Randomised phase II trial of gemcitabine plus vinorelbine vs gemcitabine plus cisplatin vs gemcitabine plus capecitabine in patients with pretreated metastatic breast cancer

Intratumoral bacteria are an important "accomplice" in tumor development and metastasis

As emerging tumor components, intratumoral bacteria have been found in many solid tumors. Several studies have demonstrated that different cancer subtypes have distinct microbial compositions, and mechanistic studies have shown that intratumoral bacteria may promote cancer initiation and progression through DNA damage, epigenetic modification, inflammatory responses, modulation of host immunity and activation of oncogenes or oncogenic pathways. Moreover, intratumoral bacteria have been shown to modulate tumor metastasis and chemotherapy response. A better understanding of the tumor microenvironment and its associated microbiota will facilitate the design of new metabolically engineered species, opening up a new era of intratumoral bacteria-based cancer therapy. However, many questions remain to be resolved, such as where intratumoral bacteria originate and whether there is a direct causal relationship between intratumoral bacteria and tumor susceptibility. In addition, suitable preclinical models and more advanced detection techniques are crucial for studying the biological functions of intratumoral bacteria. In this review, we summarize the complicated role of intratumoral bacteria in the regulation of cancer development and metastasis and discuss their carcinogenic mechanisms and potential therapeutic aspects.

Development of cisplatin resistance in breast cancer MCF7 cells by up-regulating aldo-keto reductase 1C3 expression, glutathione synthesis, and proteasomal proteolysis

Cisplatin (CDDP) is widely prescribed for the treatment of various cancers including bladder cancers, whereas its clinical use for breast cancer chemotherapy is restricted owing to easy acquisition of the chemoresistance. Here, we established a highly CDDP-resistant variant of human breast cancer MCF7 cells and found that procuring the resistance aberrantly elevates the expression of aldo-keto reductase (AKR) 1C3. Additionally, MCF7 cell sensitivity to CDDP was decreased and increased by overexpression and knockdown, respectively, of AKR1C3, clearly inferring that the enzyme plays a crucial role in acquiring the CDDP resistance. The CDDP-resistant cells suppressed the formation of cytotoxic reactive aldehydes by CDDP treatment, and the suppressive effects were almost completely abolished by pretreating with AKR1C3 inhibitor. The resistant cells also exhibited the elevated glutathione amount and 26S proteasomal proteolytic activities, and their CDDP sensitivity was significantly augmented by pretreatment with an inhibitor of glutathione synthesis or proteasomal proteolysis. Moreover, the combined treatment with inhibitors of AKR1C3, glutathione synthesis, and/or proteasomal proteolysis potently overcame the CDDP resistance and docetaxel cross-resistance. Taken together, our results suggest that the combination of inhibitors of AKR1C3, glutathione synthesis, and/or proteasomal proteolysis is effective as an adjuvant therapy to enhance CDDP sensitivity of breast cancer cells.

Hepatic Artery Infusion Pump Combined With Systemic Chemotherapy for Patients With Liver Metastases From Breast Carcinoma

Background: When liver metastasis in patients with breast cancer is diagnosed, treatment is generally palliative and usually consists of systemic therapies only. This study aimed to evaluate the efficacy and safety of hepatic arterial infusion (HAI) combined with systemic chemotherapy in patients with breast carcinoma liver metastases (BCLM). Methods: From January 2012 to December 2019, HAI catheter systems were implanted under the guide of digital subtract angiography (DSA) in 19 patients with BCLM. All patients received systemic chemotherapy and HAI gemcitabine plus floxuridine (FUDR). Methods: The overall response rate (ORR) of intrahepatic lesions was 73.7%, including 2 patients (10.5%) with complete remission (CR) and 12 patients (63.2%) with partial remission (PR). Additionally, we found that young patients (age < 55 years) had a higher ORR than the older (100% vs 44.4%, P = .011). The median overall survival (mOS) was 13.1 months. Kaplan-Meier survival curves demonstrated that the mOS was not significantly different between patients with < 9 intrahepatic lesions and those with ≥ 9 lesions (13.7 months vs 10.9 months, P = .225). The mOS was 14.3 and 10.6 months for patients without extrahepatic metastases and with extrahepatic metastases, respectively (P = .016). None of the patients had grade 4 toxicity. The grade 3 toxicities included leucopenia, neutropenia and diarrhea. Conclusions: HAI gemcitabine plus FUDR combined with systemic chemotherapy is effective in achieving a high local response and prolonging mOS for patients with BCLM and is associated with a relatively low rate of toxicity.

