Hemoglobin levels and acute radiotherapy-induced toxicity

To analyze the possible correlation between hemoglobin concentration and the appearance of acute radiotherapy-induced toxicity. We prospectively studied hemoglobin levels and acute radiotherapy-induced toxicity in 86 patients treated for 3 months. Both sexes were considered to have anemia if their hemoglobin level was < or = 12 g/dL. No patient received corrective treatment for hemoglobin levels. Acute toxicity was analyzed weekly during radiotherapy and 45 days after therapy ended. The possible relationship between anemia and toxicity was analyzed, as was the correlation between hemoglobin values and the degree of toxicity. The findings were similar for all prognostic factors in patients with and without anemia. Hemoglobin concentration was < or = 12 g/dL in 24 patients (27.9%; mean, 10.93 +/- 0.78 g/dL). At the end of radiotherapy, hemoglobin levels were < or = 12 g/dL in 18 patients (20.9%; mean, 11.26 +/- 1.06 g/dL). The correlation between pretherapy and posttherapy hemoglobin concentration was significant at r = 0.729 (P = 0.01). The correlation between absolute hemoglobin values and the degree of toxicity, and the possible relationship between hemoglobin concentration and the appearance or the degree of toxicity after radiotherapy, was not significant. The relationship between hemoglobin concentration and oxygenation of the tumor and healthy tissues was not linear. This may account for the influence of hemoglobin levels on control of the disease as reported in earlier studies, but it does not account for their influence on acute toxicity after radiotherapy.