Venous thromboembolism and mortality associated with recombinant erythropoietin and darbepoetin administration for the treatment of cancer-associated anemia

Targeting the hepcidin-ferroportin axis to develop new treatment strategies for anemia of chronic disease and anemia of inflammation

Anemia of chronic disease (ACD) or anemia of inflammation is prevalent in patients with chronic infection, autoimmune disease, cancer, and chronic kidney disease. ACD is associated with poor prognosis and lower quality of life. Management of ACD using intravenous iron and erythropoiesis stimulating agents are ineffective for some patients and are not without adverse effects, driving the need for new alternative therapies. Recent advances in our understanding of the molecular mechanisms of iron regulation reveal that increased hepcidin, the iron regulatory hormone, is a key factor in the development of ACD. In this review, we will summarize the role of hepcidin in iron homeostasis, its contribution to the pathophysiology of ACD, and novel strategies that modulate hepcidin and its target ferroportin for the treatment of ACD.

Hematopoietic growth factors: personalization of risks and benefits

A common side effect of cancer treatment is bone marrow suppression. The resulting myelosuppression and anemia can cause significant morbidity and mortality for patients. Agents such as granulocyte colony stimulating factors (GCSF) and erythropoietin stimulating agents (ESAs) may be helpful to ameliorate this depression of blood counts; however these agents have risks which also need to be carefully weighed.

Erythropoietin receptor contributes to melanoma cell survival in vivo

Erythropoietin (Epo) is widely used clinically to treat anemia associated with various clinical conditions including cancer. Data from several clinical trials suggest significant adverse effect of Epo treatment on cancer patient survival. However, controversy exists whether Epo receptor (EpoR) is functional in cancer cells. In this study, we demonstrated that EpoR mRNA expression was detectable in 90.1% of 65 melanoma cell lines, and increased copy number of the Epo and EpoR loci occurred in 30 and 24.6% of 130 primary melanomas, respectively. EpoR knockdown in melanoma cells resulted in diminished ERK phosphorylation in response to Epo stimulation, decreased cell proliferation and increased response to the inhibitory effect of hypoxia and cisplatin in vitro. EpoR knockdown significantly decreased melanoma xenograft size and tumor invasion in vivo. On the contrary, constitutive activation of EpoR activated cell proliferation pathways in melanoma cells and resulted in increased cell proliferation and resistance to hypoxia and cisplatin treatment in vitro. EpoR activation resulted in significantly larger xenografts with increased tumor invasion of surrounding tissue in vivo. Daily administration of recombinant Epo fails to stimulate melanoma growth in vivo, but the treatment increased vascular size in the xenografts. Increased local recurrence after excision of the primary tumors was observed after Epo treatment. Epo induced angiogenesis in Matrigel plug assays, and neutralization of Epo secreted by melanoma cells results in decreased angiogenesis. These data support that EpoR is functional in melanoma and EpoR activation may promote melanoma progression, and suggest that Epo may stimulate angiogenesis and increase survival of melanoma cells under hypoxic condition in vivo.

Novel therapies in acute and chronic heart failure

Despite past advances in the pharmacological management of heart failure, the prognosis of these patients remains poor, and for many, treatment options remain unsatisfactory. Additionally, the treatments and clinical outcomes of patients with acute decompensated heart failure have not changed substantially over the past few decades. Consequently, there is a critical need for new drugs that can improve clinical outcomes. In the setting of acute heart failure, new inotrops such as cardiac myosin activators and new vasodilators such as relaxin have been developed. For chronic heart failure with reduced ejection fraction, there are several new approaches that target multiple pathophysiological mechanism including novel blockers of the renin-angiotensin-aldosterone system (direct renin inhibitors, dual-acting inhibitors of the angiotensin II receptor and neprilysin, aldosterone synthase inhibitors), ryanodine receptor stabilizers, and SERCA activators. Heart failure with preserved ejection fraction represents a substantial therapeutic problem as no therapy has been demonstrated to improve symptoms or outcomes in this condition. Newer treatment strategies target specific structural and functional abnormalities that lead to increased myocardial stiffness. Dicarbonyl-breaking compounds reverse advanced glycation-induced cross-linking of collagen and improve the compliance of aged and/or diabetic myocardium. Modulation of titin-dependent passive tension can be achieved via phosphorylation of a unique sequence on the extensible region of the protein. This review describes the pathophysiological basis, mechanism of action, and available clinical efficacy data of drugs that are currently under development. Finally, new therapies for the treatment of heart failure complications, such as pulmonary hypertension and anemia, are discussed.