Capecitabine for hormone receptor-positive versus hormone receptor-negative breast cancer

BACKGROUND

Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer.

OBJECTIVES

To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic.

SEARCH METHODS

On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model.

MAIN RESULTS

We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes).

AUTHORS' CONCLUSIONS

In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.

The Impact of Platinum-Containing Chemotherapies in Advanced Triple-Negative Breast Cancer: Meta-Analytical Approach to Evaluating Its Efficacy and Safety

BACKGROUND

Triple-negative breast cancer (TNBC), the most common type of breast cancer, is associated with poor patient prognosis. Platinum-containing chemotherapies are commonly used in the treatment and prevention of advanced TNBC.

OBJECTIVES AND METHODS

To systematically evaluate the effectiveness and safety of platinum-containing chemotherapies in patients with advanced TNBC, we searched several databases, including PubMed, Medline, Embase, ClinicalTrials.gov, Cochrane Library, CNKI, CBM, and the Chinese Cochrane Center, to collect published randomized controlled clinical studies of platinum-containing chemotherapies for advanced TNBC before November 2020. The meta-analysis was performed using Review Manager version 5.3. To assess effectiveness and safety, dichotomous and continuous variables were assessed using odds ratio (OR) and mean difference (MD), respectively, with 95% CI.

RESULTS

A total of 1,222 patients with advanced TNBC were enrolled in 11 eligible trials, including 489 patients in the treatment group (platinum-containing) and 447 patients in the control group (non-platinum-containing). We also retrieved information whether a PARP inhibitor was combined with platinum-containing chemotherapy for patients with metastatic TNBC and identified 224 patients who received a PARP inhibitor combined with platinum-containing chemotherapy and 62 patients in the platinum-containing group who did not. The platinum-containing chemotherapy group had a significantly better objective response rate (OR 1.43, 95% CI 1.20-1.71, p < 0.001) and longer progression-free survival (PFS; MD 1.15, 95% CI 0.03-2.28, p < 0.05) than the non-platinum-containing chemotherapy group. However, there was no significant difference in overall survival (OS) of patients with advanced TNBC between the two groups (MD 2.04, 95% CI -0.83 to 4.91, p > 0.05). Related adverse effects of platinum-containing chemotherapies involved gastrointestinal reaction, myelosuppression and liver function damage. Platinum-containing chemotherapies were not associated with an increased incidence of adverse side effects compared with non-platinum-containing chemotherapies, with the exception of nausea and vomiting (OR 2.22, 95% CI 1.10-4.46, p < 0.05). Furthermore, the addition of the PARP inhibitor iniparib to gemcitabine and carboplatin treatment improved the rate of clinical benefit, OS and PFS.

CONCLUSIONS

Platinum-containing chemotherapy remains a highly recommended therapeutic regimen due to greater effectiveness and tolerance for patients with advanced TNBC.

Maintenance chemotherapy after 6 cycles of platinum-doublet regimen in anthracycline-and taxane-pretreated metastatic breast cancer

BACKGROUND/AIMS

Sequential monotherapy is recommended for anthracycline-and taxane-resistant metastatic breast cancer (MBC), but combination chemotherapy is considered in patients with visceral crisis. Cisplatin-doublet chemotherapy is a combination regimen for MBC, but prolonged treatment is challenging because of toxicity. We analyzed the role of single-agent maintenance chemotherapy after cisplatin-doublet chemotherapy for MBC.

METHODS

From January 2011 to December 2017, 96 anthracycline- and taxane- resistant MBC patients were retrospectively reviewed, and 49 patients with a sustained clinical benefit during the initial 6 cycles of cisplatin-doublet chemotherapy were enrolled for study. Patients were treated with gemcitabine-cisplatin (gemcitabine, 1,250 mg/m2, intravenously [IV], days 1 to 8; cisplatin 60 mg/m2, IV, day 1) or capecitabine-cisplatin (capecitabine 2,500 mg/m2, orally, days 1 to 14; cisplatin 60 mg/m2, IV, day 1) during the induction period. After 6 cycles, 16 patients were switched to single-maintenance treatment (gemcitabine or capecitabine) and the doublet regimen was continued in 24 patients. Survival outcomes (progression- free survival [PFS] and overall survival [OS]) were analyzed.

