Masked Deficit of Vitamin B12in a Turkish Girl with Thalassemia

A 12-year-old girl with acute promyelocytic leukemia has been treated with conventional chemotherapy. The patient remained in complete remission for a year when the first bone marrow relapse occurred. Since reinduction chemotherapy was rejected by the parents, an alternative treatment with oral all-trans retinoic acid was administered. A second complete remission was achieved within 100 days. After 14 months a second bone marrow relapse occurred. AM-trans retinoic acid and the combination with interferon-a failed.