The health-related quality of life was not improved by targeting higher hemoglobin in the Normal Hematocrit Trial

The Normal Hematocrit Trial (NHT) was the largest trial of epoetin randomizing 1265 hemodialysis patients with cardiac disease to lower (9-11 g/dl) or higher (13-15 g/dl) hemoglobin (Hgb), hypothesizing that higher Hgb would reduce mortality, and improve survival and quality of life. The trial was terminated early, and a 1998 publication reported that targeting higher hematocrit levels led to an insignificant increase in the primary end points (death or myocardial infarct), or risk ratio 1.3, 95% confidence interval (CI), 0.9-1.90, but the P-value was not given, and all-cause death risk was not reported. A higher target reportedly did not increase hospitalization rates, but did significantly improve the 'physical function' domain of quality of life. Comparing the 1996 Food and Drug Administration (FDA)-filed clinical trial report to the 1998 publication, however, found several discrepancies. Among these, the 1998 article reported interim trial results with only the adjusted CI but did not state that the unadjusted CIs were 99.912th percentile, and despite being a secondary end point, reported only the association of achieved Hgb with higher quality of life score. Randomization to the higher target had actually increased the risk for the primary end point (risk ratio 1.28, 95% CI=1.06-1.56; P=0.0112; 99.92% CI=0.92-1.78), the risk of death (risk ratio 1.27, 95% CI=1.04-1.54), non-access thrombotic events (P=0.041), and hospitalization rate (P=0.04), while 'physical function' did not improve (P=0.88). Hence, disclosure of these results in the 1998 publication or access to the FDA-filed report on the NHT in the late 1990s would likely have led to earlier concerns about epoetin safety and greater doubts about its benefits.

Effects of erythropoietin receptors and erythropoiesis-stimulating agents on disease progression in cancer

Erythropoiesis-stimulating agents (ESAs) increase red blood cell (RBC) production in bone marrow by activating the erythropoietin receptor (EpoR) on erythrocytic-progenitor cells. Erythropoiesis-stimulating agents are approved in the United States and Europe for treating anaemia in cancer patients receiving chemotherapy based on randomised, placebo-controlled trials showing that ESAs reduce RBC transfusions. Erythropoiesis-stimulating agent-safety issues include thromboembolic events and concerns regarding whether ESAs increase disease progression and/or mortality in cancer patients. Several trials have reported an association between ESA use and increased disease progression and/or mortality, whereas other trials in the same tumour types have not provided similar findings. This review thoroughly examines available evidence regarding whether ESAs affect disease progression. Both clinical-trial data on ESAs and disease progression, and preclinical data on how ESAs could affect tumour growth are summarised. Preclinical topics include (i) whether tumour cells express EpoR and could be directly stimulated to grow by ESA exposure and (ii) whether endothelial cells express EpoR and could be stimulated by ESA exposure to undergo angiogenesis and indirectly promote tumour growth. Although assessment and definition of disease progression vary across studies, the current clinical data suggest that ESAs may have little effect on disease progression in chemotherapy patients, and preclinical data indicate a direct or indirect effect of ESAs on tumour growth is not strongly supported.

Erythropoietin in brain development and beyond

Erythropoietin is known as the requisite cytokine for red blood cell production. Its receptor, expressed at a high level on erythroid progenitor/precursor cells, is also found on endothelial, neural, and other cell types. Erythropoietin and erythropoietin receptor expression in the developing and adult brain suggest their possible involvement in neurodevelopment and neuroprotection. During ischemic stress, erythropoietin, which is hypoxia inducible, can contribute to brain homeostasis by increasing red blood cell production to increase the blood oxygen carrying capacity, stimulate nitric oxide production to modulate blood flow and contribute to the neurovascular response, or act directly on neural cells to provide neuroprotection as demonstrated in culture and animal models. Clinical studies of erythropoietin treatment in stroke and other diseases provide insight on safety and potential adverse effects and underscore the potential pleiotropic activity of erythropoietin. Herein, we summarize the roles of EPO and its receptor in the developing and adult brain during health and disease, providing first a brief overview of the well-established EPO biology and signaling, its hypoxic regulation, and role in erythropoiesis.

Potential of Novel EPO Derivatives in Limb Ischemia

Erythropoietin (EPO) has tissue-protective properties, but it increases the risk of thromboembolism by raising the haemoglobin concentration. New generation of EPO derivatives is tissue protective without the haematopoietic side effects. Preclinical studies have demonstrated their effectiveness and safety. This paper summarizes the development in EPO derivatives with emphasis on their potential use in critical limb ischaemia.

Meta-analysis of randomized controlled trials for the incidence and risk of treatment-related mortality in patients with cancer treated with vascular endothelial growth factor tyrosine kinase inhibitors

PURPOSE

Vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) have become the cornerstone in the treatment of several malignancies. These drugs have also been associated with an increase in the risk of potentially life-threatening adverse events, such as arterial thrombotic events, bleeding, congestive heart failure, and others. We performed an up-to-date meta-analysis to determine the risk of fatal adverse events (FAEs) in patients with cancer treated with VEGFR TKIs.

METHODS

MEDLINE and PubMed databases were searched for articles published from January 1966 to February 2011. Eligible studies were limited to trials of US Food and Drug Administration-approved VEGFR TKIs (pazopanib, sunitinib, and sorafenib) that reported on patients with cancer with any primary tumor type, randomized design, and adequate safety profile. Statistical analyses were conducted to calculate the summary incidence, relative risk (RR), and 95% CIs by using random-effects or fixed-effects models on the basis of the heterogeneity of included studies.

RESULTS

In all, 4,679 patients from 10 randomized controlled trials (RCTs) were included, with 2,856 from sorafenib, 1,388 from sunitinib, and 435 from pazopanib trials. The incidence of FAEs related to VEGFR TKIs was 1.5% (95% CI, 0.8% to 2.4%) with an RR of 2.23 (95% CI, 1.12 to 4.44; P = .023) compared with control patients. On subgroup analysis, no difference in the rate of FAEs was found between different VEGFR TKIs or tumor types. No evidence of publication bias was observed.