RESULTS

Among the 49 patients who showed a clinical benefit during cisplatin- doublet therapy, 24 were maintained on the doublet regimen, 16 were switched to single-maintenance treatment, and chemotherapy was suspended until disease progression in nine patients. The single-maintenance chemotherapy group showed superior survival than the chemotherapy holiday and doublet regimen groups (median PFS 15.43 months vs. 8.37 and 10.67 months, respectively, p = 0.008; median OS 43.67 months vs. 22.17 and 22.33 months, respectively, p = 0.014).

CONCLUSION

Patients showing a clinical benefit during 6 cisplatin-doublet chemotherapy cycles may have a sustained survival benefit from single-maintenance chemotherapy.

Platinum-containing regimens for triple-negative metastatic breast cancer

BACKGROUND

In a previous Cochrane Review, we found that for women with metastatic breast cancer unselected for triple-negative disease, there is little or no survival benefit and excess toxicity from platinum-based regimens. In subgroup analyses, however, we found preliminary low-quality evidence of a survival benefit from platinum-based regimens for women with metastatic triple-negative breast cancer (mTNBC). This review updates the evidence from the mTNBC subgroup analyses in the previous Cochrane Review.

OBJECTIVES

To assess the effects of platinum-containing chemotherapy regimens with regimens not containing platinum in the management of women with mTNBC.

SEARCH METHODS

We obtained relevant studies published prior to 2015 and their extracted results from the mTNBC subgroup analysis in the previous Cochrane Review. We searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.gov between 2015 and 27 September 2019. We identified further potentially relevant studies from previous trial reports, systematic reviews, and meta-analyses.

SELECTION CRITERIA

Randomised trials comparing platinum-containing chemotherapy regimens with regimens not containing platinum in women with mTNBC. Individual trials could compare one or more platinum-based regimens to one or more non-platinum regimens; hence there could be more 'treatment-comparisons' (i.e. platinum regimen versus non-platinum regimen comparison) than trials. Trial participants may have been purposely selected for mTNBC or inadvertently selected as a subgroup.

DATA COLLECTION AND ANALYSIS

At least two independent reviewers assessed studies for eligibility and quality, and extracted all relevant data from each study. We derived hazard ratios (HRs) for time-to-event outcomes, where possible, and used fixed-effect models for meta-analyses. We analysed objective tumour response rates (OTRRs) and toxicities as binary (dichotomous) outcomes with risk ratios (RRs) used as measures of effects. We extracted quality of life data, if available. We used GRADE to rate the quality of evidence for time-to-event and tumour response outcomes.

MAIN RESULTS

This review includes 13 treatment-comparisons involving 1349 women from 10 studies. Twelve of the 13 treatment-comparisons were included in one or more meta-analyses. Of the 13 treatment-comparisons, six and eight had published or provided time-to-event data on overall survival (OS) or progression-free survival/time to progression (PFS/TTP), respectively, that could be included in meta-analyses. Ten treatment-comparisons published or provided OTRR data that could be included in meta-analyses. Eight of the 13 treatment-comparisons were from studies that selected participants on the basis of mTNBC status, while the other five treatment-comparisons were from studies that reported mTNBC results as part of subgroup analyses. Analysis of six treatment-comparisons indicated that platinum-containing regimens may have provided a small survival benefit to mTNBC patients (HR 0.85, 95% CI 0.73 to 1.00; 958 women; moderate-quality evidence) with no evidence of heterogeneity (P = 0.41; I2 = 1%). Data from eight treatment-comparisons showed that platinum regimens may improve PFS/TTP (HR 0.77, 95% CI 0.68 to 0.88; 1077 women; very low-quality evidence). There was marked evidence of heterogeneity (P < 0.0001; I2 = 80%). There was also low-quality evidence of better tumour response for platinum recipients (RR 1.40, 95% CI 1.22 to 1.59; 1205 women) with some evidence of heterogeneity (P = 0.01; I2 = 58%). The observed heterogeneity for the PFS/TTP and OTRR outcomes may reflect between-study differences and general difficulties in assessing tumour response, as well as the varying potencies of the comparators. Compared with women receiving non-platinum regimens: rates of grade 3 and 4 nausea/vomiting were higher for platinum recipients (RR 4.77, 95% CI 1.93 to 11.81; 655 women; low-quality evidence) and rates of grade 3 and 4 anaemia were higher for platinum recipients (RR 3.80, 95% CI 2.25 to 6.42; 843 women; low-quality evidence). In general, however, relatively few intervention-comparisons could be included in meta-analyses for adverse events. None of the studies reported quality of life.

