Treatment for anthracycline-pretreated metastatic breast cancer

Outcome and feasibility of palliative chemotherapy in very elderly patients with metastatic breast cancer

In the Netherlands, approximately 1300 women aged ≥75 years die every year of metastatic breast cancer (MBC). Data on palliative chemotherapy (CT) in very elderly patients are rare, and prospective studies appeared cumbersome. Therefore, we retrospectively analyzed the outcome and feasibility of chemotherapy in elderly MBC patients. Records of all patients with MBC aged ≥75 years who received first-line palliative chemotherapy between January 2000 and December 2014 at two large teaching hospitals in the Netherlands were reviewed. We registered patient and tumor characteristics together with data on previous adjuvant treatment, palliative endocrine treatment, comorbidities, clinical benefit (defined as ≥6 months progression-free survival), toxicity, and the reason for stopping chemotherapy. Patients with progressive disease (PD) or death within 30 days after starting CT were censored from analysis. A total of 54 patients with a median age of 77.6 years (range 75-90) were treated with palliative chemotherapy for MBC. Of them, 20 patients (37%) were aged ≥ 80 years. There was clinical benefit in 28 patients (52%). Median progression-free survival and median overall survival were 6.0 and 14.0 months, respectively. One year after the diagnosis of MBC, 27 patients (50%) were still alive and 15 patients (28%) lived longer than 2 years. Reasons for stopping CT were progressive disease (n = 32) or toxicity (n = 13). Most patients (n = 48) died of MBC while two patients died of toxicity. In selected patients with MBC aged 75 years or older, single-agent palliative chemotherapy is feasible and may have clinical benefit.

Early diagnosis of cardiotoxic complications of chemotherapy: the possibility of radiation research methods

Oncological diseases are the main causes of death in the world. Modern treatment of cancer patients contributes to an increase in survival rate due to strong chemotherapeutic drugs, the use of which is accompanied by toxic effects on cardiomyocytes. The main manifestations of cardiotoxicity are left ventricular dysfunction, myocardial ischemia, thromboembolic complications, chronic heart failure. As a result, the risk of cardiovascular mortality may be higher than the risk of death from the tumor process. An important task of oncologists and cardiologists is the early diagnosis of cardiotoxic complications in order to start treatment in time and reduce mortality from cardiovascular pathology in cancer patients.

Cardioprotective Effects of Carvedilol in Inhibiting Doxorubicin-induced Cardiotoxicity

PURPOSE

Anthracyclines (ANTs) are a class of active antineoplastic agents with topoisomerase-interacting activity that are considered the most active agents for the treatment of breast cancer. We investigated the efficacy of carvedilol in the inhibition of ANT-induced cardiotoxicity.

METHODS

In this randomized, single-blind, placebo-controlled study, 91 women with recently diagnosed breast cancer undergoing ANT therapy were randomly assigned to groups treated with either carvedilol (n = 46) or placebo (n = 45). Echocardiography was performed before and at 6 months after randomization, and absolute changes in the mean left ventricular ejection fraction, left ventricular end diastolic volume, and left ventricular end systolic volume were determined. Furthermore, the percentage change in the left atrial (LA) diameter and other variables of left ventricular (LV) diastolic function, such as transmitral Doppler parameters, including early (E wave) and late (A wave) diastolic velocities, E/A ratio and E wave deceleration time, pulmonary venous Doppler signals, including forward systolic (S wave) and diastolic (D wave) velocities into LA, late diastolic atrial reversal velocity, and early diastolic tissue Doppler mitral annular velocity (e') were measured. In addition, tissue Doppler mitral annular systolic (s') velocity, as a marker of early stage of LV systolic dysfunction, E/e' ratio, as a determinant of LV filling pressure, and troponin I level, as a marker of myocardial necrosis were measured.

RESULTS

At the end of follow-up period, left ventricular ejection fraction did not change in the carvedilol group. However, this parameter was significantly reduced in the control group (P < 0.001). Echocardiography showed that both left ventricular end systolic volume and LA diameter were significantly increased compared with the baseline measures in the control group. In pulse Doppler studies, pulmonary venous peak atrial reversal flow velocity was significantly increased in the control group. Moreover, a significant decrease in the mitral annuli early diastolic (e') and peak systolic (s') velocities and a significant increase in the E (the peak early diastolic velocity)/e' ratio in the control group were also observed. However, none of these variables were adversely changed at the end of follow-up in the carvedilol group. Furthermore, the TnI level was significantly higher in the control group than in the carvedilol group (P = 0.036) at 30 days after the initiation of chemotherapy.

CONCLUSIONS

Prophylactic use of carvedilol may inhibit the development of anthracycline-induced cardiotoxicity, even at low doses.

Cardioprotective Effect of Dexrazoxane in Patients with HER2-Positive Breast Cancer Who Receive Anthracycline Based Adjuvant Chemotherapy Followed by Trastuzumab

Purpose

We intended to determine whether dexrazoxane (DZR) is cardioprotective during administration of adjuvant anthracycline-based chemotherapy followed by a 1-year trastuzumab treatment.