CONCLUSION

In a meta-analysis of RCTs, the use of VEGFR TKIs was associated with an increased risk of FAEs compared with control patients.

Mortality associated with dose response of erythropoiesis-stimulating agents in hemodialysis versus peritoneal dialysis patients

BACKGROUND

Several studies have shown an association between erythropoietin-stimulating agent (ESA) responsiveness and mortality in chronic kidney disease (CKD) patients. In our present study, we examined the association between prescribed ESA dose and mortality in peritoneal dialysis (PD) and hemodialysis (HD) patients. We hypothesized that PD patients received lower ESA dose for the same achieved hemoglobin compared to HD patients and that ESA dose-mortality associations were different between PD and HD patients.

METHODS

We compared the prescribed doses of ESA between 139,103 HD and 10,527 PD patients treated in DaVita dialysis clinics from 7/2001 through 6/2006 using adjusted Poisson regression and examined mortality-predictability of prescribed ESA dose and ESA responsiveness index (ESA/hemoglobin) in PD and HD with follow-up through 6/2007 using Cox regression models.

RESULTS

Poisson adjusted ratio of ESA dose of HD to PD was 3.6 (95% CI 3.5-3.7). In PD patients, adjusted all-cause death hazard ratios (HR) for ESA doses of 3,000-5,999, 6,000-8,999 and ≥9,000 U/week (reference <3,000 U/week) were 0.97 (0.87-1.07), 0.85 (0.76-0.95) and 1.08 (0.98-1.18), respectively; whereas in HD patients across commensurate ESA dose increments of 10,000-19,999, 20,000-29,999 and ≥30,000 U/week (reference <10,000 U/week) were 1.14 (1.11-1.17), 1.54 (1.50-1.58) and 2.15 (2.10-2.21), respectively. In PD and HD patients, the adjusted death HR of the 4th to 1st quartile of ESA responsiveness index were 1.14 (1.04-1.26) and 2.37 (2.31-2.43), respectively.

CONCLUSIONS

Between 2001 and 2006, most PD patients received substantially lower ESA dose for same achieved hemoglobin levels, and low ESA responsiveness was associated with higher mortality in both HD and PD patients.

Risk management of biosimilars in oncology: each medicine is a work in progress

Drug licensing and drug safety monitoring for standard chemical entities have been established and are routinely used. These have resulted in a solid foundation of knowledge from which confident therapeutic decisions can be made. For many chemical entities, this advanced level of experience is also present for the generic products. The expertise surrounding the development of biosimilar competitor versions is increasing and progress is encouraging. To address the re-engineering and comparability complexities of biosimilars, the European Union imposed a requirement that risk management plans be included in the medications’ marketing applications. This paper summarizes and discusses the circumstances complicating the public’s view of drug safety, historical incidents during the transition from innovative to competitor products, as well as retrospective assessments of the development and post-marketing experiences thus far with two biosimilars. Through assessing the market entries and post-marketing experiences of biosimilars used in oncology, the healthcare field can better prepare for the next wave of comparator-products: biosimilar monoclonal antibodies.

Effects of funding policy changes and health warnings on the use of erythropoiesis-stimulating agents

PURPOSE

To characterize the effects of formulary changes and governmental safety warnings on use of erythropoiesis-stimulating agents (ESAs) in patients with cancer.

PATIENTS AND METHODS

We conducted a cross-sectional time-series analysis using health administrative data from Ontario, Canada. From January 1997 to December 2009 we identified all ESA initiations among patients diagnosed with cancer. We explored the effects of two formulary changes that progressively liberalized coverage for ESAs, first by rescinding the requirement for blood transfusion in 2003 and then by removing all restrictions in 2007. We also explored the effect of US Food and Drug Administration and Health Canada warnings issued in the second quarter of 2007. To assess regional variability in ESA use, we determined prescription rates for each of Ontario's 14 regional cancer centers.

RESULTS

After the first formulary change, the ESA initiation rate increased to 1.66 new users per 1,000 patients with cancer, 374% more than predicted (P < .001). After the second formulary change, the initiation rate increased to 3.97 new users per 1,000 patients with cancer, 73% more than predicted (P < .001). After the safety warnings, this rate declined 81% by study end (P < .001). We found significant regional variation in ESA use.

CONCLUSION

Formulary access and safety warnings had significant impacts on the new use of ESA drugs in patients with cancer. This suggests that both are effective means of influencing the use of these drugs. Variable ESA prescription rates across our region may reflect a lack of consensus regarding their utility.

Hematological changes during androgen deprivation therapy

Androgen deprivation therapy (ADT) has been associated with a plethora of adverse effects, consistent with the androgen dependency of multiple reproductive and somatic tissues. One such tissue is the hemopoietic system, and one of the most predictable consequences of ADT is the development of anemia. Although anemia caused by ADT is rarely severe, ADT is often given to frail, elderly men with increased susceptibility to anemia due to multiple other causes. ADT-associated anemia may contribute to fatigue and reduced quality of life (QoL) in such men, although this requires further study. While anemia is an independent risk factor of mortality in men with prostate cancer, it is not known whether treatment of ADT-associated anemia alters clinically important outcomes, or whether treatment affects mortality. Awareness of the phenomenon of ADT-induced anemia should avoid unnecessary work-up in mild cases of normocytic normochromic anemia. However, assessment and treatment of more severe anemia may be required. This should be determined on an individual basis. In contrast to the well-described actions of ADT on erythropoiesis, its effect on other hemopoietic lineages has been less well elucidated. While preclinical studies have found roles for androgens in maturation and differentiated function of neutrophils, lymphocytes and platelets, the implications of these findings for men with prostate cancer receiving ADT require further studies.

