, and a 78% reduction in mouse clicks to complete laboratory orders and patient correspondence.

Capecitabine-induced leukoencephalopathy in a patient with triple-negative breast cancer: A case report and review of the literature

INTRODUCTION

Capecitabine is an orally administered prodrug that converts preferentially to 5-fluorouracil within tumors, resulting in enhanced concentrations of 5-fluorouracil in tumor tissue. The use of capecitabine has shown efficacy in the metastatic setting for breast cancer, and more recently, efficacy as adjuvant therapy for triple-negative breast cancer (TNBC). Capecitabine has been shown to be well tolerated with minimal side effects, but the incidence of leukoencephalopathy is rare with a risk of less than one percent.

CASE REPORT

We report on a 34-year-old female patient with left TNBC, moderately differentiated, stage IIB that experienced symptoms of neurotoxicity following initiation of adjuvant chemotherapy with capecitabine.

MANAGEMENT AND OUTCOME

Naranjo Algorithm Assessment score of nine indicated patient had drug-induced leukoencephalopathy leading to discontinuation of capecitabine and resolution of the neurotoxicity symptoms.

DISCUSSION

Early detection of capecitabine-induced neurotoxicity by magnetic resonance imaging is crucial as symptoms may be reversible to the condition that capecitabine is immediately discontinued.

Comparative study of low dose of capecitabine versus standard dose in metastatic breast cancer: Efficacy and safety

Background

A lower dose of capecitabine revealed better toxicity profiles and comparable efficacy in treatment of metastatic breast cancer (MBC). We aimed to evaluate the efficacy and toxicity of lower dose of capecitabine in comparison with the standard dose.

Patients and methods

Patients were enrolled in two groups. Group 1 included 21 patients who received the standard dose of capecitabine (1250 mg/m2 twice daily [BID] for 14 days), while the patients in group 2 (19 patients) received lower dose of capecitabine (850 mg/m2 BID for 14 days) every 3 weeks.

Results

In group 1, dose reduction was reported in 12 (57.1%) patients versus 1 patient in group 2 (5.3%; P = 0.0005). Patients in group 1 reported higher toxicity rates without any significant difference between the groups. The median duration of response was 17 weeks in group 1, while it was 19 weeks in group 2. Disease progression was recorded in 10 (47.6%) patients in group 1 versus 8 (42.1%) patients in group 2 (P = 0.81). The mean time to progression was 8.16 ± 0.63 months and the median was 10.1 months in group 1, while the mean was 8.98 ± 0.75 months and the median was 10 months in group 2 (P = 0.66). The overall survival had a mean of 11.94 ± 0.754 and 11.24 ± 0.665 months, while the median was 13.1 and 13 months in groups 1 and 2, respectively (P = 0.9).

Conclusion

A lower dose of capecitabine provides MBC patients with an active therapy that can be continued for prolonged periods to achieve long-term disease control without compromising its antitumor activity.

Population pharmacokinetic and pharmacodynamic modeling of capecitabine and its metabolites in breast cancer patients

PURPOSE

The present study was performed to examine relationships between systemic exposure of capecitabine metabolites (5-FU, 5'-DFCR and 5'-DFUR) and toxicity or clinical response in patients with metastatic breast cancer.

METHODS

A population pharmacokinetic model for capecitabine and its three metabolites was built. Typical parameter values, characteristics of random distributions, associated with parameters, and covariates impact were estimated. Area under the curve (AUC) were computed for 5-FU and compared with grades of toxicity. Pharmacokinetic modeling was based on data collected on the first treatment cycle. Toxicity was assessed on the two first treatment cycles.

RESULTS

The study was conducted in 43 patients. The population pharmacokinetic model (a one-compartment model per compound) was able to capture the very complex absorption process of capecitabine. Statistically significant covariates were cytidine deaminase, alkaline phosphatase and dihydrouracilemia (UH2)/uracilemia (U) ratio. UH2/U ratio was the most significant covariate on 5-FU elimination and CDA on the transformation of 5'-DFCR in 5'-DFUR. A trend was observed between 5-FU AUC and thrombopenia toxicity grades, but not with other toxicities. Best clinical response was not linked to systemic exposure of capecitabine metabolites.

CONCLUSION

In our study, we propose a model able to describe, meanwhile, and its main metabolites, with a complex absorption process and inclusion of enzyme activity covariates such as CDA and UH2/U ratio. Trial registration Eudract 2008-004136-20, 2008/11/26.