Methods

The medical records of 228 patients who underwent surgical resection and received adjuvant chemotherapy with trastuzumab for human epidermal growth factor receptor type 2 (HER2)-positive breast cancer between January 2010 and December 2014 were reviewed. Approximately 25% of patients received DZR prior to each administration of doxorubicin during doxorubicin with cyclophosphamide (AC) chemotherapy. DZR was not administered during the 1-year trastuzumab maintenance period. Rates of cardiac events (reduction in left ventricular ejection fraction [LVEF] by 10% or more; reduction in absolute LVEF to <45%) and cardiac event-free duration (CFD) were examined. The trastuzumab interruption rate was also assessed.

Results

Twelve percent of patients experienced a cardiac event. Repeated-measures analysis of variance for ejection fraction revealed a significant main effect of time, and a significant group (DZR)×time interaction. The group treated with adjuvant chemotherapy and DZR experienced significantly lower frequencies of cardiac events than the adjuvant chemotherapy only group. In multivariate analysis, DZR administration was associated with significantly fewer cardiac events. Moreover, DZR administration was an independent good prognostic factor for CFD. Only one patient (2.3%) experienced early interruption of trastuzumab in the adjuvant chemotherapy with DZR group due to cardiac toxicity, whereas 10 patients (7.6%) experienced a trastuzumab stop event in the adjuvant chemotherapy only group.

Conclusion

DZR is cardioprotective in HER2-positive breast cancer patients who received adjuvant chemotherapy with trastuzumab. A large cohort randomized trial is needed to determine if DZR has an effect on trastuzumab interruption and completion of 12-month trastuzumab. Because cardiac toxicity has a significant negative effect on trastuzumab maintenance and quality of life, DZR administration could be considered concomitantly with anthracycline-based adjuvant chemotherapy with trastuzumab.

A network-based phenotype mapping approach to identify genes that modulate drug response phenotypes

To better address the problem of drug resistance during cancer chemotherapy and explore the possibility of manipulating drug response phenotypes, we developed a network-based phenotype mapping approach (P-Map) to identify gene candidates that upon perturbed can alter sensitivity to drugs. We used basal transcriptomics data from a panel of human lymphoblastoid cell lines (LCL) to infer drug response networks (DRNs) that are responsible for conferring response phenotypes for anthracycline and taxane, two common anticancer agents use in clinics. We further tested selected gene candidates that interact with phenotypic differentially expressed genes (PDEGs), which are up-regulated genes in LCL for a given class of drug response phenotype in triple-negative breast cancer (TNBC) cells. Our results indicate that it is possible to manipulate a drug response phenotype, from resistant to sensitive or vice versa, by perturbing gene candidates in DRNs and suggest plausible mechanisms regulating directionality of drug response sensitivity. More important, the current work highlights a new way to formulate systems-based therapeutic design: supplementing therapeutics that aim to target disease culprits with phenotypic modulators capable of altering DRN properties with the goal to re-sensitize resistant phenotypes.

Epirubicin inhibits growth and alters the malignant phenotype of the U‑87 glioma cell line

Epirubicin, an anthracycline derivative, is one of the main line treatments for brain tumors. The aim of the present study was to verify that epirubicin alters the growth and morphological characteristics of U‑87 glioma cells. In the present study, the effects of epirubicin were tested using cellular and biochemical assays, which demonstrated its anti‑proliferative and cytotoxic effects, with an IC50 of 6.3 µM for the U‑87 cell line, while rat normal neuronal cells were resistant to epirubicin. Epirubicin also reduced the secretion of matrix metalloproteinase‑9 by 48 and 56% at concentrations of 2.5 and 5 µM, respectively. Exposure to epirubicin also diminished levels of vascular endothelial growth factor in U‑87 cells. Furthermore, a cell migration assay showed a significant decrease in cell migration from 28 to 59% following exposure to 1 µM epirubicin. The present study demonstrated the cytotoxic, anti‑proliferative and anti‑migrative potential of epirubicin against glioma cells in vitro.

Dexrazoxane protects breast cancer patients with diabetes from chemotherapy-induced cardiotoxicity

BACKGROUND

To evaluate the cardioprotective effect of dexrazoxane (DEX) on chemotherapy in patients with breast cancer with concurrent type 2 diabetes mellitus (DM2).

METHODS

Eighty female patients with breast cancer with DM2 were randomly assigned to receive chemotherapy only or chemotherapy plus DEX. All patients received 80 mg/m epirubicin and 500 mg/m cyclophosphamide by intravenous infusion every 3 weeks for a total of 6 cycles. The group assigned to receive chemotherapy alone received placebo 30 minutes before epirubicin administration. The group assigned to receive chemotherapy plus DEX received 800 mg/m DEX 30 minutes before epirubicin administration. Cardiac function and hematology before and after 6 cycles of chemotherapy were analyzed.