Evaluation of clinical use and effectiveness of darbepoetin alfa in cancer patients with chemotherapy-induced anemia

PURPOSE

To investigate the patterns of use of darbepoetin alfa in Spanish centers, and to evaluate its effectiveness in the treatment of chemotherapy-induced anemia under clinical practice conditions.

METHODS

This was an observational, retrospective, multicenter study in adult patients with non-myeloid malignancies who initiated chemotherapy and darbepoetin alfa. Data was collected for up to 16 weeks or until treatment discontinuation.

RESULTS

A total of 685 patients (72.7% with solid tumors and 27.3% with hematologic malignancies) were included in the study. Median age was 64.7 years (range 18.5-88.9 years), 50.7% were women, 82.4% had ECOG status 0-1 and 80.5% had stage III/IV cancer. At darbepoetin initiation, mean hemoglobin (Hb) was 100 g/L (SD 10), with 11.0% and 23.1% of patients below 90 g/L in solid and hematologic malignancies, respectively. A decrease in transfusion requirements was observed between weeks 5-16 with respect to weeks 0-16 (13.3% [95% CI: 10.7 to 15.9] versus 19.0% [95% CI: 16.0 to 22.0]). Hb levels were significantly increased during the treatment (mean change of 10.4 g/L for solid tumors [p < 0.001], and 16.6 g/L for hematologic malignancies [p < 0.001]). The percentage of patients with baseline Hb level <110 g/L who achieved an Hb level ≥110 g/L during the study was 66.5% (95% CI: 62.5% to 70.5%). Six serious adverse reactions were considered related to darbepoetin alfa (thromboembolic events, 1.0%).

CONCLUSIONS

With the limitation of a retrospective design, our results suggest that darbepoetin alfa is a well tolerated treatment that increases hemoglobin levels and reduces the need for transfusion in cancer patients receiving chemotherapy in clinical practice.

Recombinant human erythropoietin promotes the acquisition of a malignant phenotype in head and neck squamous cell carcinoma cell lines in vitro

Background

Recent studies indicate an increase in tumor progression and recurrence in head and neck squamous cell carcinomas (HNSCC) of cancer patients taking recombinant human erythropoietin (rhEpo) for anemia. This study was undertaken to investigate the potential role of rhEpo in invasion, proliferation, and cisplatin-induced cell death in HNSCC cell lines.

Methods

The following experiments were performed with two HNSCC cell lines, UMSCC-10B and UMSCC-22B. Presence of EpoR in both cell lines was determined by western blot and quantitative PCR. Colorimetric MTS assays and clonogenic assays were used to study the effect of rhEpo at pharmacologically relevant doses on cell proliferation. Matrigel invasion assays were performed in order to determine effects of exogenous rhEpo on invasive abilities. Clonogenic assays were also used to study potential cytoprotective effects of rhEpo against cisplatin. Immunoblotting was done to analyze the effect of rhEpo on Akt phosphorylation. Finally, MTS and TUNEL assays were performed to test our hypothesis that Akt activation by PI3K was involved in rhEpo-mediated cisplatin resistance.

Results

HNSCC cell lines were shown to express Epo receptor (EpoR). RhEpo increased invasion 1.8-fold in UMSCC-10B and 2.6-fold in UMSCC-22B compared to control. RhEpo at 10 U/ml increased cell proliferation by 41% and 53% in UMSCC-10B and UMSCC-22B, respectively, and colony formation by 1.5-fold and 1.8-fold. UMSCC-10B treated with cisplatin and exposed to rhEpo at 1 and 10 U/ml resulted in a 1.7-fold and 3.0-fold increase in colony number compared to control, respectively. UMSCC-22B treated with cisplatin and rhEpo at 1 or 10 U/ml resulted in ~2.5-fold increase in colony number. A TUNEL assay demonstrated a 30.5% and 76.5% increase in survival in UMSCC-10B and UMSCC-22B cells, respectively, in cisplatin and rhEpo-treated cells compared to cisplatin alone. MTS assay showed similar cytoprotective effects. Western blot revealed increased phosphorylation of Akt upon exposure of HNSCC cell lines to rhEpo. MTS assay and TUNEL analyses implicate Akt as a likely contributor to regulation of rhEpo-mediated cytoprotection.

Conclusions

The results demonstrate that, in HNSCC cells expressing functional EpoR, rhEpo promotes invasion, cell proliferation, and induces resistance to cisplatin, which may contribute to tumor progression.

Randomized trial comparing dose reduction and growth factor supplementation for management of hematological side effects in HIV/hepatitis C virus patients receiving pegylated-interferon and ribavirin

BACKGROUND

Pegylated-interferon (PEG-IFN) and ribavirin (RBV), current standard treatment for hepatitis C virus (HCV) infection, are frequently associated with neutropenia and anemia, leading to high treatment discontinuation rates in HIV/HCV-coinfected patients. Our objective was to compare the effectiveness of intervening with hematologic growth factors versus dose reductions of standard HCV therapy for the management of treatment-induced hematologic disorders.