The relationship between eGFR and capecitabine efficacy/toxicity in metastatic breast cancer

The objective of this study was to evaluate the efficacy and toxicity of capecitabine in metastatic breast cancer (mBC) according to the estimated glomerular filtration rate (eGFR). A total of 135 patients included in the final analysis were stratified into 3 categories according to baseline eGFR, i.e., eGFR <60 mL/min/1.73 m² (Group 1), eGFR 60-90 mL/min/1.73 m² (Group 2) and eGFR >90 mL/min/1.73 m² (Group 3). If a patient developed a level of toxicity that would lead to capecitabine dose reduction, this was recognized as dose-limiting toxicity (DLT). The dose was reduced due to toxicity in 95 cycles. A total of 95 DLTs were seen in 76 (56.2%) of the 135 patients. When 76 patients with DLT were evaluated according to eGFR, DLT was observed in 93.3% of those in Group 1, 72.5% of those in Group 2 and 41.3% of those in Group 3 (p < 0.001). The median time to progression (TTP) of all patients was 7.4 months. No significant difference in TTP was observed in patients stratified into 3 groups according to eGFR. When the patients were divided into two groups as DLT and without DLT, the median TTP was 8.68 months (95% CI, 7.53-9.81 months) in those with toxicity and 6.23 months (95% CI, 4.04-8.43 months) in those without toxicity (log-rank p = 0.004). We found a significant relationship between low eGFR and increased risk of DLT. Having a DLT was associated with a longer TTP. It indicates the need for more data/larger study investigating these discrepancies.

Older cancer patients and COVID-19 outbreak: Practical considerations and recommendations

Since the COVID-19 outbreak started, it has been affecting mainly older individuals. Among the most vulnerable older individuals are those with cancer. Many published guidelines and consensus papers deal with prioritizing cancer care. Given the lack of high-quality evidence for management of cancer in older patients also in normal times, it is even more stringent to provide some resources on how to avoid both undertreatment and overtreatment in this population, who as of now is twice challenged to death, due to both a greater risk of getting infected with COVID-19 as well as from cancer not adequately addressed and treated. We hereby discuss some general recommendations (implement triage procedures; perform geriatric assessment; carefully assess comorbidity; promote early integration of palliative care in oncology; acknowledge the role of caregivers; maintain active take in charge to avoid feeling of abandonment; mandate seasonal flu vaccination) and discuss practical suggestions for specific disease settings (early-stage and advanced-stage disease for solid tumors, and hematological malignancies). The manuscript provides resources on how to avoid both undertreatment and overtreatment in older patients with cancer, who as of now is twice challenged to death, due to both a greater risk of getting infected with COVID-19 as well as from cancer not adequately addressed and treated.

SAHA Overcomes 5-FU Resistance in IFIT2-Depleted Oral Squamous Cell Carcinoma Cells

Simple Summary

IFIT2 depletion is associated with increased epithelial-mesenchymal transition and metastasis. The main aim of our study was to understand the link between drug resistance and IFIT2 depletion. In this study, we confirmed resistance to multiple common therapeutic drugs, particularly 5-FU, which showed especially high resistance in IFIT2-depleted cells. Interestingly, combination of SAHA and 5-FU overcame 5-FU resistance in IFIT2-depleted cells. Hence, our findings suggest that IFIT2 expression may be used as a biomarker to decide whether to undergo 5-FU treatment, but also the SAHA and 5-FU combination may be a potential new treatment regimen to augment 5-FU therapy in patients with thymidylate synthase-mediated drug-resistant oral squamous cell carcinoma.

Abstract

Interferon-induced protein with tetratricopeptide repeats 2 (IFIT2) is a member of the interferon-stimulated gene family that contains tetratricopeptide repeats (TPRs), which mediate protein–protein interactions in various biological systems. We previously showed the depletion of IFIT2 enhanced cell migration and metastatic activity in oral squamous cell carcinoma (OSCC) cells via the activation of atypical PKC signaling. In this study, we found that IFIT2-knockdown cells displayed higher resistance to 5-fluorouracil (5-FU) than control cells. The comet assay and annexin V analysis showed decreased DNA damage and cell death in IFIT2-knockdown cells compared to control cells treated with 5-FU. Cell cycle progression was also perturbed by 5-FU treatment, with the accumulation of IFIT2-depleted cells in S phase in a time-dependent manner. We further observed the overexpression of thymidylate synthase (TS) and thymidine kinase (TK) in IFIT2-knockdown cells. Inhibition of TS alone or double inhibition of TS and TK1 using the siRNA technique increased susceptibility to 5-FU in IFIT2-knockdown cells. We further identified that suberanilohydroxamic acid (SAHA) treatment decreased the expression of TS in IFIT2-knockdown cells and demonstrated that pretreatment with SAHA sensitized IFIT2-knockdown cells to 5-FU in vitro and in vivo. In conclusion, IFIT2 knockdown enhances TS expression, which mediates 5-FU resistance, and SAHA pretreatment suppresses TS expression and hence sensitizes cells to 5-FU. SAHA will be an effective strategy for the treatment of OSCC patients with 5-FU resistance.