RESULTS

There was no difference in baseline systole or diastole function between the 2 DM2 groups. Patients receiving chemotherapy alone experienced significantly greater reductions in Ea and significantly greater elevations in E/Ea and Tei index in comparison with patients receiving chemotherapy plus DEX. After chemotherapy, superoxide dismutase was significantly reduced, and serum malondialdehyde (MDA) was significantly increased in patients with DM2. Serum superoxide dismutase levels were comparable between the 2 groups before and after chemotherapy, MDA levels were comparable between the 2 groups before chemotherapy, whereas serum MDA was significantly higher after chemotherapy in the chemotherapy alone group in comparison with the group that received DEX.

CONCULSIONS

DEX protects against cardiotoxicity induced by chemotherapy in patients with breast cancer with concurrent DM2.

Multicenter experience of nonpegylated liposomal doxorubicin use in the management of metastatic breast cancer

BACKGROUND

This study aimed to investigate the use of nonpegylated liposomal doxorubicin (NPLD) in the management of metastatic breast cancer (MBC) within routine UK clinical practice and to assess its efficacy and tolerability.

PATIENTS AND METHODS

All patients that received NPLD for MBC at 5 institutions were identified. Clinicopathologic details, echocardiographic data, and toxicities were documented. Response to treatment, outcome, cardiotoxicity, and safety were assessed.

RESULTS

63 patients (median age at NPLD therapy, 53.5 years) who had received NPLD were identified; 18 (29%) were anthracycline-naïve, and 42 (67%) were anthracycline-pretreated (median cumulative dose of epirubicin, 450 mg/m(2)). In 3 cases, prior treatment history was not available. NPLD was most frequently (16 [25%] of 63 patients) administered as first-line chemotherapy (median, third-line; range, 1-9), although it was given later in anthracycline-pretreated patients (median, fourth-line; range, 1-9). Overall, 14 (29%) of 49 evaluable patients achieved an objective response, which increased to 10 (71%) of 14 when NPLD was given first-line (anthracycline-naïve, 8 [100%] of 8; anthracycline-pretreated, 2 [50%] of 4; adjuvant treatment unknown, 2). Median progression-free survival was 7 months (first-line, 18 months, vs. ≥ second-line, 6 months; P = .0066), and median overall survival was 10 months (first-line, 18 months, vs. ≥ second-line, 10 months; P = .0971). Toxicities tended to be grade 1 or 2. Three patients had cardiotoxicity (left ventricular ejection fraction < 50% or a fall of ≥ 10% from baseline), which resolved during treatment.

CONCLUSION

NPLD was used in both anthracycline-naïve patients and those with prior exposure. There is evidence of clinical activity in those with prior exposure to anthracyclines, with a low incidence of cardiotoxicity.

Doxorubicin induces protein ubiquitination and inhibits proteasome activity during cardiotoxicity

Anthracycline-induced cardiotoxicity is a clinically complex syndrome that leads to substantial morbidity and mortality for cancer survivors. Despite several years of research, the underlying molecular mechanisms remain largely undefined and thus effective therapies to manage this condition are currently non-existent. This study therefore aimed to determine the contribution of the ubiquitin-proteasome pathway (UPP) and endoplasmic reticulum (ER)-stress within this context. Cardiotoxicity was induced with the use of doxorubicin (DXR) in H9C2 rat cardiomyoblasts (3 μM) for 24 h, whereas the tumour-bearing GFP-LC3 mouse model was treated with a cumulative dose of 20 mg/kg. Markers for proteasome-specific protein degradation were significantly upregulated in both models following DXR treatment, however proteasome activity was lost. Moreover, ER-stress as assessed by increased ER load was considerably augmented (in vitro) with modest binding of DXR with ER. These results suggest that DXR induces intrinsic activation of the UPP and ER stress which ultimately contributes to dysfunction of the myocardium during this phenomenon.

Differential response of immunohistochemically defined breast cancer subtypes to anthracycline-based adjuvant chemotherapy with or without paclitaxel

Background

The aim of the present study was to investigate the efficacy of adjuvant dose-dense sequential chemotherapy with epirubicin, paclitaxel, and CMF in subgroups of patients with high-risk operable breast cancer, according to tumor subtypes defined by immunohistochemistry (IHC).

Materials and Methods

Formalin-fixed paraffin-embedded (FFPE) tumor tissue samples from 1,039 patients participating in two adjuvant dose-dense sequential chemotherapy phase III trials were centrally assessed in tissue micro-arrays by IHC for 6 biological markers, that is, estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki67, cytokeratin 5 (CK5), and EGFR. The majority of the cases were further evaluated for HER2 amplification by FISH. Patients were classified as: luminal A (ER/PgR-positive, HER2-negative, Ki67^low); luminal B (ER/PgR-positive, HER2-negative, Ki67^high); luminal-HER2 (ER/PgR-positive, HER2-positive); HER2-enriched (ER-negative, PgR-negative, HER2-positive); triple-negative (TNBC) (ER-negative, PgR-negative, HER2-negative); and basal core phenotype (BCP) (TNBC, CK5-positive and/or EGFR-positive).