METHODS

Ninety-two HIV/HCV-coinfected, therapy-naive subjects received PEG-IFN alfa-2b 1.5 μg·kg⁻¹·wk⁻¹ and RBV 13 ± 2 mg·kg⁻¹·d⁻¹ for up to 48 weeks. Before treatment initiation, subjects were randomized to subsequently receive growth factors, recombinant human erythropoietin (rHuEPO) and/or granulocyte colony-stimulating factor, or dose reduction (RBV and/or PEG-IFN) for anemia and neutropenia management, respectively. We analyzed the ability of each management strategy to control anemia and neutropenia and the percentage of subjects who achieved a successful treatment outcome according to the different management strategies.

RESULTS

During treatment, 43 subjects developed anemia (human erythropoietin, n = 24; dose reduction, n = 19), whereas 25 subjects developed neutropenia (granulocyte colony-stimulating factor, n = 10; dose reduction, n = 15). After the intervention, the increase in both hemoglobin and absolute neutrophil counts did not differ between the 2 side effect management strategies. Sustained response percentages were similar comparing anemic and neutropenic subjects regardless of management strategy (anemia: recombinant human erythropoietin, 29% versus dose reduction, 21%, P = 0.92; neutropenia: granulocyte colony-stimulating factor, 40% versus dose reduction, 20%, P = 0.46).

CONCLUSIONS

Growth factor supplementation and dose reduction do not seem to differ as management strategies for anemia and neutropenia in HIV/HCV-coinfected individuals treated with PEG-IFN/RBV.

Transfusion risk in cancer patients with chemotherapy-induced anemia when initiating darbepoetin alfa therapy at a baseline hemoglobin level of <9 g/dL versus 9 to <10 g/dL versus ≥ 10 g/dL: an exploratory analysis of a phase 3 trial

Darbepoetin alfa (DA) is an erythropoiesis-stimulating agent (ESA) approved for treating chemotherapy-induced anemia (CIA). Safety concerns have prompted changes to the ESA-product information, which now recommends initiating ESAs at hemoglobin (Hb) levels < 10 g/dL (US) or ≤ 10 g/dL (EU). The present exploratory analysis of a DA trial examined how baseline-Hb levels at ESA initiation affect transfusion rates, Hb response, and safety outcomes in CIA patients. Data were retrospectively analyzed from a phase 3 trial of CIA patients randomised to 500 mcg DA every 3 weeks (Q3 W) or to 2.25 mcg/kg DA weekly (QW) for 15 weeks. In the current analysis, data were reanalyzed by baseline-Hb categories of <9 g/dL (n = 126), 9 to <10 g/dL (n = 225), and ≥ 10 g/dL (n = 354). The Q3 W and QW groups were combined. Transfusion rates were highest in the <9 g/dL baseline-Hb group in all time periods examined. The Kaplan-Meier percentage (95% CI) of patients achieving Hb ≥ 10 g/dL was 68% (59, 78) and 88% (82, 92) in the <9 g/dL and 9 to <10 g/dL baseline-Hb groups, respectively. With lower baseline-Hb, incidence of a ≥ 1 g/dL-Hb rise in 14 days progressively decreased. Incidence of venous thromboembolic events was similar in all baseline-Hb groups and similar between patients with or without a ≥ 1 g/dL-Hb rise in 14 days. Overall, transfusion risk increased and Hb response decreased at lower baseline-Hb levels in this exploratory analysis. When following ESA-product information to initiate ESAs at Hb ≤ 10 g/dL, the greatest benefit may be achieved when initiating close to 10 g/dL. Prospective studies are needed to further examine this hypothesis.

Risk factors and incidence of thromboembolic events (TEEs) in older men and women with breast cancer

BACKGROUND

The purpose of this study is to evaluate the risk factors and the prevalence of thromboembolic events (TEEs) in breast cancer patients.

PATIENTS AND METHODS

This is a retrospective cohort study using the Surveillance, Epidemiology, and End Results-Medicare database. Breast cancer patients diagnosed from 1992 to 2005 ≥66 years old were identified. International Classification of Diseases, Ninth Revision, and Healthcare Common Procedure Coding System codes were used to identify TEEs within 1 year of the breast cancer diagnosis. Analyses were conducted using descriptive statistics and logistic regression.

RESULTS

A total of 89 841 patients were included, of them 2658 (2.96%) developed a TEE. In the multivariable analysis, males had higher risk of a TEE than women [odd ratio (OR) = 1.57; confidence interval (CI) 1.10-2.25] and blacks had higher risk than whites (OR = 1.20; CI 1.04-1.40). Compared with stage I patients, patients with stage II, III and IV had 22%, 39% and 98% increase, respectively, in risk. Placement of central catheters (OR = 2.71; CI 2.43-3.02), chemotherapy treatment (OR = 1.66; CI 1.48-1.86) or treatment with erythropoiesis-stimulating agents (ESAs) (OR = 1.33; CI 1.33-1.52) increase the risk. Other significant predictors included comorbidities, age, receptor status, marital status and year of diagnosis. Similar estimates were seen for pulmonary embolism, deep vein thromboembolism and other TEEs.

CONCLUSIONS

In total, 2.96% of patients in this cohort developed a TEE within 1 year from breast cancer diagnosis. Stage, gender, race, use of chemotherapy and ESAs, comorbidities, receptor status and catheter placement were associated with the development of TEEs.