AUTHORS' CONCLUSIONS

For women with mTNBC, there was moderate-quality evidence of a small survival benefit from platinum-based regimens compared to non-platinum regimens. This finding is consistent with findings of a PFS/TTP benefit and improved tumour response from platinum-based regimens. These potential benefits, however, should be weighed against previously identified excess toxicities from platinum-based regimens, particularly regimens containing cisplatin. Further randomised trials of platinum-based regimens among women with mTNBC are required.

Drug repurposing for breast cancer therapy: Old weapon for new battle

Despite tremendous resources being invested in prevention and treatment, breast cancer remains a leading cause of cancer deaths in women globally. The available treatment modalities are very costly and produces severe side effects. Drug repurposing that relate to new uses for old drugs has emerged as a novel approach for drug development. Repositioning of old, clinically approved, off patent non-cancer drugs with known targets, into newer indication is like using old weapons for new battle. The advances in genomics, proteomics and information computational biology has facilitated the process of drug repurposing. Repositioning approach not only fastens the process of drug development but also offers more effective, cheaper, safer drugs with lesser/known side effects. During the last decade, drugs such as alkylating agents, anthracyclins, antimetabolite, CDK4/6 inhibitor, aromatase inhibitor, mTOR inhibitor and mitotic inhibitors has been repositioned for breast cancer treatment. The repositioned drugs have been successfully used for the treatment of most aggressive triple negative breast cancer. The literature review suggest that serendipity plays a major role in the drug development. This article describes the comprehensive overview of the current scenario of drug repurposing for the breast cancer treatment. The strategies as well as several examples of repurposed drugs are provided. The challenges associated with drug repurposing are discussed.

Metastatic and triple-negative breast cancer: challenges and treatment options

The major current conventional types of metastatic breast cancer (MBC) treatments include surgery, radiation, hormonal therapy, chemotherapy, or immunotherapy. Introducing biological drugs, targeted treatment and gene therapy can potentially reduce the mortality and improve the quality of life in patients with MBC. However, combination of several types of treatment is usually recommended. Triple negative breast cancer (TNBC) accounts for 10-20% of all cases of breast carcinoma and is characterized by the low expression of progesterone receptor (PR), estrogen receptor (ER), and human epidermal growth factor receptor 2 (HER2). Consequently, convenient treatments used for MBC that target these receptors are not effective for TNBC which therefore requires special treatment approaches. This review discusses the occurrence of MBC, the prognosis and predictive biomarkers of MBC, and focuses on the novel advanced tactics for treatment of MBC and TNBC. Nanotechnology-based combinatorial approach for the suppression of EGFR by siRNA and gifitinib is described.

Targeting FOSB with a cationic antimicrobial peptide, TP4, for treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) currently lacks a suitable therapeutic candidate and is thus difficult to treat. Here, we report that a cationic antimicrobial peptide (CAP), tilapia piscidin 4 (TP4), which was derived from Nile tilapia (Oreochromis niloticus), is selectively toxic to TNBC. TP4 acts by inducing an AP-1 protein called FOSB, the expression of which is negatively associated with the pathological grade of TNBC. We show that TP4 is bound to the mitochondria where it disrupts calcium homeostasis and activates FOSB. FOSB overexpression results in TNBC cell death, whereas inhibition of calcium signaling eliminates FOSB induction and blocks TP4-induced TNBC cell death. Both TP4 and anthracyclines strongly induced FOSB, particularly in TNBC, indicating that FOSB may be suitable as a biomarker of drug responses. This study thus provides a novel therapeutic approach toward TNBC through FOSB induction.

Efficacy and Safety of Vinorelbine Plus Cisplatin vs. Gemcitabine Plus Cisplatin for Treatment of Metastatic Triple-Negative Breast Cancer After Failure with Anthracyclines and Taxanes