Results

After a median follow-up time of 105.4 months the 5-year disease-free survival (DFS) and overall survival (OS) rates were 73.1% and 86.1%, respectively. Among patients with HER2-enriched tumors there was a significant benefit in both DFS and OS (log-rank test; p = 0.021 and p = 0.006, respectively) for those treated with paclitaxel. The subtype classification was found to be of both predictive and prognostic value. Setting luminal A as the referent category, the adjusted for prognostic factors HR for relapse for patients with TNBC was 1.91 (95% CI: 1.31–2.80, Wald's p = 0.001) and for death 2.53 (95% CI: 1.62–3.60, p<0.001). Site of and time to first relapse differed according to subtype. Locoregional relapses and brain metastases were more frequent in patients with TNBC, while liver metastases were more often seen in patients with HER2-enriched tumors.

Conclusions

Triple-negative phenotype is of adverse prognostic value for DFS and OS in patients treated with adjuvant dose-dense sequential chemotherapy. In the pre-trastuzumab era, the HER2-enriched subtype predicts favorable outcome following paclitaxel-containing treatment.

Treatment of metastatic breast cancer: second line and beyond

Increasing use of standard chemotherapy, especially anthracycline- and taxane-based therapies, in early-stage breast cancer has led to a corresponding increase in heavily pretreated and/or treatment-resistant cases of metastatic breast cancer (MBC). Thus, second and later lines of MBC therapy frequently involve the clinically challenging picture of progressive disease and limited treatment options. While several prognostic factors have been identified to aid treatment selection in MBC patients, treatment is palliative and aimed at prolonging survival, controlling symptoms, and maximizing patients' quality of life. No globally accepted standard exists for meeting these goals, and treatment patterns vary according to region. The list of available agents for the treatment of MBC is increasing with newer chemotherapeutic agents and molecular-targeted therapies. Within recent years, several single-agent and combination chemotherapy regimens have been shown to improve progression-free survival and reduce symptoms of disease in clinical studies in patients with resistant and/or heavily pretreated MBC. However, at present, the demonstrated benefits of these medical interventions have usually not included extension of overall survival times. It is hoped that in the near future, ongoing refinements to treatment approaches used in second-line settings and beyond will allow meaningful improvements in symptom control and survival in MBC.

Rechallenging with anthracyclines and taxanes in metastatic breast cancer

Adjuvant use of anthracycline-taxane combination therapy is an accepted strategy in the management of high-risk early-stage breast cancer. However, the introduction of this regimen raises the question of how best to manage those patients who relapse following adjuvant therapy, and whether there is a role for rechallenging in the metastatic setting with the same agent, or class of agent, that has been utilized in the adjuvant setting. This Review examines the evidence for rechallenging with both anthracyclines and taxanes, and highlights the issues that need to be examined in the context of future clinical trials.

Overall survival and post-progression survival in advanced breast cancer: a review of recent randomized clinical trials

With the availability of several lines of therapy, overall survival (OS) has been progressively substituted by progression-free survival (PFS) and other tumor-based assessments as the primary efficacy end point in advanced breast cancer trials. We investigated the frequency and determinants of OS gain in the recent literature and the duration of post-progression survival (PPS) according to treatment type and line. We used PubMed to search for phase III trials on systemic antineoplastic therapies published between January 1998 and December 2007 in 11 leading journals. The primary end point was the one stated explicitly, used for N calculation, or listed first. Significant gain was considered as reported P < .05 for superiority trials or proven non-inferiority or equivalence otherwise. We retrieved 76 trials, and gain in OS was reported in 15 cases (19.7%). The median gain in OS was 4.7 months, and such gain was more frequent when there was significant gain in PFS and in second-line and third-line trials. The average median OS was 20.7 months in trials assessing first-line chemotherapy and 31.1 months with first-line hormone therapy. The median proportion of OS accounted for by PPS was significantly longer in hormone therapy trials than in chemotherapy trials, but varied little across treatment lines. A statistically significant gain in OS has been reported in about one in five recent phase III trials in advanced breast cancer, despite the fact that OS has seldom been used as the primary end point. PPS represents nearly two thirds of patient survival after on-trial disease progression.

Gemcitabine and capecitabine in previously anthracycline-treated metastatic breast cancer: a multicenter phase II study (SOLTI 0301 trial)

BACKGROUND

On the basis of clinical activity of capecitabine and gemcitabine for metastatic breast cancer, we carried out a multicenter phase II clinical trial on the combination of these two agents in advanced anthracycline-pretreated breast cancer patients. Main objectives were to assess its efficacy and safety profile.

PATIENTS AND METHODS

Seventy-six anthracycline-pretreated breast cancer patients were evaluated and were stratified according to previous treatment of advanced disease (group-1: not previously treated and group-2: previously treated). Study treatment consisted of gemcitabine 1000 mg/m(2), i.v., as 30 min-infusion, days 1 and 8 every 21 days, plus oral capecitabine 830 mg/m(2) b.i.d., days 1-14 every 21 days.

RESULTS

Overall response rate was 61% for group-1, 48.5% for group-2 and 55.2% for the whole population. Clinical benefit rate was 73% for group-1, 80% for patients in group-2 and 76% for all patients. Median time to progression was 13.0 months for group-1, 8.2 months for group-2 and 11.1 months for the whole population. Most frequent grade 3-4 observed toxic effects per patient were neutropenia (60%), asymptomatic liver toxicity (13.5%), asthenia (14%) and hand-foot syndrome (16%). Only one patient presented febrile neutropenia. No treatment-related deaths occurred.

