Comparison of two strategies for the treatment of radiogenic leukopenia using granulocyte colony stimulating factor.

PURPOSE: Radiation-induced leukopenia can cause a delay or discontinuation of radiotherapy. This complication can be overcome with the use of granulocyte colony-stimulating factor (G-CSF). However, an uncertainty exists regarding the mode of application of G-CSF in patients treated with radiotherapy. For this reason, the efficacy of two strategies for the administration of G-CSF in irradiated patients was compared in a prospective randomized clinical study. METHODS AND MATERIALS: Forty-one patients who developed leukopenia (< 2.5 x 10(9) per liter) while undergoing radiotherapy were treated with G-CSF at a daily dose of 5 microg/kg. The first group received single injections of G-CSF as required (n = 21). The second group received G-CSF on at least 3 consecutive days (n = 20). An analysis was made of the changes in leukocyte counts, the number of days on which radiotherapy had to be interrupted, and the side effects of growth-factor treatment.
RESULTS: An increase in leukocyte values in the peripheral blood was observed in all patients treated with G-CSF. In the group which received G-CSF when required, two injections (range: 1-8) were administered in most cases. In the second group, most of the patients received three injections (range: 3-9). The average duration of therapy interruptions due to leukopenia was 4.8 days (0-28) in the first therapy arm and 2.5 (0-20) in the second arm. The variance in the duration of therapy interruptions between the two groups was not significant (p = 0.2). Radiotherapy had to be terminated in two patients due to thrombocytopenia but the application of G-CSF did not seem to be a reason of decreasing platelet counts.
CONCLUSIONS: Our results reveal that G-CSF is safe and effective in the treatment of radiation-induced leukopenia regardless of the mode of application. Because the calculated difference related to radiation treatment interruptions has no clinical relevance, both approaches examined in our study appear reasonable.

RCT Entities:   Population Interventions Outcomes