The Role of Capecitabine in First‐Line Treatment for Patients with Metastatic Breast Cancer

Randomized Open Label Phase III Trial of Irinotecan Plus Capecitabine versus Capecitabine Monotherapy in Patients with Metastatic Breast Cancer Previously Treated with Anthracycline and Taxane: PROCEED Trial (KCSG BR 11-01)

Purpose

We investigated whether irinotecan plus capecitabine improved progression-free survival (PFS) compared with capecitabine alone in patients with human epidermal growth factor 2 (HER2) negative and anthracycline and taxane pretreated metastatic breast cancer (MBC).

Materials and Methods

A total of 221 patients were randomly assigned to irinotecan (80 mg/m², days 1 and 8) and capecitabine (1,000 mg/m² twice a day, days 1-14) or capecitabine alone (1,250 mg/m² twice a day, days 1-14) every 3 weeks. The primary endpoint was PFS.

Results

There was no significant difference in PFS between the combination and monotherapy arm (median, 6.4 months vs. 4.7 months; hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.63 to 1.11; p=0.84). In patients with triple-negative breast cancer (TNBC, n=90), the combination significantly improved PFS (median, 4.7 months vs. 2.5 months; HR, 0.58; 95% CI, 0.37 to 0.91; p=0.02). Objective response rate was numerically higher in the combination arm, though it failed to reach statistical significance (44.4% vs. 33.3%, p=0.30). Overall survival did not differ between arms (median, 20.4 months vs. 24.0 months; p=0.63). While grade 3 or 4 neutropenia was more common in the combination arm (39.6% vs. 9.0%), hand-foot syndrome was more often observed in capecitabine arm. Quality of life measurements in global health status was similar. However, patients in the combination arm showed significantly worse symptom scales especially in nausea/vomiting and diarrhea.

Conclusion

Irinotecan plus capecitabine did not prove clinically superior to single-agent capecitabine in anthracycline- and taxane-pretreated HER2 negative MBC patients. Toxicity profiles of the two groups differed but were manageable. The role of added irinotecan in patients with TNBC remains to be elucidated.

A phase I followed by a randomized phase II trial of two cycles carboplatin-olaparib followed by olaparib monotherapy versus capecitabine in BRCA1- or BRCA2-mutated HER2-negative advanced breast cancer as first line treatment (REVIVAL): study protocol for a randomized controlled trial

Background

Preclinical studies in breast cancer models showed that BRCA1 or BRCA2 deficient cell lines, when compared to BRCA proficient cell lines, are extremely sensitive to PARP1 inhibition. When combining the PARP1 inhibitor olaparib with cisplatin in a BRCA1-mutated breast cancer mouse model, the combination induced a larger response than either of the two compounds alone. Several clinical studies have investigated single agent therapy or combinations of both drugs, but no randomized clinical evidence exists for the superiority of carboplatin-olaparib versus standard of care therapy in patients with BRCA1- or BRCA2--mutated metastatic breast cancer.

Methods/design

This investigator-initiated study contains two parts. Part 1 is a traditional 3 + 3 dose escalation study of the carboplatin-olaparib combination followed by olaparib monotherapy. The carboplatin dose will be escalated from area under the curve (AUC) 3 to AUC 4 with an olaparib dose of 25 mg BID. Olaparib is subsequently escalated to 50, 75, and 100 mg BID until >1/6 of patients develop dose-limiting toxicity (DLT). The dose level below will be the maximum tolerable dose (MTD). It is expected that 15–20 patients are needed in Part I.

In Part 2 BRCA1- or BRCA2-mutated HER2-negative breast cancer patients will be randomized between standard capecitabine 1250 mg/m² BID day 1–14 q day 22, versus 2 cycles carboplatin-olaparib followed by olaparib monotherapy 300 mg BID. In total 104 events in 110 patients need to be observed to detect a 75 % clinically meaningful improvement in progression-free survival (PFS), from a median of 4 months (control) to 7 months (experimental) assuming a 2-year accrual and ≥6 months of follow-up with 80 % power (5 %, two-sided significance level). After progression on first line treatment, patients will receive physician’s best choice of paclitaxel, vinorelbine, eribulin, or capecitabine (experimental arm only) at standard dose. A compassionate use program of olaparib is available for patients in the standard arm after progression on second line treatment.