CONCLUSION

Combination of gemcitabine and capecitabine is an active and safe regimen in anthracycline-pretreated breast cancer patients.

Metastatic breast cancer: therapeutic options according to molecular subtypes and prior adjuvant therapy

In spite of advances in treatment strategies, about 25%-40% of patients with breast cancer still eventually develop metastatic disease that is largely incurable. Treatment goals vary from symptom control to lengthening survival, mainly on the basis of patient age and performance status, tumor biology, site and extent of disease, and prior therapies. In particular, breast cancer molecular characterization allows for the identification of breast cancer subtypes with distinct biological features, a distinct clinical course, and distinct treatment sensitivity. Endocrine manipulation is the cornerstone of therapy in hormone receptor-positive tumors; anti-human epidermal growth factor receptor (HER)-2 agents are essential in the management of HER-2(+) tumors; and chemotherapy is the only available option so far for the triple-negative subtype. In each of these subtypes, the more efficacious agents have been progressively incorporated into adjuvant treatment. As a consequence, the choice of the optimal therapeutic strategy for patients with metastatic disease is largely influenced by prior exposure to adjuvant therapies. This review contextualizes the data from clinical trials into different clinical scenarios of metastatic disease, taking into account the molecular subtype and prior adjuvant treatments.

Single agent versus combination chemotherapy for metastatic breast cancer

BACKGROUND

Combination chemotherapy regimens are frequently favoured over single agents for the treatment of metastatic breast cancer, in an attempt to achieve superior tumour response rates. It is not known however whether giving more intensive chemotherapy regimens results in better health outcomes, when both survival and toxicity are considered, and whether better response rates and rates of progression free survival actually translate to better overall survival.

OBJECTIVES

To compare single agent with combination chemotherapy for the treatment of metastatic breast cancer.

SEARCH STRATEGY

We searched the Cochrane Breast Cancer Group Specialised Register November 2008. Handsearching of recent conference proceedings was also undertaken.

SELECTION CRITERIA

Randomised trials of single agent chemotherapy compared to combination therapy in metastatic breast cancer.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for eligibility and quality, and extracted data. Hazard ratios were derived for reported time-to-event outcomes.Response rates were analysed as dichotomous variables. Toxicity and quality of life data were extracted where present.

MAIN RESULTS

Forty three eligible trials (48 comparisons) were identified. These included 9742 women, 55% of whom were receiving first-line treatment for metastatic disease. For overall survival there was a statistically significant difference in favour of the combination regimens with no heterogeneity (HR 0.88, 95% CI 0.83-0.93, p<0.00001). Results were very similar when trials of first-line treatment were analysed, and for analyses where the single agent was also included in the combination regimen. Combination regimens showed a statistically significant advantage for survival over single agent taxane (HR 0.82; 95% CI 0.75-0.89, p<0.00001), but not anthracycline (HR 0.94.86-1.02, p=0.15).Combination regimens were also associated with significantly better time to progression (HR 0.78, 95% CI 0.74 - 0.82, p<0.00001) and response (RR 1.29, 95% CI 1.14 -1.45, p<0.0001) although heterogeneity was statistically significant in both instances and probably due to clinical diversity of the participants and interventions.Women receiving combination regimens experienced a statistically significant detrimental effect on white cell count, increased alopecia and nausea and vomiting.

AUTHORS' CONCLUSIONS

Combination chemotherapy regimens show a statistically significant advantage for survival, tumor response and time to progression in women with metastatic breast cancer but they also produce more toxicity. An unresolved question is whether combination regimens are more effective than single agents given sequentially.

Expert opinion on the use of anthracyclines in patients with advanced breast cancer at cardiac risk

Anthracyclines are considered to be among the most active agents for the treatment of breast cancer. However, their use is limited by cumulative, dose-related cardiotoxicity. Such cardiotoxicity results in a permanent loss of cardiac myocytes and a progressive reduction in cardiac function following each subsequent dose of anthracycline. Initially, damage to the heart is subclinical; however, increasingly impaired cardiac function can result in cardiovascular symptoms, with serious cardiac injury resulting in chronic heart failure. Since the early detection and treatment of cardiotoxicity can reduce its clinical effects, it is important that oncologists are aware of these adverse effects and manage them appropriately. This review examines the risk factors for anthracycline-associated cardiotoxicity and offers recommendations on strategies to reduce the cardiotoxicity of anthracyclines in the management of patients with advanced breast cancer.

