Acute promyelocytic leukemia with t(15;17) and two previously unreported additional cytogenetic abnormalities

Excerpt

A 40-year-old alcoholic man with a past medical history of hypertension presented to the emergency department with progressive fatigue and dyspnea on exertion for about 3 months. Physical examination was remarkable only for pale conjunctiva. He had pancytopenia (white blood cells 0.5 × 10⁹/L, hemoglobin 6.3 g/dL and platelets 31 × 10⁹/L) and a normal coagulation panel. A peripheral blood smear showed pancytopenia with unremarkable morphology of the few existing circulating white cells. Other routine laboratory tests were within normal limits. With a presumptive diagnosis of alcohol-induced bone marrow suppression, he received filgrastim injections (300 mcg daily) for 3 days until his WBC count reached 10.4 × 10⁹/L. A peripheral blood smear at this time revealed 63 % immature cells, many of which contained Auer rods. A bone marrow aspiration and biopsy was performed. The bone marrow was packed (95 % cellularity) with immature myeloid cells containing occasional Auer rods that stained positively for CD117 and myeloperoxidase (MPO) and negatively for CD34 and HLA-DR. Cytogenetic analysis showed a complex male karyotype with 46,XY, t(1;10)(p22;q24), t(2;8)(p21;q22), t(15;17)(q22;q21) in 19/20 analyzed cells. Reverse transcriptase polymerase chain reaction was positive for the PML-RARα transcript, confirming a diagnosis of acute promyelocytic leukemia (APL) with additional cytogenetic abnormalities. Induction therapy was initiated with all-trans retinoic acid (ATRA; 45 mg/m² per day in two divided doses orally) and idarubicin (12 mg/m² intravenously per day) based on the AIDA protocol [1]. The patient completed an uncomplicated course of induction therapy, followed by consolidation therapy with cytarabine (100 mg/m² intravenously per day), idarubicin (12 mg/m² intravenously per day) and ATRA (45 mg/m² per day in two divided doses orally), and achieved complete remission. …