BACKGROUND This study aimed to compare the efficacy and safety of vinorelbine plus cisplatin (NP regimen) vs. gemcitabine plus cisplatin (GP regimen) for treatment of metastatic TNBC after failure with anthracyclines and taxanes. MATERIAL AND METHODS A total of 48 patients with metastatic TNBC that failed in anthracyclines and taxanes treatment were enrolled and randomly grouped. Patients in the NP group (n=22) were given 25 mg/m² vinorelbine on days 1 and 8 and 25 mg/m² cisplatin on days 2-4 of each 21-day cycle, while subjects in the GP group (n=26) were administered 1000 mg/m² gemcitabine on days 1 and 8 and 25 mg/m² cisplatin on days 2-4 of each 21-day cycle. The treatment response and adverse events were compared between the 2 groups every 2 cycles. RESULTS The ORR, DCR, and median TTP were 45.5%, 77.3%, and 5 months in the NP group, and 46.2%, 80.8%, and 5.2 months in the GP group, and no significant differences were observed in ORR, DCR, and median TTP between the 2 groups (P>0.05). The major adverse events included grade I-II bone marrow inhibition, gastrointestinal reactions, and phlebitis, and a lower incidence of thrombocytopenia and rash and a higher incidence of phlebitis was found in the NP group than in the GP group (P<0.05). CONCLUSIONS Either NP or GP regimen is active and tolerated in treatment of metastatic TNBC with anthracyclines and/or taxanes resistance, which may be used as a salvage treatment for metastatic TNBC.

Platinum-containing regimens for metastatic breast cancer

BACKGROUND

Studies have reported high tumour response rates for platinum-containing regimens in the treatment of women with metastatic breast cancer. Most of these studies were conducted prior to the 'intrinsic subtype' era, and did not specifically focus on metastatic triple-negative breast cancers (mTNBCs).

OBJECTIVES

To identify and review the evidence from randomised trials comparing platinum-containing chemotherapy regimens with regimens not containing platinum in the management of women with metastatic breast cancer.

SEARCH METHODS

For this review update, we searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.gov on 28 May 2015. We identified further potentially relevant studies from handsearching references of previous trials, systematic reviews, and meta-analyses. Prior to this review update, the most recent search for studies was conducted in May 2003 for the original 2004 review.

SELECTION CRITERIA

Randomised trials comparing platinum-containing chemotherapy regimens with regimens not containing platinum in women with metastatic breast cancer.

DATA COLLECTION AND ANALYSIS

At least two independent reviewers assessed studies for eligibility and quality, and extracted all relevant data from each study. Hazard ratios (HRs) were derived for time-to-event outcomes, where possible, and fixed-effect models were used for meta-analyses. Objective tumour response rates (OTRRs) and toxicities were analysed as binary (dichotomous) outcomes with risk ratios (RRs) used as measures of effects. Quality of life data were extracted where available. GRADE was used to rate the quality of evidence for survival and tumour response outcomes at the level of subgroups selected and unselected for mTNBC, and for toxicity outcomes based on combining data from selected and unselected populations.

MAIN RESULTS

This update includes 15 new eligible treatment-comparisons from 12 studies. In total, 28 treatment-comparisons, involving 4418 women, from 24 studies are now included in one or more meta-analyses. Of the 28 treatment-comparisons, 19 and 16 had published or provided extractable time-to-event data on overall survival (OS) or progression-free survival/time to progression (PFS/TTP), respectively. All 28 treatment-comparisons provided OTRR data that could be included in meta-analyses. Most women recruited to the studies were not selected on the basis of mTNBC status.In a subgroup of three treatment-comparisons assessing women with mTNBC, platinum-containing regimens may have provided a survival benefit (HR 0.75, 95% CI 0.57 to 1.00; low-quality evidence). In women unselected for intrinsic subtypes such as mTNBC, there was little or no effect on survival (HR 1.01, 95% CI 0.92 to 1.12; high-quality evidence). This effect was similar to the combined analysis of survival data for both populations (HR 0.98, 95% CI 0.89 to 1.07; I2 =39%, 1868 deaths, 2922 women; 19 trials). The difference in treatment effects between mTNBC women compared with unselected women was of borderline statistical significance (P = 0.05).Data from three treatment-comparisons with mTNBC participants showed that platinum regimens may improve PFS/TTP (HR 0.59, 95% CI 0.49 to 0.72; low-quality evidence). Thirteen treatment-comparisons of unselected metastatic participants showed that there was probably a small PFS/TTP benefit for platinum recipients, although the confidence interval included no difference (HR 0.92, 95% CI 0.84 to 1.01; moderate-quality evidence). Combined analysis of data from an estimated 1772 women who progressed or died out of 2136 women selected or unselected for mTNBC indicated that platinum-containing regimens improved PFS/TTP (HR 0.85, 95% CI 0.78 to 0.93). There was marked evidence of heterogeneity (P = 0.0004; I2 = 63%). The larger treatment benefit in mTNBC women compared with unselected women was statistically significant (P < 0.0001).There was low-quality evidence of better tumour response in both subgroups of women with mTNBC and unselected women (RR 1.33, 95% CI 1.13 to 1.56; RR 1.11, 95% CI 1.04 to 1.19, respectively). Combined analysis of both populations was closer to the effect in unselected women (RR 1.15, 95% CI 1.08 to 1.22; 4130 women). There was considerable evidence of heterogeneity (P < 0.0001; I2 = 64%), which may reflect between-study differences and general difficulties in assessing response, as well as the varying potencies of the comparators.Compared with women receiving non-platinum regimens: rates of grade 3 and 4 nausea/vomiting were probably higher among women receiving cisplatin- (RR 2.65, 95% CI 2.10 to 3.34; 1731 women; moderate-quality evidence) but the effect from carboplatin-containing regimens was less certain (RR 0.77, 95% CI 0.47 to 1.26; 1441 women; moderate-quality evidence); rates of grade 3 and 4 anaemia were higher among women receiving cisplatin- (RR 3.72, 95% CI 2.36 to 5.88; 1644 women; high-quality evidence) and carboplatin-containing regimens (RR 1.72, 95% CI 1.10 to 2.70; 1441 women; high-quality evidence); rates of grade 3 and 4 hair loss (RR 1.41, 95% CI 1.26 to 1.58; 1452 women; high-quality evidence) and leukopenia (RR 1.38, 95% CI 1.21 to 1.57; 3176 women; moderate-quality evidence) were higher among women receiving platinum-containing regimens (regardless of platinum agent).