Discussion

Results might be pivotal for registration of olaparib as standard first line treatment in advanced BRCA1- or BRCA2-mutated breast cancer.

Trial registration

ClinicalTrials.gov identifier: NCT02418624. Registered on 9 March 2015. EudraCT number: 2013-005590-41. Registered on 15 October 2014. Protocol version 3.0.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1423-0) contains supplementary material, which is available to authorized users.

Real-World Analysis of Medical Costs and Healthcare Resource Utilization in Elderly Women with HR+/HER2- Metastatic Breast Cancer Receiving Everolimus-Based Therapy or Chemotherapy

INTRODUCTION

The objective of this study was to analyze medical costs and healthcare resource utilization (HRU) associated with everolimus-based therapy or chemotherapy among elderly women with hormone-receptor-positive, human-epidermal-growth-factor-receptor-2-negative (HR+/HER2-) metastatic breast cancer (mBC).

METHODS

Elderly women (≥65 years) with HR+/HER2- mBC who failed a non-steroidal-aromatase-inhibitor and subsequently began a new line of treatment with everolimus-based therapy or chemotherapy for mBC (index therapy) during July 20, 2012 to March 31, 2014 were identified from two large commercial claims databases. All-cause, BC-, and adverse event (AE)-related medical costs (2014 USD), and all-cause and AE-related HRU per patient per month (PPPM) were compared between patients treated with everolimus-based therapy and chemotherapy across their first four lines of therapy for mBC. Adjusted costs and HRU differences were estimated by pooling all lines and using multivariable models adjusted for differences in patient characteristics.

RESULTS

In total, 925 elderly patients (mean age approximately 73 years) with HR+/HER2- mBC met the inclusion criteria; 230 received everolimus-based therapy (240 lines) and 737 received chemotherapy (939 lines). Compared with chemotherapy, everolimus-based therapy was associated with significantly lower total all-cause PPPM medical services costs (adjusted mean difference: $4007), driven by lower inpatient ($1994) and outpatient ($1402) costs; lower BC-related medical services costs ($3129), driven by both BC-related inpatient ($1883) and outpatient costs ($913); and lower AE-related medical services costs ($1873; all P < 0.01). Additionally, compared to patients treated with chemotherapy, patients treated with everolimus-based therapy had fewer all-cause outpatient visits (adjusted incidence rate ratio = 0.69), BC-related outpatient visits (0.66), other-medical-service visits (0.65), and AE-related HRU (0.59), which was driven by significantly fewer AE-related outpatient visits (0.56; all P < 0.01). Subgroup analyses comparing medical costs of everolimus-based therapy with capecitabine monotherapy showed consistent results overall.

CONCLUSION

This retrospective claims database analysis of elderly women with HR+/HER2- mBC in the United States showed that everolimus-based therapy was associated with significantly lower all-cause, BC-related, and AE-related medical services costs and less use of healthcare resources compared with chemotherapy.

FUNDING

Novartis.

Time on treatment of everolimus and chemotherapy among postmenopausal women with hormone-receptor-positive/human-epidermal-growth-factor-receptor-2-negative metastatic breast cancer: a retrospective claims study in the US

OBJECTIVE

This study aimed to compare time on treatment (TOT) among patients treated with everolimus and chemotherapy, two commonly used treatments for hormone-receptor-positive/human-epidermal-growth-factor-receptor-2-negative (HR+/HER2-) metastatic breast cancer (mBC).