Randomised, phase III trial of epoetin-β to treat chemotherapy-induced anaemia according to the EU regulation

BACKGROUND

Erythropoietin-stimulating agents (ESAs) effectively decrease the transfusion requirements of patients with chemotherapy-induced anaemia (CIA). Recent studies indicate that ESAs increase mortality and accelerate tumour progression. The studies also identify a 1.6-fold increased risk of venous thromboembolism. The ESA labelling was thus revised in Europe and the United States in 2008. This is the first randomised, phase III trial evaluating the efficacy and safety of epoetin-β (EPO), an ESA, dosed in accordance with the revised labelling, which specifies that ESAs should be administered to CIA patients with a haemoglobin level of ≤ 10 g dl⁻¹ and that a sustained haemoglobin level of > 12 g dl⁻¹ should be avoided.

METHODS

A total of 186 CIA patients (8.0 g dl⁻¹ ≤ haemoglobin ≤ 10.0 g dl⁻¹) with lung or gynaecological cancer were randomised to receive EPO 36,000 IU or placebo weekly for 12 weeks.

RESULTS

The proportion of patients receiving transfusions or with haemoglobin < 8.0 g dl⁻¹ between week 5 and the end of the treatment period as the primary end point was significantly lower in the EPO group (n=89) than in the placebo group (n=92; 10.0% vs 56.4%, P < 0.001). The proportion receiving transfusions was significantly lower in the EPO group (4.5% vs 19.6%, P=0.002). Changes in quality of life were not different. No significant differences in adverse events - for example, the incidence of thromboembolic events was 1.1% for each group - or the 1-year overall survival were observed between groups.

CONCLUSION

Weekly EPO administered according to the revised labelling approved by the European Medicines Agency is effective and well tolerated for CIA treatment. Further investigations are needed on the effect of ESAs on mortality.

Analysis of incidence and clinical outcomes in patients with thromboembolic events and invasive exocrine pancreatic cancer

BACKGROUND

Pancreatic adenocarcinoma is among the most common malignancies associated with thromboembolic events (TEs); however, reported incidence figures vary significantly and contain small patient cohorts. Pancreatic cancer-specific thrombosis studies examining the correlation between clinical variables, including thrombosis timing and the impact of thrombosis on survival, have not been reported.

METHODS

Survival analyses were performed relating to the development and timing of a TE in 1915 patients administered chemotherapy at Memorial Sloan-Kettering Cancer Center with invasive exocrine pancreatic cancer from January 1, 2000 to December 31, 2009. TE timing, relative to clinical parameters including laboratory data, erythropoietin-stimulating agent use, and body mass index (BMI), were also analyzed.

RESULTS

A thrombosis was identified in 690 (36%) patients. After adjusting for patients with pancreatic surgery and thrombosis (n = 127), developing a TE significantly increased the risk of death (hazard ratio [HR], 2.6; 95% confidence interval [CI], 2.3-2.8; P < .01). Patients with an early TE (within 1.5 months from pancreatic cancer diagnosis) had a significantly higher risk of death (HR, 2.1; 95% CI, 1.7-2.5; P < .01) compared with patients with late TE or no TE. Erythropoietin-stimulating agent use and an elevated international normalized ratio were associated with significantly shorter time to thrombosis. Low BMI was associated with significantly longer time to thrombosis.

CONCLUSIONS

TEs are common in exocrine pancreatic cancer, with coagulopathy, erythropoietin-stimulating agent use, and underweight BMI influencing thrombosis timing. TEs, particularly early ones, confer a significantly worse prognosis, suggesting a biological significance, underscoring the relevance of ongoing prophylaxis trials, and raising the question of whether early TEs should be considered a stratification factor for clinical trials.

Anti-vascular endothelial growth factor antibody bevacizumab reduced the risk of anemia associated with chemotherapy-A meta-analysis

INTRODUCTION

Vascular endothelial growth factor (VEGF) may play a role in erythropoiesis. We performed a meta-analysis of randomized controlled trials (RCT) to determine the effect of the anti-VEGF antibody bevacizumab on anemia in cancer patients treated with chemotherapy.

METHODS

Databases from PUBMED, the Web of Science, Embase, the Cochrane Library, and abstracts presented at the American Society of Clinical Oncology (ASCO) conferences until May 2010 were searched to identify relevant studies. Eligible studies included prospective RCTs in which the combination of bevacizumab and chemotherapy was compared with chemotherapy alone. Summary incidence rate, relative risk (RR), and 95% confidence interval (CI) were calculated.

RESULTS

A total of 6439 patients with a variety of solid tumors were included for analysis from 11 RCTs. Among those patients receiving bevacizumab and chemotherapy, the incidences of all-grade and high-grade (grade 3 and above) anemia were 17.8% (95% CI: 11.1-27.1%) and 2.8% (95% CI: 1.6-5.0%) respectively. In comparison with chemotherapy alone, bevacizumab significantly reduced all-grade (RR, 0.79; 95% CI: 0.66-1.0, p = 0.007) and high-grade anemia (RR, 0.72; 95% CI: 0.57-0.90, p = 0.005). The effect did not vary significantly among bevacizumab doses (p = 0.88), tumor types (p = 0.75) or chemotherapy regimens (p = 0.98).

