Erythropoietin therapy and cancer related anaemia: updated Swedish recommendations

Role of Erythropoietin in Cerebral Glioma: An Innovative Target in Neuro-Oncology

BACKGROUND

Erythropoietin (EPO) is a cytokine primarily involved in the regulation of erythropoiesis. In response to hypoxia-ischemia, hypoxia-inducible factor 1 induces EPO production, which, in turn, inhibits apoptosis of erythroid progenitor cells. By the same mechanism and acting through other signaling pathways, EPO exerts neuroprotective effects. Increased resistance to hypoxia and decreased apoptosis are thought to be important mechanisms for tumor progression, including malignant glioma. Because recent studies have demonstrated that EPO and its receptor (EPOR) are expressed in several tumors and can promote tumor growth, in the present study, we investigated EPO and EPOR expression in human glioma and the effect of EPO administration in a rat model of glioma implantation.

METHODS

Using Western blotting and immunohistochemical analysis, we examined the expression of EPO, EPOR, platelet endothelial cell adhesion molecule, and Ki-67 in human glioma specimens and experimentally induced glioma in rats. In the experimental setting, a daily dose of recombinant human EPO (rHuEPO) or saline solution were administered for 21 days in Fischer rats subjected to 9L cell line implantation.

RESULTS

In both human and animal specimens, we found an increase in EPOR expression as long as the lesion presented with an increasing malignant pattern. A significant direct correlation was found between the expression of EPOR and Ki-67 and EPOR and platelet endothelial cell adhesion molecule in low- and high-grade gliomas. The rats treated with rHuEPO presented with significantly larger tumor spread compared with the saline-treated rats.

CONCLUSIONS

The results of our study have shown that the EPO/EPOR complex might play a significant role in the aggressive behavior of high-grade gliomas. The larger tumor spread in rHuEPO-treated rats suggests a feasible role for EPO in the aggressiveness and progression of malignant glioma.

Erythropoietin for cancer-associated malignant anemia: A meta-analysis

The present study aimed to evaluate the effectiveness of erythropoietin (EPO) for improving cancer-associated malignant anemia. A search was performed for randomized clinical trials, conducted according to the Cochrane manual, using electronic databases including PubMed, EMBASE, the Cochrane Library and ClinicalTrails.gov up to 15 August 2015. A total of 6 eligible studies from 5 articles enrolling a total of 453 patients were entered into the current meta-analysis. Upon EPO treatment, there were significant differences in the change in hemoglobin (HB) levels compared with the placebo at short-term follow-up [mean difference (MD)=0.66; 95% confidence interval (CI), 0.14-1.18; I2=Not applicable; P=0.01) and long-term follow-up (MD=0.10; 95% CI, 0.02-0.18; I2=Not applicable; P=0.01) under the random effects model. For changes in hematocrit (HCT) compared with the placebo, the results revealed there were significant differences at short-term follow-up (MD=2.47; 95% CI, 0.75-4.19; I2=Not applicable; P=0.005) and long-term follow-up (MD=7.60; 95% CI, 6.15-9.05; I2=Not applicable; P<0.00001) under the random effects model. Compared with the placebo in short-term follow-up under the fixed effects model with homogeneity, the result was a significant difference for the transfusion ratio [relative risk (RR)=0.81; 95% CI, 0.67- 0.97; I2=34%; P=0.02) and the transfusion requirements (MD=-0.45; 95% CI, -0.92, 0.03; I2=6%; P=0.07). Funnel plots did not detect any publication bias. These results suggest that EPO was beneficial to alleviate cancer-associated anemia and improve survival outcomes for patients with cancer.

Targeting the erythropoietin receptor on glioma cells reduces tumour growth

Hypoxia has been shown to be one of the major events involved in EPO expression. Accordingly, EPO might be expressed by cerebral neoplastic cells, especially in glioblastoma, known to be highly hypoxic tumours. The expression of EPOR has been described in glioma cells. However, data from the literature remain descriptive and controversial. On the basis of an endogenous source of EPO in the brain, we have focused on a potential role of EPOR in brain tumour growth. In the present study, with complementary approaches to target EPO/EPOR signalling, we demonstrate the presence of a functional EPO/EPOR system on glioma cells leading to the activation of the ERK pathway. This EPO/EPOR system is involved in glioma cell proliferation in vitro. In vivo, we show that the down-regulation of EPOR expression on glioma cells reduces tumour growth and enhances animal survival. Our results support the hypothesis that EPOR signalling in tumour cells is involved in the control of glioma growth.

The cost-effectiveness of treatment with erythropoietin compared to red blood cell transfusions for patients with chemotherapy induced anaemia: a Markov model

BACKGROUND

Anaemia is a common complication of chemotherapy. As anaemia can lead to e.g. fatigue, depression, social isolation and chest pain it diminishes physical capacity and quality of life. It is generally accepted that symptomatic anaemia should be corrected. Treatment options include red blood cell transfusion (RBCT), erythropoietin (EPO) administration or a combination of both.

OBJECTIVE

The objective of this study was to carry out a cost-effectiveness analysis of treatment with EPO (epoetin alfa), compared to treatment with RBCT for patients with chemotherapy-induced anaemia in Sweden from a health care perspective.

METHOD

A model was developed for estimating incremental costs and QALY gains associated with EPO treatment compared to treatment with RBCTs, based on a model commissioned by the UK National Institute for Health and Clinical Excellence and adjusted to reflect Swedish treatment practice. Data regarding patient characteristics, response rates, and RBCT was derived from a Swedish observational study of EPO treatment in cancer patients with chemotherapy related anaemia. Swedish guidelines and unit costs were used throughout the study. A systematic review of EPO for treatment of anaemia associated with cancer was used to estimate QALY gains associated with changes in Hb-concentrations in our model.

RESULTS

The model's results validate well to real world data from three major hospitals in Sweden. The cost per QALY gained from administration of EPO was estimated at EUR 24,700 in the base case analysis. Practicing an EPO treatment target Hb-level of 12 g/dl yields a cost per QALY about 40% lower than practicing a Hb-target level of 13 g/dl, which is in agreement with updated recommendations of using a 12 g/dl target.

CONCLUSION

The estimated cost per QALY falls well within the range acceptable in Sweden when practicing a Hb-target level of 12 g/dl. The incremental cost of elevating Hb-levels above 13 g/dl is very high in relation to the incremental QALY gain achieved.