METHODS

Postmenopausal women with HR+/HER2- mBC who initiated ≥1 new line of therapy for mBC during 20 July 2012-31 March 2014 after a non-steroidal aromatase inhibitor were identified from MarketScan and PharMetrics databases (2002Q1-2014Q2) using a claims-based algorithm. Patients were classified into treatment groups by regimen and line of therapy, and were followed until discontinuation of therapy, end of insurance eligibility, or data cut-off (30 June 2014). Discontinuation was defined as a treatment gap of ≥60 days; patients who did not discontinue were censored at the end of follow-up. TOT was compared between everolimus, chemotherapy, and capecitabine monotherapy using Kaplan-Meier analyses and multivariable Cox models adjusting for line of therapy, age, insurance, de novo mBC diagnosis, prior use of chemotherapy for mBC, sites of metastases, and Charlson comorbidity index.

RESULTS

Across the first four lines of therapies for mBC, a total of 940 everolimus, 3410 chemotherapy, and 721 capecitabine monotherapy regimens were included. Based on the different lines of therapies, the median TOT ranged from 5.5 to 7.2 months for everolimus, 4.3 to 4.7 months for chemotherapy, and 3.5 to 6.0 months for capecitabine monotherapy. Pooling all lines of therapies, everolimus was associated with significantly longer TOT compared to chemotherapy (multivariable-adjusted hazard ratio [HR] = 0.69, 95% confidence interval [CI]: 0.62-0.76) or capecitabine monotherapy (multivariable-adjusted HR = 0.73, 95% CI: 0.64-0.83). Longer TOT was consistently observed for everolimus for each line of therapy.

LIMITATIONS

Proxies used for identifying HR + /HER2- mBC and treatment line, lack of certain clinical factors in claims data, generalizability limited to commercially insured patients in the US.

CONCLUSIONS

This study found that HR+/HER2- mBC patients receiving everolimus experienced significantly longer TOT than those receiving chemotherapy overall or capecitabine monotherapy.

Health-related quality of life in patients with locally advanced or metastatic breast cancer treated with eribulin mesylate or capecitabine in an open-label randomized phase 3 trial

The clinical benefit of eribulin versus capecitabine was evaluated using health-related quality of life (HRQoL) data from a phase 3 randomized trial in patients with pretreated advanced/metastatic breast cancer (ClinicalTrials.gov identifier: NCT00337103). The study population has been described previously (Kaufman et al. in J Clin Oncol 33:594–601, 2015). Eligible patients received eribulin (1.4 mg/m² intravenously on days 1 and 8) or capecitabine (1.25 g/m² orally twice daily on days 1–14) per 21-day cycles. HRQoL was assessed using the European Organisation for Research and Treatment of Cancer (EORTC) Quality-of-life Questionnaire-Core 30 questions (QLQ-C30) and breast module-23 questions (QLQ-BR23), administered at baseline through 24 months, until disease progression or other antitumor treatment initiation. Minimally important difference (MID) and time to symptom worsening (TSW) were investigated. 1062 (96.4 %) Patients completed the EORTC questionnaire at baseline; overall, compliance was ≥80 %. Patients receiving capecitabine versus eribulin had significantly worse symptoms (higher scores) for nausea/vomiting (MID 8; P < 0.05) and diarrhea (MID 7; P < 0.05). Treatment with eribulin versus capecitabine, led to worse systemic therapy side-effects (dry mouth, different tastes, irritated eyes, feeling ill, hot flushes, headaches, and hair loss; MID 10; P < 0.01). Clinically meaningful worsening was observed for future perspective (MID 10; P < 0.05) with capecitabine and for systemic therapy side-effects scale (MID 10; P < 0.01) with eribulin. Patients receiving capecitabine experienced more-rapid deterioration in body image (by 2.9 months) and future perspective (by 1.4 months; P < 0.05) compared with those on eribulin; the opposite was observed for systemic side-effects where patients receiving eribulin experienced more-rapid deterioration than those receiving capecitabine (by 2 months; P < 0.05). Eribulin and capecitabine were found to have similar impact on patient functioning with no overall difference in HRQoL. Patients receiving eribulin reported worse systemic side-effects of chemotherapy but reduced gastrointestinal toxicity compared with capecitabine.

