Blood Transfusion in Patients Receiving Radical Radiotherapy: A Reappraisal

Abstract

Blood transfusion has been widely touted as a useful adjunct to radiation therapy. This is based on the premise that higher hemoglobin levels will increase tissue oxygenation thereby improving the efficacy of therapeutic radiation. Consequently, it has become common clinical practice to transfuse patients undergoing radiotherapy to arbitrary hemoglobin levels. There has been extensive research evaluating the use of transfusion with radiotherapy. Animal data are divided regarding the radiobiologic benefits of transfusion. Clinical experience has established that anemia is a poor prognostic indicator in patients receiving radiotherapy. However, clinical trials have not clearly shown that correction of anemia by transfusion improves the outcomes. This may be explained by adverse effects of transfusion on tumor immunobiology. In addition to the well-known risks of infectious disease, alloimmunization, and allergic reactions, homologous blood has been shown to be immunosuppressive. This immunosuppression has been associated with decreased survival as well as increased rates of recurrence in the treatment of a variety of malignancies, thus making homologous transfusion particularly hazardous for the tumor-bearing patient. This suggests that routine use of transfusion to support patients receiving radiotherapy must be reappraised, and alternative methods of increasing hemoglobin, such as recombinant human erythropoietin (r-HuEPO), need to be considered. r-HuEPO represents a unique opportunity to assess the value of increasing hemoglobin mass without the confounding variable of immunosuppression. Consequently, a prospective clinical trial utilizing r-HuEPO in patients undergoing radiotherapy seems warranted.

Effect of subcutaneous recombinant human erythropoetin in cancer patients receiving radiotherapy: final report of a randomized, open-labelled, phase II trial

“…Because it is an axiom in radiobiology that hypoxic cells are less radioresponsive than aerated cells (Gray et al, 1953;Palcic and Skarsgard, 1984), it has been standard treatment to transfuse anaemic cancer patients to some arbitrary haemoglobin level in an effort to improve tissue oxygenation as well as to enhance patient comfort (Poskitt, 1987). Despite this practice, the routine use of blood transfusion to improve serum haemoglobin level has risks, including viral infection (HIV and hepatitis) and transfusion reaction (Bove, 1987;Poskitt, 1987;Levine and Vijayakumar, 1993). In addition, there is the potential down-regulation of host cellular immune function with transfusion (Blumberg and Heal, 1990).…”

“…A number of retrospective reviews have documented adverse outcomes (inferior overall and disease-free survival) in patients receiving blood transfusions for a variety of malignancies including colon/rectum, lung, prostate, uterine cervix, breast and soft tissues (Rosenberg et al, 1985;Tartter et al, 1985;Arnoux et al, 1988;Blumberg et al, 1988;Corman et al, 1988;Heal et al, 1988;Moores et al, 1989;Wobbes et al, 1989;Little et al, 1990;McClinton et al, 1990;Casper et al, 1991). Thus, although transfusion can improve tissue oxygenation and potentially enhance the effectiveness of RT, any radiobiological gain might be mitigated by the adverse effects of transfusion on tumour immunosurveillance (Levine and Vijayakumar, 1993). Recombinant erythropoetin offers the possibility of correcting cancer-related anaemia without subjecting patients to the risks of transfusion.…”

Enhanced radiosensitivity in experimental tumours following erythropoietin treatment of chemotherapy-induced anaemia

“…Anaemia is a common phenomenon in clinical oncology which can be caused by the neoplastic disorder itself [due to, for example, deficiency of erythropoietic factors, bone marrow inhibition by inflammatory cytokines, haemolysis, bone marrow infiltration or paraneoplastic syndromes (for a review see Levine et al, 1993;Spivak, 1994)], by myelosuppressive therapy modalities or by acute or chronic bleeding of the tumour. The anaemia can severely affect the general well-being of the patient and may limit the applicability and efficacy of several anti-tumour therapy modalities.…”

“…The anaemia can severely affect the general well-being of the patient and may limit the applicability and efficacy of several anti-tumour therapy modalities. Numerous studies have shown a strong relationship between the therapeutic outcome of radiotherapy and haemoglobin concentrations, indicating that anaemic patients have a poorer prognosis following standard radiotherapy [for reviews see (Grau et al, 1998;Levine et al, 1993)]. …”

“…With this in mind, several studies have investigated the effect of correcting anaemia by homologous blood or red blood cell (RBC) Received 2 December 1997Revised 16 February 1998Accepted 27 February 1998 Correspondence to: 0 Thews, Institute of Physiology and Pathophysiology, University of Mainz, Duesbergweg 6, D-55099 Mainz, Germany transfusion on tumour oxygenation (Kelleher et al, 1995) and the outcome of radiotherapy (Levine et al, 1993;Grau et al, 1998).…”