According to results presented at the 17th International Symposium of the Multinational Association of Supportive Care in Cancer and the International Society for Oral Oncology (MASCC-ISOO), patients with lower hemoglobin levels at the start of chemotherapy have a worse prognosis than patients with normal levels of hemoglobin.
Anemia is a condition where circulating red blood cells (RBCs) fall below normal levels. Red blood cells are responsible for delivering oxygen to tissues throughout the entire body. Bone marrow (spongy material inside large bones) is stimulated to produce RBCs by a chemical substance called erythropoietin, which is secreted by the kidneys. Each RBC contains many molecules of hemoglobin, a protein-iron complex responsible for delivering oxygen to the cells and carbon dioxide to the lungs.
Common symptoms of anemia include severe fatigue, shortness of breath, greatly diminished activity levels and a reduced overall feeling of well-being. Severe anemia often requires blood transfusions, which have associated risks of infection, rejection and increased medical costs. Furthermore, severe anemia may diminish chances of a cure or optimal long-term survival when its side effects cause a delay in the dose of cancer treatment. Anemia may be caused by treatment for cancer or by the disease itself.
Erythropoietin can be manufactured outside the body and administered to patients. Recombinant human erythropoietin, or epoetin alfa, is comprised of manufactured erythropoietin and is commonly used for cancer patients receiving treatment. Epoetin alfa has been shown to reduce the severity of anemia and reduce symptoms of fatigue by stimulating the bone marrow to produce more RBCs. The two forms of epoetin alfa most often utilized for the treatment of anemia in the United States are Aranesp® (darbepoetin alfa) and Procrit® (epoetin alfa). Aranesp, which requires less frequent dosing than Procrit, has been approved by the FDA for the treatment of anemia caused by chemotherapy in non-myeloid cancers (cancers that do not originate in blood cells). Less frequent dosing means fewer injections and fewer office visits, so patients and caregivers have fewer interruptions from their daily lives. Furthermore, caregivers may spend less time scheduling appointments and treating anemia and focus on other patient needs. The use of Aranesp is gaining momentum in the clinical setting as results from clinical trials continue to indicate its effectiveness in comparison to Procrit. Researchers have also been evaluating whether anemia has any relation to differences in outcomes among patients with various types of cancer.
Researchers from France recently evaluated data from two previously conducted, large clinical trials to evaluate the effects of low levels of hemoglobin (anemia) prior to therapy in patients with advanced non-small cell lung cancer (NSCLC). The data included 422 patients with either stage IIIB or stage IV NSCLC who were treated with chemotherapy consisting of the agents Gemzar® (gemcitabine) and Platinol® (cisplatin). Overall, patient and disease characteristics were similar between all the groups of patients. Researchers found no differences in survival when comparing stages of cancer, age or gender of patients. However, they did determine that duration of overall survival was associated with hemoglobin levels prior to chemotherapy. Patients who had a lower hemoglobin levels had lower survival rates than patients with higher hemoglobin levels-overall, patients with a hemoglobin level of 12.0g/dL or higher had an average survival of 12.3 months, compared to only 8.8 months for patients whose hemoglobin levels were less than 12.0 g/dL. Furthermore, patients with hemoglobin levels of 10.5 g/dL or higher survived an average of 13.4 months, compared to only 10 months for those patients whose hemoglobin was 10.0 g/dL or lower. Performance status (the ability to perform daily activities) was also associated with duration of survival: Patients whose performance status scores were the lowest (greatest ability to perform daily activities) had an average survival of 12.2 months, while those whose performance status scores were the highest (least ability to perform daily activities) had an average survival of less than half that duration at only 5.9 months.
The researchers concluded that higher hemoglobin levels prior to therapy are associated with longer overall survival in patients with advanced NSCLC who are to be treated with Gemzar- and Platinol-based chemotherapy. Future trials are necessary to determine if treatment with agents such as Aranesp to improve hemoglobin levels prior to therapy in patients with low initial levels can change outcomes. Patients with NSCLC who are to be treated with chemotherapy may wish to speak with their physician regarding their individual risks and benefits of treatment with Aranesp.
Reference: Juan O, et al. Impact of Hemoglobin Level on the Outcome of Advanced Non-Small-Cell Lung Cancer (NSCLC) Treated with Cisplatin and Gemcitabine. Proceedings from the 17th International Symposium of the Multinational Association of Supportive Care in Cancer and the International Society for Oral Oncology (MASCC-ISOO). Barcelona, Spain. July 2005. Abstract 02-008.