Granulocyte colony-stimulating factor protects cardiac mitochondria in the early phase of cardiac injury

Although granulocyte colony-stimulating factor (G-CSF) reportedly plays a cardioprotective role in several models of cardiac injury, clinical use of this drug in cardiac patients has been controversial. Here, we tested, in vivo and in vitro, the effect of G-CSF on cardiac mitochondria, which play a key role in determining cardiac cellular fate and function. Mild stimulation of C57/BL6 mice with doxorubicin (Dox) did not induce cardiac apoptosis or fibrosis but did induce damage to mitochondrial organization of the myocardium as observed through an electron microscope. Cardiac catheterization and echocardiography revealed that Dox did not alter cardiac systolic function or left ventricular size but did reduce diastolic function, an early sign of cardiac damage. Treatment with G-CSF attenuated significantly the damage to mitochondrial organization and rescued diastolic function. In an in vitro model for rat neonatal cardiomyocytes, a subapoptotic dose of Dox induced severe mitochondrial damage, including marked swelling of the cardiac mitochondria and/or decreased mitochondrial membrane potential. These mitochondrial changes were completely blocked by pretreatment with G-CSF. In addition, G-CSF dramatically improved ATP generation, which rescued Dox-impaired mitochondrial electron transport and oxygen consumption mainly through complex IV. These findings clearly indicate that G-CSF protects cardiac mitochondria, which are key organelles in the determination of cardiac cellular fate, in the early phase of cardiac injury.

Progression-free survival and time to progression as primary end points in advanced breast cancer: often used, sometimes loosely defined

BACKGROUND

The growing availability of active agents makes the development of novel therapies increasingly complex and the choice of end points critical. We assessed the frequency of use of efficacy end points in advanced breast cancer.

METHODS

We searched PubMed for randomized trials published between 2000 and 2007 in 10 leading medical journals. We abstracted data on progression-free survival (PFS), time to tumor progression (TTP), response rate (RR) and overall survival.

RESULTS

A total of 58 studies enrolled 23,371 assessable patients in 122 treatment arms. The primary end points most frequently used were RR and TTP (n=21 each), followed by PFS (n=14). In five of the trials using TTP as the primary end point, no definition of TTP was reported; in 13 of the other 16 cases, death was counted as an event, making TTP indistinguishable from PFS. Trials having PFS, TTP or time to treatment failure as the primary end point (n=36) had a higher mean number of patients than those using RR (P=0.061).

CONCLUSION

Investigators seem to be frequently using PFS and TTP interchangeably in advanced breast cancer. Such use of terms may lead to confusion when results of different trials are compared, and uniform use of definitions seems in order.

Achievements in systemic therapies in the pregenomic era in metastatic breast cancer

Over the last decades, the introduction of several new agents into clinical practice has significantly improved disease control and obtained some, albeit rare, survival benefits in metastatic breast cancer (MBC). Despite these results, the choice of treatment for the majority of patients is still empirically based, since the only two predictive factors with level 1 evidence for clinical use are hormonal receptor status for endocrine therapy and HER-2 status for trastuzumab therapy. Important improvements in the endocrine therapy of both pre- and postmenopausal women with hormone-responsive disease have been achieved. For premenopausal women, ovarian function suppression with luteinizing hormone-releasing hormone analogs combined with tamoxifen has become the standard treatment, although aromatase inhibitors plus ovarian function suppression are under evaluation. In postmenopausal patients, aromatase inhibitors have proved to be superior to standard endocrine therapies in either first- or second-line treatment and a novel antiestrogen compound, fulvestrant, has been introduced in clinical practice. Chemotherapy remains the treatment of choice for hormone unresponsive or resistant patients. Anthracyclines and taxanes have been used either alone or in combination as first-line chemotherapy, but with the more frequent use of these agents in the adjuvant setting, new standards are needed for first-line chemotherapy, and new and more efficacious treatments are required. In the subgroup of patients with tumors that overexpress HER-2, the use of trastuzumab alone or in combination with chemotherapy has modified the natural history of these tumors, even if only about one out of two patients obtains a clinical response. In this review we summarize the main achievements and the currently available treatment options for patients with MBC.

Capecitabine monotherapy: safe and effective treatment for metastatic breast cancer

Optimal management for metastatic breast cancer frequently involves cytotoxic chemotherapy. Over the years, several complex multidrug regimens have been developed that were based upon a rationale of synergistic antitumor activity and nonoverlapping toxicities. However, recently the clinical value of these complex regimens has been called into question as several drugs used alone (monotherapy) or in sequence (serial single agent) have been shown to be both efficacious and better tolerated. Capecitabine (an orally administered fluoropyrimidine carbamate) is one such agent that has been proven to be effective when used alone for metastatic breast cancer, metastatic colorectal cancer, and adjuvant colon cancer. In this review, published (or reported in abstract form) data examining various aspects of clinical response and tolerability with single-agent capecitabine for (primarily) first- and second-line metastatic breast cancer are examined. For the most part, response rates are comparable with those of the more complex regimens. Dose reductions from the labeled dose of 1,250 mg/m(2) twice daily are relatively common. Toxicities (following dose reductions if needed) are generally manageable, even by more frail patients. Elderly patients are more likely to have impaired renal function or be receiving warfarin treatment, and special attention to these factors is warranted. Nonetheless, the drug administered alone is a reasonable choice when single-agent chemotherapy is entertained as a treatment option for metastatic breast cancer, including in the first-line setting.