AUTHORS' CONCLUSIONS

In women with metastatic breast cancer who do not have triple-negative disease, there is high-quality evidence of little or no survival benefit and excess toxicity from platinum-based regimens. There is preliminary low-quality evidence of a moderate survival benefit from platinum-based regimens for women with mTNBC. Further randomised trials of platinum-based regimens in this subpopulation of women with metastatic breast cancer are required.

Gemcitabine and Vinorelbine Combination Chemotherapy in Taxane-Pretreated Patients with Metastatic Breast Cancer: A Phase II Study of the Kinki Multidisciplinary Breast Oncology Group (KMBOG) 1015

Background: This phase II study was conducted to evaluate the efficacy and safety of the chemotherapy combination of gemcitabine and vinorelbine in taxane-pretreated Japanese metastatic breast cancer patients. Methods: In this multicenter, phase II, single-arm study, patients with recurrent or metastatic HER2-negative breast cancer were administered gemcitabine (1,200 mg/m2) and vinorelbine (25 mg/m2) intravenously on days 1 and 8 every 3 weeks. The primary endpoint was the objective response rate, and other endpoints included progression-free survival, overall survival, and safety. Results: A total of 42 patients were enrolled in this study. The objective response rate and clinical benefit rate were 24 and 43%, respectively. The median progression-free survival was 4.0 months. The median overall survival was 11.1 months. Grade 3/4 neutropenia was the most common hematologic toxicity, occurring in 22 patients (54%). Nonhematologic toxicity was moderate and transient, with fatigue (48%) being the most common condition and no severe adverse event reported. Conclusion: The combination of gemcitabine and vinorelbine is an effective and tolerable regimen for HER2-negative, taxane-pretreated, metastatic breast cancer patients in Japan.

Platinum salts in advanced breast cancer: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The interest in platinum salts in breast cancer (BC) therapy has been recently renewed as inhibition of DNA damage response may enhance the effects of DNA-damaging agents in BC tumors with high genomic instability. The present systematic review and meta-analysis of randomized trials were performed to assess the efficacy and safety of therapy with platinum salts in patients with locally advanced or metastatic (hereinafter advanced) BC.

METHODS

We searched PubMed, EMBASE, SCOPUS, Web of Science, the Cochrane Library, and CINAHL for phase II/III clinical trials that assessed efficacy of platinum-based therapy in patients with advanced BC. Pooled estimates of overall response rate (RR), median progression-free survival (PFS) and overall survival (OS) were computed using random or fixed effects models.

