We tried to treat 13 patients with
myelodysplastic syndromes (MDS),
leukemias and
myeloproliferative disorders, with
alfacalcidol for their hematological improvement. Eight of them had MDS, 2 acute
leukemia (M3, M4), 1
chronic myelogenous leukemia and 2
primary myelofibrosis. All patients were untreated except for 3 patients (PASA,
RAEB, AML-M4) who had been treated with
mepitiostane,
prednisolone and BH.AC-
AMP regimen, respectively, prior to
alfacalcidol therapy. All patients received
alfacalcidol orally for at least one month. The dosage of
alfacalcidol ranged from 0.25 to 10 micrograms/day, and the medicine was administrated intermittently when the dosage exceeded 6 micrograms/day to prevent
hypercalcemia. The therapeutic effectiveness of
alfacalcidol was evaluated according to a criteria by Koeffler (
Cancer Treat Rep 69: 1399, 1985) with minor modifications. Three patients (PASA,
RAEB, CMML) showed partial response, 3 (
RAEB,
RAEB in T, AML-M4) minor response and rest of the patients did not respond. The hematological improvement of 6 responders was transient (from 1 to 2 months), however, one patient (PASA) is still responding to
alfacalcidol therapy (0.25 microgram/day) for over 12 months. The dysplastic features of hemopoietic cells in the bone marrow showed no noticeable change during the hematological improvement in these responders, suggesting the improvement was obtained as a result of alteration in the proliferation or differentiation of neoplastic clone. None of 13 patients developed
hypercalcemia. One patient (AML-M4) became excitable on high dose
alfacalcidol (10 micrograms/day). In conclusion,
alfacalcidol therapy is effective in some patients with MDS or
leukemias and appears worthy especially in the clinical state in which
chemotherapy is not indicated.