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

Capecitabine is an important drug in the therapeutic armamentarium for metastatic breast cancer. A comprehensive worldwide clinical trial program involving >10,000 patients with locally advanced and metastatic breast cancer has provided evidence for the current treatment strategies. On the basis of data demonstrating consistent activity across several trials in patients with heavily pretreated breast cancer, capecitabine was approved in the U.S. in 1998 for the treatment of patients with metastatic disease resistant to paclitaxel and anthracycline-containing therapy, with later European Union approval for single-agent capecitabine in the metastatic setting. Capecitabine plus docetaxel (XT) was approved by the U.S. Food and Drug Administration for the treatment of metastatic breast cancer in 2001 on the basis of the large phase III trial comparing XT with docetaxel alone, which showed a survival advantage for combination therapy compared with single-agent therapy. This was shortly followed by European approval for the combination in metastatic breast cancer. The clinical utility of capecitabine in the management of breast cancer is supported by its convenient oral dosing schedule and favorable safety profile, as well as its excellent clinical activity in primary and metastatic breast cancer. Recently, clinical trials have studied single-agent capecitabine as first-line treatment and evaluated other capecitabine-containing combinations with cytotoxic and novel targeted agents.

Capecitabine: Expanding Options for the Treatment of Patients with Early or Locally Advanced Breast Cancer

Capecitabine has proven efficacy in metastatic breast cancer, extending survival in combination with docetaxel and offering a favorable safety profile, including minimal myelosuppression and alopecia, as a single agent. It is therefore logical that capecitabine could build on the improved outcomes achieved with taxanes in early breast cancer. In the neoadjuvant setting, a phase III trial of capecitabine and docetaxel (XT) versus doxorubicin and cyclophosphamide (AC) showed that XT was more effective than AC in terms of clinical response rate and pathologic complete response rate, with a manageable safety profile. Other studies, including a phase III trial of capecitabine, epirubicin, and docetaxel, a phase III trial of capecitabine and vinorelbine, and several phase II studies of different regimens with capecitabine, have confirmed the high activity of neoadjuvant capecitabine, with acceptable safety. In the adjuvant setting, a Finnish phase III study (FinXX) of sequential XT followed by cyclophosphamide, epirubicin, and capecitabine versus docetaxel followed by 5-fluorouracil, epirubicin, and cyclophosphamide has shown favorable safety with lower doses of both capecitabine and docetaxel in the XT combination. Efficacy results from that trial are eagerly awaited. A large, ongoing trial program is continuing to explore the potential for capecitabine in the treatment of early breast cancer, looking at capecitabine-taxane combinations, capecitabine maintenance therapy, capecitabine for elderly patients, and sequential versus combination therapy, involving >20,000 patients.

Clinical Pharmacology Issues Relevant to the Dosing and Toxicity of Chemotherapy Drugs in the Elderly

Persons over the age of 65 years are the fastest growing segment of the U.S. population. In the next 30 years, they will comprise more than 20% of the population. Fifty percent of all cancers occur in this age group, and therefore, there is an expected rise in the total cancer burden. Data are becoming available that will better guide the use of chemotherapy in the older patient population. In this paper, information regarding age-related physiologic changes and their relationship to pharmacology, functional status, and hematopoiesis is presented. The adjuvant treatment of breast and colon cancer, as well as the primary therapy of aggressive non-Hodgkin lymphoma is reviewed. The treatment of more advanced breast, ovarian, and non-small cell lung cancer is also discussed.

Phase II Study of Pemetrexed in Patients Pretreated with an Anthracycline, a Taxane, and Capecitabine for Advanced Breast Cancer

BACKGROUND

This phase II study evaluated the efficacy, safety, and health outcomes of pemetrexed treatment in heavily pretreated patients with advanced breast cancer.

PATIENTS AND METHODS

Women with metastatic breast cancer, Karnofsky performance status > or = 70, and previous treatment with > or = 3 regimens containing anthracyclines, taxanes, and capecitabine were eligible. Pemetrexed 500 mg/m2 intravenous infusion was administered on day 1 of a 21-day treatment cycle.

RESULTS

Eighty patients were enrolled, and 60 received concurrent folic acid and vitamin B12 supplements per protocol amendment to minimize possible pemetrexed-related toxicity. The median numbers of cycles delivered were 3 for vitamin-supplemented patients and 2 for non-vitamin-supplemented patients. Regardless of vitamin supplementation, the overall response rate was 8% (95% CI, 3%-16.6%), stable disease was exhibited in 36% of patients, median time to disease progression was 2.9 months, and median survival was 8.2 months. Improvements in patient-reported symptoms ranged from 16.2% for pain intensity to 32.1% for nausea. Major grade 3/4 toxicities were hematologic, with grade 4 neutropenia in 10% of patients and grade 3 toxicities consisting primarily of neutropenia (29%) and leukopenia (21%). There were no clear trends of the effect of supplementation on toxicity.

CONCLUSION

Pemetrexed has modest antitumor activity and is well tolerated in heavily pretreated patients with breast cancer. Further evaluation of this multitargeted antifolate in advanced breast cancer is warranted.

