• 3/21/2005
  • www.cancerconsultants.com

Researchers from Duke University have reported that anemic patients with advanced head and neck cancers treated with radiation therapy have poorer outcomes than comparable patients without anemia. The details of this retrospective analysis were reported in the March 15, 2005 issue of the International Journal of Radiation Oncology Biology Physics.[1]

Hypoxia is known to interfere with the therapeutic effectiveness of radiation therapy and chemotherapy. It has been suggested that clinical anemia can reduce responses to radiation therapy and chemotherapy. In the current study, researchers evaluated outcomes of 159 patients with head and neck cancer treated with a standardized radiation and chemotherapy regimen. Radiation was hyperfractionated and the chemotherapy drug was cisplatin. This group of patients had a median hemoglobin of 13.6 g/dL. The researchers compared outcomes of patients who had hemoglobin levels of 13.0 g/dL with those who had levels below 13.0 g/dL. The five-year failure-free survival was 75% for patients with a hemoglobin of 13.0 g/dL or higher, compared to 50% for those with a lower hemoglobin level. However, patients with anemia appeared to have on average more extensive disease at the time of treatment. These authors concluded that anemia was associated with a worse outcome, but that the cause was unknown. They proposed prospective trials of erythropoietin (Procrit® or Aranesp®) to determine if correction of anemia improves outcome.

Comments: Preliminary results from a Radiation Therapy Oncology Group (RTOG) study indicated that erythropoietin improved hemoglobin levels in anemic patients with head and neck cancers receiving only radiation therapy, but did not improve survival, cancer-free survival, or control of cancer. This study was closed early when an unplanned interim analysis revealed that it would be extremely unlikely (<5% chance) that erythropoietin would improve cancer-control or survival. These results were reported in the plenary session of the 46th annual meeting of the American Society of Therapeutic Radiology and Oncology (ASTRO) held in Atlanta, GA, Oct 3-7, 2004.[2] More studies are clearly needed to answer the question of whether or not correcting anemia will improve outcomes. There are no reported randomized trials of anemia correction in patients with head and neck cancer receiving both chemotherapy and radiation therapy.

References:
[1] Pretreatment anemia is correlated with the reduced effectiveness of radiation and concurrent chemotherapy in advanced head and neck cancer. International Journal of Radiation Oncology Biology Physics. 2005;61:1087-1095.
[2] Machtay M, Pajak T, Suntharalingam M, et al. Definitive Radiotherapy Erythropoietin for Squamous Cell Carcinoma of the Head and Neck: Preliminary Report of RTOG 99-03. Proceedings from the 46th annual meeting of the American Society for Therapeutic Radiology and Oncology, Atlanta GA, Oct 2-5 2004, Abstract #5.