Prognostic importance of anemia related parameters in patients with carcinoma of the cervix uteri

Hemoglobin variation and blood transfusion rates in patients affected by locally advanced cervical cancer undergoing neo-adjuvant chemotherapy followed by radical surgery: the role of erythropoietic growth factors

BACKGROUND

The objectives of the present study were to evaluate hemoglobin levels and consequent clinical behaviors related to anemia developed in patients affected by locally advanced cervical cancer treated with neo-adjuvant chemotherapy in the last decade and to evaluate the impact that the introduction of erythropoietic growth factors had in the clinical practice.

PATIENTS AND METHODS

Blood chemistries, prospectively recorded from 98 cervical cancer patients, treated with neo-adjuvant chemotherapy and, if necessary, erythropoietic growth factors, were compared with matched historical controls before the introduction of growth factors in clinical practice.

RESULTS

Hemoglobin level in the study group did not differ significantly during chemotherapy. At the third cycle of chemotherapy and at the end of chemotherapy, hemoglobin level was significantly higher in the study group compared with the control group. Transfusion rates in the study group were significantly lower. The analysis within the study group revealed that hemoglobin level in patients who suffer at diagnosis from anemia tends to increase whereas hemoglobin level in nonanemic patients tends to decrease.

CONCLUSIONS

Erythropoietic growth factors increase hemoglobin level and reduce blood transfusions in cervical cancer patients undergoing neo-adjuvant chemotherapy followed by radical surgery. An appropriate autologous blood donation program can noticeably reduce homologous blood transfusions.

Hypoxia and anemia: factors in decreased sensitivity to radiation therapy and chemotherapy?

Hypoxia is a common feature of solid tumors that occurs across a wide variety of malignancies. Hypoxia and anemia (which contributes to tumor hypoxia) can lead to ionizing radiation and chemotherapy resistance by depriving tumor cells of the oxygen essential for the cytotoxic activities of these agents. Hypoxia may also reduce tumor sensitivity to radiation therapy and chemotherapy through one or more indirect mechanisms that include proteomic and genomic changes. These effects, in turn, can lead to increased invasiveness and metastatic potential, loss of apoptosis, and chaotic angiogenesis, thereby further increasing treatment resistance. Investigations of the prognostic significance of pretreatment tumor oxygenation status have shown that hypoxia (oxygen tension [pO(2)] value < or =10 mmHg) is associated with lower overall and disease-free survival, greater recurrence, and less locoregional control in head and neck carcinoma, cervical carcinoma, and soft-tissue sarcoma. In view of the deleterious effect of hypoxia on standard cancer treatment, a variety of hypoxia- and anemia-targeted therapies have been studied in an effort to improve therapeutic effectiveness and patient outcomes. Early evidence from experimental and clinical studies suggests the administration of recombinant human erythropoietin (rHuEPO) may enhance the effectiveness of radiation therapy and chemotherapy by increasing hemoglobin levels and ameliorating anemia in patients with disease- or treatment-related anemia. However, further research is needed in the area of hypoxia-related treatment resistance and its reversal.

Prevalence and outcomes of anemia in cancer: a systematic review of the literature

Anemia is common in patients with cancer. This systematic literature review of reports published in 1966 through February 2003 identified the prevalence of anemia in specific cancers and assessed the impact of anemia on survival and quality of life (QOL). Studies about chemotherapy-induced anemia were excluded. Anemia prevalence varied widely; most studies found that between 30% and 90% of patients with cancer had anemia. Prevalence was affected strongly by the definition of anemia: 7% of patients with Hodgkin disease had anemia when the condition was defined as a hemoglobin level <90.0 g/L; as many as 86% of patients had anemia when it was defined as a hemoglobin value <110.0 g/L. Prevalence varied by cancer type and disease stage: 40% of patients with early-stage colon tumors and nearly 80% of patients with advanced disease had anemia. Patients with anemia had poorer survival and local tumor control than did their nonanemic counterparts in 15 of 18 studies. In 8 of 12 studies, patients without anemia (most treated with epoetin) needed fewer transfusions. QOL was positively correlated with hemoglobin levels in 15 of 16 studies. There was no significant difference in treatment toxicity between patients with and without anemia. Tumor hypoxia, which has been associated with resistance to radiation therapy and chemotherapy, may stimulate angiogenesis, leading to poor local control of tumors and increased morbidity and mortality. Treatment of anemia may have a significant impact on patient survival and QOL. However, a standard definition of anemia is needed, as is research about the effect of anemia on cancer progression.

Impact of tumor hypoxia and anemia on radiation therapy outcomes

Local recurrence remains a major obstacle to achieving cure of many locally advanced solid tumors treated with definitive radiation therapy. The microenvironment of solid tumors is hypoxic compared with normal tissue, and this hypoxia is associated with decreased radiosensitivity. Recent preclinical data also suggest that intratumoral hypoxia, particularly in conjunction with an acid microenvironment, may be directly or indirectly mutagenic. Investigations of the prognostic significance of the pretreatment oxygenation status of tumors in patients with head and neck or cervical cancer have demonstrated that increased hypoxia, typically designated in these studies as pO(2) levels below 2.5-10 mm Hg, is associated with decreased local tumor control and lower rates of disease-free and overall survival. Hypoxia-directed therapies in the radiation oncology setting include treatment using hyperbaric oxygen, fluosol infusion, carbogen breathing, and electron-affinic and hypoxic-cell sensitizers. These interventions have shown the potential to increase the effectiveness of curative-intent radiation therapy, demonstrating that the strategy of overcoming hypoxia may be a viable and important approach. Anemia is common in the cancer population and is suspected to contribute to intratumoral hypoxia. A review of the literature reveals that a low hemoglobin level before or during radiation therapy is an important risk factor for poor locoregional disease control and survival, implying that a strong correlation could exist between anemia and hypoxia (ultimately predicting for a poor outcome). While having a low hemoglobin level has been shown to be detrimental, it is unclear as to exactly what the threshold for "low" should be (studies in this area have used thresholds ranging from 9-14.5 g/dl). Optimal hemoglobin and pO(2) thresholds for improving outcomes may vary across and within tumor types, and this is an area that clearly requires further evaluation. Nonetheless, the correction of anemia may be a worthwhile strategy for radiation oncologists to improve local control and survival.