Clinical efficacy of administering oxaliplatin combined with S-1 in the treatment of advanced triple-negative breast cancer

Triple-negative breast cancer (TNBC) is not amenable to current targeted therapies and carries a poor prognosis; however, a specific systemic regimen cannot yet be recommended. The optimal duration of oxaliplatin (OXA) and S-1 combinatorial chemotherapy in patients with advanced breast cancer is not currently known and is likely to be patient-specific based on efficacy and toxicity. In the present study, 52 patients with advanced TNBC received OXA and S-1 chemotherapy. The efficacy and toxicity were observed. The results showed that the median number of regimens was 4 (range 2-6). The therapeutic efficacy was evaluated in all patients. The complete response, partial response, overall response and disease control rates were 3.8, 30.8, 34.6 and 69.2%, respectively. Four patients were lost to follow-up, and the median follow-up time was 13.7 months. The median progression-free survival time was 6.7 months [95% confidence interval (CI), 4.5-9.0] and the median overall survival (OS) time was 13.3 months (95% CI, 9.1-17.5). From the subgroup analysis, it was found that the median OS time of patients with stage IV disease and ≥2 metastases was significantly shorter than that of patients with stage IIIC disease and only 1 metastasis [11.3 vs. 22.7 months, P=0.010 (stage IV vs. stage IIC); 11.3 vs. 15.7 months, P=0.048 (≥2 vs. 1 metastasis)]. The main grade 3/4 toxic effects were neutropenia (11.5%), nausea (7.7%) and nerve toxicity (3.8%). The other toxic effects were mainly of grades 1-2 and included diarrhea, liver dysfunction, stomatitis, anemia and hand-foot syndrome. In conclusion, OXA combined with S-1 is an effective and tolerable regimen for the treatment of patients with advanced TNBC.

Newer therapies for the treatment of metastatic breast cancer: a clinical update

Breast cancer is the foremost common malignancy among the female population around the world. Female breast cancer incidence rates have increased since 1980, slowed in 1990, the rate of increase have leveled off since 2001. In spite of the advances in the early detection, treatment, surgery and radiation support, almost 70% of the patients develop metastasis and die of the disease. Around 10% of the patients when diagnosed with breast cancer have metastases. Survival among the breast cancer patients have increased due to the introduction of novel single agent, combination of chemotherapeutic agents and targeted biologic agents, which is breast cancer specific. The staging of tumor-node-metastasis is significant for the prognosis and treatment. Predominantly the combination of chemotherapeutic regimen is given to improve the rate of clinical benefit and the overall survival rate. Novel mono-therapeutic options are being used often in metastatic setting as they will not be able to endure the toxicity of the combination regimen. Usually, endocrine therapy is recommended for hormone-responsive breast cancer due to efficacy and favorable side effect profile but chemotherapy becomes an option when endocrine therapy fails. This review summarizes the newer therapeutic options for early breast cancer and advanced breast cancer that are pretreated heavily on other chemotherapeutic agents. Further it provides monotherapies and other emerging novel combination regime which can be opted for first line or second line setting.

Comparison between doublet agents versus single agent in metastatic breast cancer patients previously treated with an anthracycline and a taxane: a meta-analysis of four phase III trials

AIM

To compare doublet agents with single agent as salvage treatment in metastatic breast cancer (MBC) patients pre-treated with an anthracycline and a taxane.

METHODS

We systematically searched for randomised clinical trials that compared doublet agents with single agent in MBC patients pre-treated with an anthracycline and a taxane. The primary end point was overall survival (OS). Secondary end points were progression-free survival, overall response rate and grade 3 or 4 toxicity. Data were extracted from the studies by two independent reviewers. The meta-analysis was performed by Stata version 10.0 software (Stata Corporation, College Station, TX, USA).

