Use of recombinant granulocyte colony-stimulating factor in Fanconi's anemia

Granulocyte colony-stimulating factor (G-CSF) has been shown to improve the neutropenic status of patients with bone marrow failure. The side effects in prolonged treatment still need to be determined.

We have studied the efficacy and the long-term side effects of G-CSF in four patients with Fanconi's anemia and severe neutropenia.

Three patients responded with an increase in their absolute neutrophil count; neither improvement in platelet count and hemoglobin concentration nor effect on transfusion requirements was seen. CFU-GM and BFU-E were undetectable before, during and after treatment. Responders showed an important reduction in number and severity of infections, with a marked improvement of clinical status. The fourth patient developed acute myeloid leukemia after 4 weeks of G-CSF treatment. During maintenance, one patient was treated with G-CSF for 18 months, until she received bone marrow transplantation, without presenting side effects. In the second responding patient G-CSF treatment was stopped because of appearance of immature cells in peripheral blood and myeloid blasts in bone marrow. The third responding patient presented immature peripheral myeloid cells during the third year of G-CSF treatment: disappearance of immature cells was observed after G-CSF reduction. In two cases FISH analysis revealed monosomy 7 after G-CSF treatment.

G-CSF use results in an improvement of clinical status, but long term administration may cause adverse experiences and requires a close hematological monitoring.