Is there an optimal hemoglobin level for patients with glioblastoma multiforme?

The purpose of this study was to assess the relationship between hemoglobin levels and survival for patients treated with radiation therapy for glioblastoma multiforme.

Between 1992 and 2001, 89 patients with newly diagnosed glioblastoma multiforme were treated with a minimum of 50 Gy of radiation therapy. The primary study endpoint was overall survival. The independent variables analyzed included peak hemoglobin level, age, sex, extent of surgery, and duration of therapy. The peak hemoglobin level was the highest hemoglobin value obtained within 1 week before the initiation of radiation therapy or at some point during radiation therapy. The peak hemoglobinlevel was stratified into values of less than or equal and values greater than for each of the following hemoglobin values: 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, and 14.0 g/dL.

On univariate analysis, age (< or = 50 years of age) and surgical treatment (resection) were significant for increased survival at 1 year. When univariate analysis was performed on the stratification of the peak hemoglobin, levels greater than 11.0, 13.5, and 14.0 g/dL reached statistical significance for increased survival. Multivariate analysis was then performed on models composed of the hemoglobin levels that reached significance, and the other independent variables were investigated. In all models, both age and the peak hemoglobin level tested were prognostic for survival. However, for the hemoglobin level of 11.0 g/dL, an interaction was detected between hemoglobin and age.

We found that increasing hemoglobin levels may have prognostic implications and could thus influence clinical outcome. We will be seeking to verify our results in larger cohorts.