RESULTS

Four trials comprising 2373 patients were eligible for inclusion. Meta-analysis showed that there was significant improvement in progression-free survival (PFS) (hazard ratio (HR) 0.79, 95% confidence interval (CI) 0.72-0.86, P = 0.000) and overall response rate (risk ratio (RR) 1.47, 95%CI 1.13-1.91; p = 0.004) in doublet agents group, though the pooled HR for OS (HR 0.96, 95%CI 0.87-1.05; p = 0.356) showed no significant difference. Subgroup analysis also favoured capecitabine-based doublet agents therapy in terms of PFS (HR 0.77, 95%CI 0.70-0.86; p = 0.000) and overall response rate (ORR) (RR 1.65, 95%CI 1.06-2.56; p = 0.026), but gemcitabine-based doublet agents therapy gained no clinical benefits. There were more incidences of grade 3 or 4 anaemia (RR 1.610, 1.212-2.314, p = 0.01), neutropenia (RR 2.239, 1.231-4.071, p = 0.008), thrombocytopaenia (RR 2.401, 1.595-3.615, p = 0.000), fatigue (RR 2.333, 1.338-4.006, p = 0.000) and nausea and vomiting (RR 2.233, 1.558-3.199, p = 0.000) in the combination group. With regard to the risk of grade 3 or 4 stomatitis (RR 1.666, 0.818-3.392, p = 0.160), diarrhoea (RR 0.739, 0.542-1.008, p = 0.056) and hand-foot syndrome (RR 1.002, 0.835-1.203, p = 0.983), equivalent frequencies were found between the two groups.

CONCLUSION

Combination chemotherapy offered a significant improvement in PFS and ORR in patients with MBC pre-treated with an anthracycline and a taxane but did not benefit OS. With present available data from randomised clinical trials, we were still unable to clearly set the role of combination therapy in the treatment of MBC in this setting.

Triple-negative breast cancer: are we making headway at least?

The so-called triple-negative breast cancer, as defined by tumors that lack estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2) overexpression, has generated growing interest in recent years despite representing less than 20% of all breast cancers. These tumors constitute an important clinical challenge, as they do not respond to endocrine treatment and other targeted therapies. As a group they harbor an aggressive clinical phenotype with early development of visceral metastases and a poor long-term prognosis. While chemotherapy remains effective in triple-negative disease, research continues to further identify potential new targets based on phenotypical and molecular characteristics of these tumors. In this respect, the presence of a higher expression of different biomarkers including epidermal growth factor receptor, vascular endothelial growth factor receptor, fibroblast growth factor receptor and Akt activation has led to a proliferation of clinical trials assessing the role of inhibitors to these pathways in triple-negative tumors. Moreover, the described overlap between triple-negative and basal-like tumors, and the similarities with tumors arising in the BRCA1 mutation carriers has offered potential therapeutic avenues for patients with these cancers including poly (ADP-ribose) polymerase inhibitors and a focus on a higher sensitivity to alkylating chemotherapy agents. Results from these trials have shown some benefit in small subgroups of patients, even in single-agent therapy, which reflects the heterogeneity of triple-negative breast cancer and highlights the need for a further subclassification of these types of tumors for better prognosis identification and treatment individualization.

Capecitabine monotherapy: review of studies in first-line HER-2-negative metastatic breast cancer

The goals of treatment for metastatic breast cancer (MBC) are to prolong overall survival (OS) while maximizing quality of life, palliating symptoms, and delaying tumor progression. For many years, anthracyclines and taxanes have been the mainstay of treatment for MBC, but these agents are now commonly administered earlier in the course of the disease. A recent meta-analysis revealed adverse effects on OS and overall response rates in patients with MBC receiving first-line anthracycline-based chemotherapy following relapse on adjuvant chemotherapy. Noncrossresistant cytotoxic agents and combinations that combine high clinical activity and acceptable tolerability while being convenient for patients are therefore needed for the first-line treatment of MBC patients. Capecitabine has substantial antitumor activity in the first-line treatment of patients with MBC in prospective, randomized, phase II/III clinical trials as monotherapy and in combination with biologic and novel agents. First-line capecitabine monotherapy has a favorable safety profile, lacking myelosuppression and alopecia, and does not compromise the administration of further lines of chemotherapy. Capecitabine is suitable for long-term administration without the cumulative toxicity that can limit the prolonged use of other chemotherapy agents. Here, we review the available data on capecitabine as a single agent for first-line treatment of patients with human epidermal growth factor receptor 2-negative MBC.