Docetaxel plus cisplatin is effective for patients with metastatic breast cancer resistant to previous anthracycline treatment: a phase II clinical trial

Background

Patients with metastatic breast cancer (MBC) are frequently exposed to high cumulative doses of anthracyclines and are at risk of resistance and cardiotoxicity. This phase II trial evaluated the efficacy and toxicity of docetaxel plus cisplatin, as salvage chemotherapy in patients with MBC resistant to prior anthracyclines.

Methods

Patients with MBC that had progressed after at least one prior chemotherapy regimen containing anthracyclines received docetaxel 75 mg/m² followed by cisplatin 60 mg/m² every 3 weeks for a maximum of 6 cycles or until disease progression.

Results

Between Jan 2000 and May 2002, 24 patients with tumors primary resistant and 15 with secondary resistant disease were accrued. All 39 patients were evaluable for safety and 36 for efficacy. The objective response rate was 31% (95% CI, 16–45%) with 3 complete responses. The median time to disease progression was 7 months, and the median overall survival was 23 months (median follow-up of 41 months). Neutropenia was the most frequently observed severe hematologic toxicity (39% of patients), whereas asthenia and nausea were the most common non-hematologic toxicities. No treatment-related death was observed.

Conclusion

In conclusion, we found docetaxel plus cisplatin to be an active and safe chemotherapy regimen for patients with MBC resistant to anthracyclines.

Long-term survival of a patient with primarily chemo-resistant metastatic breast cancer treated with medroxyprogesterone acetate

The prognosis of breast cancer patients with liver metastases is extremely poor. Here we present the case of a 66-year-old female breast cancer patient with multiple liver metastases diagnosed 2 years after a radical modified mastectomy followed by adjuvant tamoxifen. At progression, anthracycline-based chemotherapy was administered, but a CT scan following two cycles of FEC (5-fluorouracil, epirubicin, cyclophosphamide) showed progression of the liver metastases. Chemotherapy was therefore switched to medroxyprogesterone acetate (MPA). After 3 months the patient's general status improved, and disease stabilization was observed at the next CT scan. A further 4 months of MPA treatment resulted in complete response of all liver lesions. Treatment with oral MPA was continued for 4 years. At present, 11 years after the diagnosis of metastatic liver involvement, the patient is alive, free of cancer, and fully ambulatory. Despite bulky visceral disease and chemoresistance, hormonal treatment with MPA resulted in a spectacular and long-lasting response.

Facts and Controversies in Systemic Treatment of Metastatic Breast Cancer

The management of metastatic breast cancer remains an important and controversial issue. The systemic therapy, comprising endocrine, cytotoxic and biological agents, can be administered sequentially or in combination. Few drugs or combinations provide a significant improvement in survival and, therefore, in the great majority of cases, treatment is given with a palliative intent. With the exception of first-line therapy, for which general agreement exists, currently there is no consensual standard of care. This review will summarize the current knowledge and outline the controversial issues related to systemic therapy of metastatic breast cancer, with emphasis on treatment tailoring. The potential role of tumor molecular profile(s) in the selection of patients that could benefit the most from each strategy/agent will be discussed.

Clinical studies of three oral prodrugs of 5-fluorouracil (capecitabine, UFT, S-1): a review

Although 5-fluorouracil (5-FU) was first introduced in 1957, it remains an essential part of the treatment of a wide range of solid tumors. 5-FU has antitumor activity against epithelial malignancies arising in the gastrointestinal tract and breast as well as the head and neck, with single-agent response rates of only 10%-30%. Although 5-FU is still the most widely prescribed agent for the treatment of colorectal cancer, less than one-third of patients achieve objective responses. Recent research has focused on the biomodulation of 5-FU to improve the cytotoxicity and therapeutic effectiveness of this drug in the treatment of advanced disease. As all the anticancer agents, 5-FU leads to several toxicities. The toxicity profile of 5-FU is schedule dependent. Myelotoxicity is the major toxic effect in patients receiving bolus doses. Hand-foot syndrome (palmar-plantar erythrodysesthesia), stomatitis, and neuro- and cardiotoxicities are associated with continuous infusions. Other adverse effects associated with both bolus-dose and continuous-infusion regimens include nausea and vomiting, diarrhea, alopecia, and dermatitis. All these reasons explain the need for more effective and less toxic fluoropyrimidines. In the first part of this review, we briefly present the metabolic pathways of 5-FU responsible for the efficacy and toxicity of this drug. This knowledge is also necessary to understand the target(s) of biomodulation. The second part is devoted to a review of the literature on three recent prodrugs of 5-FU, i.e., capecitabine, UFT (ftorafur [FTO] plus uracil), and S-1 (FTO plus 5-chloro-2,4-dihydroxypyridine plus potassium oxonate). The pharmacological principles that have influenced the development of these new drugs and our current knowledge of the clinical pharmacology of these new agents, focusing on antitumor activity and toxicity, are presented. The literature was analyzed until March 2002. This review is intended to be as exhaustive as possible since it was conceived as a work tool for readers wanting to go further.