Efficacy of different dosing schedules of capecitabine for metastatic breast cancer: a single-institution experience

Purpose Capecitabine is widely used as a single agent on a 21-day cycle in the management of metastatic breast cancer (MBC). Our primary objective was to compare the standard dosing of capecitabine (Arm A: days 1-14 on 21-day cycle) to biweekly dosing (Arm B: days 1-7 and 15-21 on 28-day cycle) using retrospective data analysis. Methods 166 patients with MBC treated with single agent capecitabine at The Ohio State University from 2002 to 2014 were considered eligible. Median time to treatment failure (TTF) and overall survival (OS) were estimated using Kaplan-Meier (KM) methods. KM curves were compared using log-rank tests with Holm's correction for multiplicity. Results Patients were grouped by dose schedule into one of three arms: Arm A (21-day cycle; capecitabine given at 1000 mg/m² orally, twice daily on days 1-14 of 21-day cycle); Arm B (28-day cycle; capecitabine given at 1000 mg/m² orally, twice daily on days 1-7 and 15-21 of 28-day cycle); and Arm C (changeover regimen where patients started on the 21-day cycle, but changed to a 28-day cycle for tolerability). No difference was found in TTF or OS for patients with MBC between those who received capecitabine on either standard dosing (Arm A) and those on a biweekly cycle (Arm B or C). Overall, 41% of patients required dose reduction. Conclusions Our single institution experience showed that alternate dosing of capecitabine (biweekly, 28-day cycle) may be a reasonable alternative to standard 21-day cycle with similar efficacy and fewer dose reductions.

Highly durable response to capecitabine in patient with metastatic estrogen receptor positive breast cancer: A case report

RATIONALE

In estrogen receptor-positive HER2-negative (ER+HER2-) metastatic breast cancer, chemotherapy should be offered only to patients who develop endocrine resistance or have a rapid disease progression. However, the correct sequence of chemotherapy administration is still debated.

PATIENT CONCERNS

We report the case of a 49-year-old woman with ER+ HER2- metastatic breast cancer who experienced an exceptionally long response to capecitabine administered as second-line therapy following a first-line anthracycline-based chemotherapy.

DIAGNOSES

The patient was diagnosed with ER+ HER2- metastatic breast cancer with massive liver involvement and mediastinal lymph nodes metastasis.

INTERVENTIONS

This patient was treated with capecitabine 1000 mg/mq bid given intermittently for 14 days within a 21-day cycle as a second-line therapy following a rapid progression on letrozole treatment given as a maintenance therapy.

OUTCOMES

Our patient experienced a progression-free survival (PFS) >3 years with an exceptionally good quality of life (QoL).

LESSONS

In ER+HER2- metastatic breast cancer patients, capecitabine monochemotherapy in second line may be associated with a particularly satisfactory PFS and no impact in terms of QoL. Future studies focused on biomarkers with predictive ability may help select patients who represent the best candidates to this treatment.

Relationship of fatigue with cognitive performance in women with early-stage breast cancer over 2 years

OBJECTIVE

Fatigue and cognitive dysfunction are major concerns for women with early-stage breast cancer during treatment and into survivorship. However, interrelationships of these phenomena and their temporal patterns over time are not well documented, thus limiting the strategies for symptom management interventions. In this study, changes in fatigue across treatment phases and the relationship among fatigue severity and its functional impact with objective cognitive performance were examined.

METHODS

Participants (N = 75) were assessed at five time points beginning prior to chemotherapy to 24 months after initial chemotherapy. Fatigue severity and impact were measured on the Brief Fatigue Inventory. Central nervous system (CNS) Vital Signs was used to measure performance based cognitive testing. Temporal changes in fatigue were examined, as well as the relationship between fatigue and cognitive performance, at each time point using linear mixed effect models.