Clinical Response of Metastatic Breast Cancer to Multi-targeted Therapeutic Approach: A Single Case Report

The present article describes the ongoing (partial) remission of a female patient (41 years old) from estrogen receptor (ER)-positive/progesterone receptor (PR)-negative metastatic breast cancer in response to a combination treatment directed towards the revitalization of the mitochondrial respiratory chain (oxidative phosphorylation), the suppression of NF-kappaB as a factor triggering the inflammatory response, and chemotherapy with capecitabine. The reduction of tumor mass was evidenced by a continuing decline of CA15-3 and CEA tumor marker serum levels and ¹⁸FDG-PET-CT plus magnetic resonance (MR) imaging. It is concluded that such combination treatment might be a useful option for treating already formed metastases and for providing protection against the formation of metastases in ER positive breast cancer. The findings need to be corroborated by clinical trials. Whether similar results can be expected for other malignant tumor phenotypes relying on glycolysis as the main energy source remains to be elucidated.

Ixabepilone plus capecitabine in metastatic breast cancer patients with reduced performance status previously treated with anthracyclines and taxanes: a pooled analysis by performance status of efficacy and safety data from 2 phase III studies

Patients with metastatic breast cancer (MBC) previously treated with anthracyclines and taxanes often have decreased performance status secondary to extensive tumor involvement. Here, we report the pooled analysis of efficacy and safety data from two similarly designed phase III studies to provide a more precise estimate of benefit of ixabepilone plus capecitabine in MBC patients with Karnofsky's performance status (KPS) 70-80. Across the studies, anthracycline/taxane-pretreated MBC patients were randomized to receive ixabepilone plus capecitabine or capecitabine alone. Individual patient data for KPS 70-80 subset (n = 606) or KPS 90-100 subset (n = 1349) from the two studies were pooled by treatment. Analysis included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and safety. In patients with reduced performance status (KPS 70-80), ixabepilone plus capecitabine was associated with improvements in OS (median: 12.3 vs. 9.5 months; HR, 0.75; P = 0.0015), PFS (median: 4.6 vs. 3.1 months; HR, 0.76; P = 0.0021) and ORR (35 vs. 19%) over capecitabine alone. Corresponding results in patients with high performance status (KPS 90-100) were median OS of 16.7 versus 16.2 months (HR, 0.98; P = 0.8111), median PFS of 6.0 versus 4.4 months (HR, 0.58; P = 0.0009), and ORR of 45 versus 28%. The safety profile of combination therapy was similar between the subgroups. Ixabepilone plus capecitabine appeared to show superior efficacy compared to capecitabine alone in MBC patients previously treated with anthracyclines and taxanes, regardless of performance status, with a possible OS benefit favoring KPS 70-80 patients (ClinicalTrials.gov identifiers: NCT00080301 and NCT00082433).

Vorinostat synergises with capecitabine through upregulation of thymidine phosphorylase

Background:

Potentiation of anticancer activity of capecitabine is required to improve its therapeutic index. In colorectal cancer (CRC) cells, we evaluated whether the histone deacetylase-inhibitor vorinostat may induce synergistic antitumour effects in combination with capecitabine by modulating the expression of thymidine phosphorylase (TP), a key enzyme in the conversion of capecitabine to 5-florouracil (5-FU), and thymidylate synthase (TS), the target of 5-FU.

Methods:

Expression of TP and TS was measured by real-time PCR, western blotting and immunohistochemistry. Knockdown of TP was performed by specific small interfering RNA. Antitumour activity of vorinostat was assessed in vitro in combination with the capecitabine active metabolite deoxy-5-fluorouridine (5′-DFUR) according to the Chou and Talay method and by evaluating apoptosis as well as in xenografts-bearing nude mice in combination with capecitabine.

Results:

Vorinostat induced both in vitro and in vivo upregulation of TP as well as downregulation of TS in cancer cells, but not in ex vivo treated peripheral blood lymphocytes. Combined treatment with vorinostat and 5′-DFUR resulted in a synergistic antiproliferative effect and increased apoptotic cell death in vitro. This latter effect was impaired in cells where TP was knocked. In vivo, vorinostat plus capecitabine potently inhibited tumour growth, increased apoptosis and prolonged survival compared with control or single-agent treatments.