RESULTS

Data on 4625 patients from 23 phase II and III trials (11 with cisplatin, 11 with carboplatin, and 1 with either agents respectively) were analyzed. Estimates for RR, PFS, and OS were obtained from 23, 13, and 15 studies, respectively. Although at the cost of significantly increased fatigue, hematological and gastrointestinal toxicity, compared with non-platinum schemas, cisplatin, and carboplatin prolonged OS (HR 0.91; 95 % CI 0.83-1.00, p = 0.04), PFS (HR 0.84; 95 % CI 0.73-0.97, p = 0.01), and RR (HR 1.27; 95 % CI 1.03-1.57, p = 0.03).

CONCLUSIONS

Despite some limitations of the studies examined, including partial information on hormonal receptor and HER2 status, the use of platinum salts significantly prolonged OS, and PFS of patients with advanced BC with no unexpected toxicity.

Gemcitabine and Capecitabine Combination Chemotherapy in Patients with Metastatic Breast Cancer Pretreated with Anthracyclines and/or Taxanes

BACKGROUND

Owing to the need for effective and tolerable new regimens for the treatment of patients with metastatic breast cancer (MBC) previously treated with anthracyclines and/or taxanes, we aimed to assess the activity and safety of the gemcitabine plus capecitabine combination chemotherapy.

METHODS

Sixty-four patients were enrolled. Treatment consisted of gemcitabine 1,000 mg/m2 intravenously on days 1 and 8, plus oral capecitabine at 1,250 mg/m2 twice daily on days 1-14. The primary end point was the overall response rate (ORR). Secondary objectives included the disease control rate (DCR), overall survival (OS), progression-free survival (PFS), toxicity, and predictive factors.

RESULTS

In the 64 patients, the ORR and DCR was 28.1 and 67.2%. Median OS and PFS were 23.6 and 13.4 months, respectively. Toxicities were mild and curable.

CONCLUSION

The combination of gemcitabine and capecitabine is an effective and tolerable treatment for MBC previously treated with anthracyclines and/or taxanes.

The prognostic values of CYP2B6 genetic polymorphisms and metastatic sites for advanced breast cancer patients treated with docetaxel and thiotepa

This study investigated interactive effects of CYP2B6 genotypes and liver metastasis on the prognosis of metastatic breast cancer patients who received combined chemotherapy of docetaxel and thiotepa. Totally 153 patients were retrospectively genotyped rs8192719 (c.1294 + 53C > T) and rs2279343 (c.785A > G). Kaplan-Meier method and Cox Proportional Hazard Regression model were used to estimate the survival. Patients with liver metastasis had worsen prognosis, conferring a 2.26-fold high risk of progression and 1.93-fold high risk of death (p < 0.05). Both CT/TT genotype of rs8192719 (c.1294 +  3C > T) and AG genotype of rs2279343 (c.785A > G) prolonged survival (p < 0.05). Furthermore, among liver metastatic patients, AG genotype of rs2279343 (c.785A > G) was associated with a 47% reduced risk of death and a 6-month-longer overall survival (p < 0.05). Among non-liver metastatic patients, hazard ratios of CT/TT genotype of rs8192719 (c.1294 + 53C > T) were 0.45 for progression and 0.40 for death; and the corresponding survival was improved by 6 months and 16 months, respectively (p < 0.05). Genotypes of CYP2B6 had an interaction with clinical efficacy of docetaxel and thiotepa on metastatic breast cancer patients; and metastatic sites also affected clinical responses. Further therapies should take into account of chemotherapy regimen, genotypes of metabolizing enzymes and metastatic sites for the particular subpopulation.

Gemcitabine and Vinorelbine (GemVin) Regimen

The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases. Questions or suggestions for topics should be addressed to Dominic A. Solimando, Jr, President, Oncology Pharmacy Services, Inc., 4201 Wilson Blvd #110-545, Arlington, VA 22203, e-mail: OncRxSvc@comcast.net; or J. Aubrey Waddell, Professor, University of Tennessee College of Pharmacy; Oncology Pharmacist, Pharmacy Department, Blount Memorial Hospital, 907 E. Lamar Alexander Parkway, Maryville, TN 37804, e-mail: waddfour@charter.net.

