Hematopoietic Recovery using Multi-Cytokine Therapy in 8 Patients Presenting Radiation-Induced Myelosuppression after Radiological Accidents
Résumé
Treatment of accidental radiation-induced myelosuppression
is primarily based on supportive care and requires
specific treatment based on hematopoietic growth factors
injection or hematopoietic cell transplantation for the most
severe cases. The cytokines used consisted of pegylated
erythropoietin (darbepoetin alfa) 500 IU once per week,
pegylated G-CSF (pegfilgrastim) 6 mg 3 2 once, stem cell
factor 20 lg.kg–1 for five days, and romiplostim (TPO analog)
10 lg.kg1 once per week, with different combinations
depending on the accidents. As the stem cell factor did not
have regulatory approval for clinical use in France, the
French regulatory authorities (ANSM, formerly, AFSSAPS)
approved their compassionate use as an investigational drug
‘‘on a case-by-case basis’’. According to the evolution and
clinical characteristics, each patient’s treatment was adopted
on an individual basis. Daily blood count allows initiating GCSF
and SCF delivery when granulocyte ,1,000/mm3, TPO
delivery when platelets ,50,000/mm3, and EPO when Hb,80
g/L. The length of each treatment was based on blood cell
recovery criteria. The concept of ‘‘stimulation strategy’’ is
linked to each patient’s residual hematopoiesis, which varies
among them, depending on the radiation exposure’s characteristics
and heterogeneity. This paper reports the medical
management of 8 overexposed patients to ionizing radiation.
The recovery of bone marrow function after myelosuppression
was accelerated using growth factors, optimized by
multiple-line combinations. Particularly in the event of
prolonged exposure to ionizing radiation in dose ranges inducing severe myelosuppression (in the order of 5 to 8 Gy),
with no indication of hematopoietic stem cell transplantation.