Conclusions:

Overall, this study suggests that the combination of vorinostat and capecitabine is an innovative antitumour strategy and warrants further clinical evaluation for the treatment of CRC.

Management of metastatic breast cancer: monotherapy options for patients resistant to anthracyclines and taxanes

Resistance to chemotherapeutic agents is a significant obstacle to the effective treatment of metastatic breast cancer (MBC). Anthracycline- and taxane-based regimens are active as first-line treatment for MBC; however, MBC often progresses because of primary or acquired resistance to anthracyclines and taxanes. There are few options for the treatment of patients with anthracycline- and taxane-resistant or taxane-refractory MBC. This article reviews several single agents that have demonstrated activity as treatment for patients with MBC who progress during, or rapidly following, treatment with anthracyclines and taxanes. Results from clinical trials evaluating agents such as ixabepilone, albumin-bound paclitaxel, capecitabine, vinorelbine, pemetrexed, and irinotecan are presented. Single-agent capecitabine is approved for the treatment of patients after failure of anthracyclines and taxanes. Ixabepilone has demonstrated efficacy in patients with MBC resistant to multiple chemotherapeutic agents and is the only agent approved by the Food and Drug Administration as monotherapy for anthracycline-, taxane-, and capecitabine-resistant MBC. Improved treatment strategies and further evaluation of newer agents may reduce the current burden of treatment-resistant or treatment-refractory MBC.

Capecitabine in Addition to Anthracycline- and Taxane-Based Neoadjuvant Treatment in Patients With Primary Breast Cancer: Phase III GeparQuattro Study

Purpose

Capecitabine can be integrated either concomitantly or sequentially to anthracycline-plus-taxane–based regimens.

Patients and Methods

Patients with large operable or locally advanced tumors, with hormone receptor–negative tumors, or with receptor-positive tumors but also clinically node-positive disease were recruited to receive preoperatively four cycles of epirubicin plus cyclophosphamide (EC; epirubicin 90 mg/m2 and cyclophosphamide 600 mg/m2). Patients were then randomly assigned to four cycles of docetaxel (100 mg/m2), four cycles of docetaxel + capecitabine (TX; docetaxel 75 mg/m2 plus capecitabine 1,800 mg/m2), or four cycles of docetaxel (75 mg/m2) followed by four cycles of capecitabine (1,800 mg/m2; T-X). Patients with human epidermal growth factor receptor 2 (HER-2) –positive tumors received trastuzumab concomitantly with all cycles. Primary objectives were to assess the effect of docetaxel by comparing EC plus docetaxel versus EC plus TX and to assess the effect of duration by comparing EC plus TX versus EC plus T-X on pathologic complete response (pCR, without invasive/noninvasive breast tumor, regardless of nodal status) at surgery, irrespective of trastuzumab treatment.

Results

Of 1,509 patients starting EC, 1,421 were randomly assigned to docetaxel (n = 471), TX (n = 471), or T-X (n = 479). At surgery, pCR rates were 22.3%, 19.5%, and 22.3%, respectively; the difference for docetaxel (EC plus docetaxel v EC plus TX) was 2.8% (95% CI, −2.4% to 8.0%; P = .298).The difference for duration was −2.8% (95% CI, −8.0% to 2.4%; P = .298). Breast conservation rates were 70.1%, 68.4%, and 65.3%, respectively (P = .781 for docetaxel; P = .270 for duration). Concomitant but not sequential treatment with docetaxel was associated with more diarrhea; nail changes, and hand-foot-syndrome, but it was associated with less edema.

Conclusion

Adding capecitabine to or prolonging duration of neoadjuvant EC plus docetaxel does not result in higher efficacy at surgery.