DISCUSSION

Bevacizumab may significantly reduce the risk of anemia with chemotherapy in cancer patients.

Complications associated with erythropoietin-stimulating agents in patients with metastatic breast cancer: a Surveillance, Epidemiology, and End Results-Medicare study

BACKGROUND

The authors evaluated the patterns of use and the risk of thromboembolic events (TEE) associated with erythropoietin-stimulating agents (ESAs) in older patients with metastatic breast cancer who were receiving chemotherapy.

METHODS

The study was retrospective and used the SEER-Medicare linked database. Stage IV breast cancer patients diagnosed from 1995-2005, treated with chemotherapy, ≥66 years old, with full coverage of Medicare A and B were included. The World Health Organization's International Classification of Diseases (ICD-9) and the Healthcare Common Procedure Coding System (HCPCS) were used to identify the use of ESAs, chemotherapy, and complications of therapy. Analyses included descriptive statistics and logistic regression.

RESULTS

Of 2266 women, 980 (43.3%) received ESAs, and 1286 (56.7%) did not. Patients diagnosed after 1999 or who received treatment with taxanes, anthracyclines, or vinorelbine were more likely to receive ESAs. Patients receiving ESAs had higher rates of stroke (18.5% vs 15.1%, P = .031); deep-vein thrombosis (DVT; 21.3% vs 14.4%, P<.001), other/unspecified thromboembolic event (TEE; 19.8% vs 14.7%, P = .001), and any clot (31.3% vs 23.4%, P<.0001). In multivariate analysis, patients receiving ESAs had increased risk for DVT (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.05-1.75), and any clot (OR, 1.26; 95% CI, 1.02-1.57). A dose-dependent effect was evident for stroke, DVT, other TEE, and any clot.

CONCLUSIONS

In this cohort of patients, the use of ESAs increased the risk of TEEs, with a dose-dependent effect for stroke, DVT, other TEE, and any clot. The data show that among patients treated with chemotherapy and ESAs for metastatic breast cancer, TEEs are a common event. Therefore, caution is recommended when using these agents.

Incidence and risk of congestive heart failure in patients with renal and nonrenal cell carcinoma treated with sunitinib

PURPOSE

Sunitinib is a multitargeted receptor tyrosine kinase inhibitor approved for treatment of renal cell carcinoma (RCC) and GI stromal tumor. Congestive heart failure (CHF) is an important adverse effect that has been reported with sunitinib, but overall incidence and relative risk (RR) remain undefined. We performed an up-to-date meta-analysis to determine the risk of developing CHF in patients with both RCC and non-RCC tumors treated with sunitinib.

METHODS

Medline databases were searched for articles published between January 1966 and February 2011. Eligible studies were limited to phase II and III trials of sunitinib with adequate safety reporting in patients with cancer of any tumor type. Summary incidence, RR, and 95% CIs were calculated using random- or fixed-effects models based on the heterogeneity of included studies.

RESULTS

A total of 6,935 patients were included. Overall incidence for all- and high-grade CHF in sunitinib-treated patients was 4.1% (95% CI, 1.5% to 10.6%) and 1.5% (95% CI, 0.8% to 3.0%), respectively. RR of all- and high-grade CHF in sunitinib-treated patients compared with placebo-treated patients was 1.81 (95% CI, 1.30 to 2.50; P < .001) and 3.30 (95% CI, 1.29 to 8.45; P = .01), respectively. On subgroup analysis, there was no difference observed in CHF incidence for patients with RCC versus non-RCC or in trials with or without cardiac monitoring. No evidence of publication bias was observed.

CONCLUSION

Sunitinib use is associated with increased risk of CHF in patients with cancer.

The role of erythropoietin and erythropoiesis-stimulating agents in tumor progression

Over the past few decades, understanding of the physiologic function of erythropoietin (EPO) has evolved significantly. EPO binds to erythropoietin receptors (EPOR), initiating signaling that stimulates growth, inhibits apoptosis, and induces the differentiation of erythroid progenitors to increase red blood cell mass. EPO has additionally been shown to exert tissue-protective effects on multiple tissues, suggesting a pleiotropic mechanism of action. Erythropoiesis-stimulating agents (ESA) are used clinically for treating cancer-related anemia [chemotherapy-induced anemia (CIA)]. Recent clinical trials have reported increased adverse events and/or reduced survival in ESA-treated cancer patients receiving chemotherapy, potentially related to EPO-induced cancer progression. Signaling pathways downstream of EPO/EPOR have been shown to influence numerous cellular functions in both normal and tumor cells, including proliferation, apoptosis, and drug resistance. Some studies have reported effects on proliferation, reduced chemotherapy efficacy, reduction of apoptosis, and resistance to selective therapies on cancer cell lines, whereas others have shown null effects. In addition, newer targeted cancer therapies that are directed toward specific signaling pathways may be antagonized by ESAs. This molecular interplay between anticancer agents and potential survival signals triggered by ESAs may have been underestimated and may contribute toward decreased survival seen in certain trials. As more targeted anticancer therapies become available, these types of interactions may mitigate therapeutic efficacy by allowing tumor cells to acquire drug resistance. Therefore, a more complete understanding of the complex pathways involved will allow for the rational use of ESAs for the safe treatment of CIA in oncology patients.