RESULTS

Severity of fatigue varied as a function of phase of treatment. Fatigue severity and its functional impact were moderate at baseline, increased significantly during chemotherapy, and returned to near baseline levels by 2 years. At each time point, fatigue severity and impact were significantly associated with diminished processing speed and complex attention performance.

CONCLUSIONS

A strong association between fatigue and objective cognitive performance suggests that they are likely functionally related. That cognitive deficits were evident at baseline, whereas fatigue was more chemotherapy dependent, implicates that two symptoms share some common bases but may differ in underlying mechanisms and severity over time. This knowledge provides a basis for introducing strategies for tailored symptom management that vary over time.

The ABC7 regimen: a new approach to metastatic breast cancer using seven common drugs to inhibit epithelial-to-mesenchymal transition and augment capecitabine efficacy

Breast cancer metastatic to bone has a poor prognosis despite recent advances in our understanding of the biology of both bone and breast cancer. This article presents a new approach, the ABC7 regimen (Adjuvant for Breast Cancer treatment using seven repurposed drugs), to metastatic breast cancer. ABC7 aims to defeat aspects of epithelial-to-mesenchymal transition (EMT) that lead to dissemination of breast cancer to bone. As add-on to current standard treatment with capecitabine, ABC7 uses ancillary attributes of seven already-marketed noncancer treatment drugs to stop both the natural EMT process inherent to breast cancer and the added EMT occurring as a response to current treatment modalities. Chemotherapy, radiation, and surgery provoke EMT in cancer generally and in breast cancer specifically. ABC7 uses standard doses of capecitabine as used in treating breast cancer today. In addition, ABC7 uses 1) an older psychiatric drug, quetiapine, to block RANK signaling; 2) pirfenidone, an anti-fibrosis drug to block TGF-beta signaling; 3) rifabutin, an antibiotic to block beta-catenin signaling; 4) metformin, a first-line antidiabetic drug to stimulate AMPK and inhibit mammalian target of rapamycin, (mTOR); 5) propranolol, a beta-blocker to block beta-adrenergic signaling; 6) agomelatine, a melatonergic antidepressant to stimulate M1 and M2 melatonergic receptors; and 7) ribavirin, an antiviral drug to prevent eIF4E phosphorylation. All these block the signaling pathways - RANK, TGF-beta, mTOR, beta-adrenergic receptors, and phosphorylated eIF4E - that have been shown to trigger EMT and enhance breast cancer growth and so are worthwhile targets to inhibit. Agonism at MT1 and MT2 melatonergic receptors has been shown to inhibit both breast cancer EMT and growth. This ensemble was designed to be safe and augment capecitabine efficacy. Given the expected outcome of metastatic breast cancer as it stands today, ABC7 warrants a cautious trial.

The efficacy and toxicity profile of metronomic chemotherapy for metastatic breast cancer: A meta-analysis

Purpose

The current meta-analysis aimed to summarize the available evidence for the efficacy and serious adverse events (AEs) associated with use of metronomic chemotherapy (MCT) in patients with metastatic breast cancer (MBC).

Method

Electronic databases (PubMed, EMBASE database, Web of Knowledge, and the Cochrane database) were systematically searched for articles related to the use of MCT in MBC patients. Eligible studies included clinical trials of MBC patients treated with MCT that presented sufficient data related to tumor response, progression-free survival (PFS), overall survival (OS), and grade 3/4 AEs. A meta-analysis was performed using a random effects model.

Results

This meta-analysis consists of 22 clinical trials with 1360 patients. The pooled objective response rate and clinical benefit rate of MCT were 34.1% (95% CI 27.4–41.5) and 55.6% (95% CI 49.2–61.9), respectively. The overall 6-month PFS, 12-month OS, and 24-month OS rates were 56.8% (95% CI 48.3–64.9), 70.3% (95% CI 62.6–76.9), and 40.0% (95% CI 30.6–50.2), respectively. The pooled incidence of grade 3/4 AEs was 29.5% (95% CI 21.1–39.5). There was no statistically significant difference observed in any endpoint between subgroups defined by concomitant anti-cancer therapies or chemotherapy regimens. After excluding one controversial study, we observed a trend showing lower toxicity rates with the use of MCT alone compared to use of MCT with other anti-cancer therapies (P = 0.070).

Conclusions

Metronomic chemotherapy may be effective for use in patients with metastatic breast cancer. MCT used alone is possibly equally effective and less toxic than combination therapies. Well-designed RCTs are needed to obtain more evidence.