The cytostatic activity of pyrimidine nucleosides is strongly modulated by Mycoplasma hyorhinis infection: Implications for cancer therapy

Nucleoside analogues are widely used as chemotherapeutic agents in the treatment of cancer. Several cancers are reported to be associated with mycoplasmas (i.e. Mycoplasma hyorhinis), which contain a number of nucleoside-metabolizing enzymes. Pyrimidine nucleoside analogues, such as 5-fluoro-2'-deoxyuridine (FdUrd), 5-trifluorothymidine (TFT) and 5-halogenated 2'-deoxyuridines can be degraded by thymidine phosphorylase (TP) to their inactive bases. We found in M. hyorhinis-infected MCF-7 breast carcinoma cells (MCF-7/HYOR) a mycoplasma-encoded TP that dramatically (20-150-fold) reduces the cytostatic activity of these compounds. The reduction in cytostatic activity could be fully restored in the presence of TPI (5-chloro-6-[1-(2-iminopyrrolidinyl)methyl]uracil hydrochloride), a known inhibitor of human TP. This observation is in agreement with the markedly decreased formation of active metabolite (i.e. FdUMP for FdUrd) or diminished drug incorporation into nucleic acids (i.e. for TFT and 5-bromo-2'-deoxyuridine) in MCF-7/HYOR cells compared with uninfected MCF-7 cells. Antimetabolite formation is fully restored in the presence of TPI. In contrast, 5-fluoro-5'-deoxyuridine (5'DFUR), an intermediate metabolite of capecitabine, was markedly more cytostatic in MCF-7/HYOR cells than in uninfected cells, due to the activation of this prodrug by the mycoplasma-encoded TP. Thus, our data reveal that M. hyorhinis expresses a TP that activates 5'DFUR but inactivates FdUrd, TFT and 5-halogenated 2'-deoxyuridines, and that is highly sensitive to the inhibitory effect of the TP inhibitor TPI. Given the association of M. hyorhinis with several human cancers, our findings suggest that pyrimidine nucleoside-based but not 5FU-based anti-cancer therapy might be more effective when combined with a mycoplasmal TP inhibitor.

Anti-tumor activity of capecitabine and vinorelbine in patients with anthracycline- and taxane-pretreated metastatic breast cancer: findings from the EORTC 10001 randomized phase II trial

The aim of this randomized phase II study was to evaluate the anti-tumor activity and safety of capecitabine and vinorelbine in patients with metastatic breast cancer pretreated with taxanes and anthracyclines. We planned to randomize 72 patients to capecitabine 1250 mg/m(2) orally bid days 1-14 or vinorelbine 30 mg/m(2) i.v. days 1 and 8, both given every 3 weeks. The study was stopped due to poor accrual with 47 patients enrolled. Responses were seen in 2/23 patients treated with capecitabine (8.7%; 95% CI 1.1-29.0) and 3/24 patients treated with vinorelbine (12.5%; 95% CI 2.7-32.4). Median progression-free survival was 2.8 and 2.6 months, and median overall survival was 9.3 and 11.0 months, in the capecitabine and vinorelbine arms, respectively. There was more hematologic toxicity, neurotoxicity, and nausea/vomiting with vinorelbine and more diarrhea and hand-foot syndrome with capecitabine. The anti-tumor activity of capecitabine and vinorelbine seems to be comparable, but the toxicity profiles are different.

Targeting platelet-derived endothelial cell growth factor/thymidine phosphorylase for cancer therapy

Thymidine phosphorylase (TP) is a key enzyme in the pyrimidine nucleoside salvage pathway, but it also recognizes and inactivates various anti-cancer chemotherapeutic agents. Moreover, TP is identical to platelet-derived endothelial cell growth factor (PD-ECGF), an angiogenic factor with anti-apoptotic properties. Increased expression of PD-ECGF/TP is found in many tumor and stromal cells, and elevated TP levels are associated with aggressive disease and/or poor prognosis. Thus, progression and metastasis of TP-expressing tumors might be abrogated by TP inhibitors that are used as single agents or in combination with (TP-sensitive) nucleoside analogues. On the other hand, increased TP activity in tumors may be exploited for the tumor-specific activation of fluoropyrimidine prodrugs, such as capecitabine. This review will focus on the different biological activities of PD-ECGF/TP and their implications for cancer progression and treatment.