Phase I and II Study of Gemcitabine and Vinorelbine in Heavily Pretreated Patients with Metastatic Breast Cancer and Review of the Literature

Background: Many phase II trials investigated the combination of Gemcitabine (G) and Vinorelbine (V) in the treatment of metastatic breast cancer (MBC) with variable outcomes. This study was conducted to explore whether this combination was effective and tolerable in MBC patients who were heavily pretreated with anthracyclines and taxanes. Methods: A phase I study was conducted first to establish the maximum tolerated dose (MTD) of the G and V combination in MBC patients. Then, a phase II study evaluated the response rates, the median time to progression (TTP), the overall survival (OS) as well as the toxicities resulting from this combination at the MTD. Results: Nine patients were enrolled in the phase I study. The MTD was identified as 700mg/m² of G on days 1 and 8 in combination with 15 mg/m² of V on days 2 and 9, every 21 days. Twenty-one of 25 patients involved in the phase II study were evaluable for response. No complete or partial responses were achieved; 6 patients (24.0%) had stable disease and 15 (60.0%) progressed. The median TTP was 2 months and the median OS 10 months. Grade 3/4 Neutropenia was the major hematologic toxicity, occurring in 52% of the cycles. The most common non-hematologic grade 3/4 toxicities were fatigue (18%), myalgias (17%) and arthralgias (13%). Conclusion: In heavily pretreated patients with MBC, the combination of G and V at the doses stated above was ineffective as it did not induce partial or complete responses. Other chemotherapy agents or combinations should be evaluated in future studies.

Optimal strategies for the treatment of metastatic triple-negative breast cancer with currently approved agents

Triple-negative breast cancer (TNBC) is an aggressive histological subtype with limited treatment options and very poor prognosis following progression after standard chemotherapeutic regimens. Resistance to current standard therapies such as anthracyclines or taxanes limits the available options for previously treated patients with metastatic TNBC to a small number of non-cross-resistant regimens, and there is currently no preferred standard chemotherapy. Duration of response is usually short, with rapid relapse very common and median survival of just 13 months. The newly approved agent eribulin has shown a survival benefit in patients who had previously been treated with anthracycline- or taxane-containing regimens, including in patients with TNBC. Platinum-based regimens are an emerging option for patients with BRCA1 mutation, and newer targeted agents such as anti-angiogenic treatment with bevacizumab or anti-epidermal growth factor receptor treatment with cetuximab, have shown some benefit in combination therapy. However, there remains an urgent unmet need for improved targeted agents for this patient population. Improved treatment may be facilitated by biomarker-led understanding of subgroup molecular targets, which may predict benefit from currently approved agents, as well as newer targeted drugs.

Efficacy and toxicity of capecitabine-based chemotherapy in patients with metastatic or advanced breast cancer: results from ten randomized trials

OBJECTIVE

The efficacy and adverse effects of capecitabine-based chemotherapy versus other regimens reported in previous trials were discordant. The aim of the present study was to determine the efficacy and toxicity profiles of capecitabine-based chemotherapy versus capecitabine-free regimens in patients with metastatic and/or advanced breast cancer.

METHODS

Randomized trials in which capecitabine-based chemotherapy was compared with capecitabine-free chemotherapy were included by searching the PubMed database. Differences in efficacy and grade 3-4 toxicities between capecitabine-based chemotherapy and other chemotherapy were compared.

RESULTS

Ten randomized controlled trials were included in our meta-analysis. Compared to patients treated with capecitabine-free chemotherapy, patients treated with capecitabine-based chemotherapy did not have a significantly different complete response (odds ratio (OR): 1.25, 95% confidence interval (CI): 0.87-1.79, p = 0.231), partial response (OR: 1.16, 95% CI: 0.95-1.41, p = 0.147), and overall response (OR: 1.21, 95% CI: 1.00-1.47, p = 0.053). Compared to the capecitabine-free group, less hematological toxicity and more gastrointestinal toxicity occurred in patients treated with capecitabine-based chemotherapy, including neutropenia (OR: 0.34, 95% CI: 0.19-0.59, p <0.001), anemia (OR: 0.41, 95% CI: 0.20-0.85, p = 0.016), leukocytopenia (OR: 0.50, 95% CI: 0.32-0.78, p = 0.002), and diarrhea (OR: 2.35, 95% CI: 1.62-3.42, p < 0.001). Furthermore, patients in the capecitabine group exhibited a significantly higher rate of grade 3 hand-foot syndrome than the capecitabine-free group (OR: 25.16, 95% CI: 12.27-51.58, p < 0.001).

CONCLUSIONS

The present study suggests that capecitabine-based chemotherapy is as effective as capecitabine-free chemotherapy in patients with metastatic and/or advanced breast cancer with different toxicity profiles. Capecitabine-based chemotherapy may be better tolerated than capecitabine-free chemotherapy. Due to several limitations in our study, future large randomized trials are needed.