Current targeted therapies in breast cancer: clinical applications in the elderly woman

The incidence of breast cancer is two to three times higher in women aged ≥65 years than in the whole population, whereas their mortality rate is threefold to fourfold higher. Targeted therapies allow significantly longer disease-free survival times. Nevertheless, in an elderly population, these treatments need to be prescribed with caution. This paper reviews the treatments of breast cancer in the elderly, and the issues of targeted therapies and their toxicities. Patients with human epidermal growth factor receptor (HER)-2(+) breast cancer benefit from trastuzumab; although cardiotoxic effects are observed in <5% of patients when given alone, they affect ~25% of patients when combined with anthracyclines. Bevacizumab leads to a longer progression-free survival time and lower risk for progression in patients with metastatic breast cancer when added to paclitaxel or docetaxel. Although generally well tolerated, it is associated with a higher risk for arterial thromboembolism and hypertension. Lapatinib is approved for the treatment of advanced or metastatic breast cancer in patients not responding to trastuzumab, combined with capecitabine chemotherapy. The most frequent side effects concern the gastrointestinal system and dermatologic symptoms. The life expectancy of breast cancer patients should be taken into account to determine the appropriateness of treatments. The quality of life of elderly cancer patients must be assessed with an appropriate tool. Older patients exhibit greater vulnerability, suggesting identification and exclusion of patients at high cardiac risk. Future recommendations for the treatment of elderly women with breast cancer should include a multidisciplinary approach and a global geriatric assessment before treatment with anti-HER-2 therapy or bevacizumab.

The prognostic impact of duration of anemia during chemotherapy in advanced epithelial ovarian cancer

OBJECTIVE

To propose a measure of anemia to be used as a prognostic factor for progression-free survival and overall survival in advanced epithelial ovarian cancer patients.

PATIENTS AND METHODS

Seventy-six patients with International Federation of Gynecology and Obstetrics stage III and stage IV epithelial ovarian cancer who had received at least six courses of platinum- and taxane-based systemic chemotherapy and achieved clinical or pathologic complete response were included. A novel prognostic factor based on the duration of anemia was proposed and the impact of anemia on progression-free and overall survival times was analyzed by a log-rank test and a Cox proportional hazards model.

RESULTS

We introduce a binary variable, Hb1020, that takes a value of 1 if the duration of a hemoglobin (Hb) level <10 g/dL is ≥20% of the total duration of chemotherapy. We propose Hb1020 as a potential prognostic factor for epithelial ovarian cancer. The 5-year progression-free survival rates were 48.4% in the Hb1020 = 0 group (duration of Hb <10 g/dL <20% of total duration) and 17.7% in the Hb1020 = 1 group (p = .026). The 5-year overall survival rates were 64.6% and 45.0%, respectively (p = .015).

CONCLUSIONS

Hb1020, based on the duration of anemia, is a potential prognostic factor for epithelial ovarian cancer. Using Hb1020, we will be able to administer highly optimized treatment for anemia to improve patient survival. Further independent studies are needed to confirm its prognostic role.

Treatment of anemia with darbepoetin alfa in heart failure

Anemia is common in heart failure (HF) patients. A prespecified pooled analysis of 2 randomized, double-blind, placebo-controlled studies evaluated darbepoetin alfa (DA) in 475 anemic patients with HF (hemoglobin [Hb], 9.0-12.5 g/dL). DA was administered subcutaneously every 2 weeks and titrated to achieve and maintain a target Hb level of 14.0+/-1.0 g/dL. By week 27, mean (SD) Hb concentrations did not increase with placebo but increased with DA from 11.5 (0.7) to 13.3 (1.3) g/dL. Hazard ratios (HRs) for DA compared with placebo for all-cause death or first HF hospitalization (composite end point), all-cause death, and HF hospitalization by month 12 were 0.67 (95% confidence interval [CI], 0.44-1.03; P=.067), 0.76 (95% CI, 0.39-1.48; P=.419), and 0.66 (95% CI, 0.40-1.07; P=.093), respectively. Incidence of adverse events was similar in both groups. In post hoc analyses, improvement in the composite end point was significantly associated with the mean Hb change from baseline (adjusted HR, 0.40; P=.017) with DA treatment. There was no increased risk of all-cause mortality or first HF hospitalization with DA in patients with reduced renal function or elevated baseline B-type natriuretic peptide, a biomarker of worse HF. These results suggest that DA is well tolerated, corrects HF-associated anemia, and may have favorable effects on clinical outcomes.

Erythropoiesis-stimulating agents for anemic patients with cancer

Anemia in cancer patients is common and often associated with decreased survival and quality-of-life scores. The introduction of erythropoiesis-stimulating agents (ESAs) for the treatment of anemia in patients with solid tumors and nonmyeloid malignancies in the 1990s has proved an important alternative to red blood cell transfusions. ESAs have been consistently shown to increase hemoglobin levels and reduce transfusion requirements in anemic cancer patients whilst also being associated with improvements in quality of life. Several recent studies, however, have raised concerns about the safety of ESAs with regards to an increased number of thrombo-embolic events, decreased on-study survival and possible effects of ESAs on tumor progression. This has led to a reappraisal of the role of ESAs in the treatment of anemic cancer patients. It remains generally accepted that, if used within current guidelines and labeling recommendations, ESAs can still be considered safe in patients receiving chemotherapy once individual risks are balanced against possible benefits.