title: FLAG-induced remission in a patient with acute mast cell leukemia (MCL) exhibiting t(7;10)(q22;q26) and KIT D816H.
abstract: Mast cell leukemia (MCL) is a life-threatening disease associated with high mortality and drug-resistance. Only few patients survive more than 12 months. We report on a 55-year-old female patient with acute MCL diagnosed in May 2012. The disease was characterized by a rapid increase in white blood cells and mast cells (MC) in the peripheral blood, and a rapid increase of serum tryptase levels. The KIT D816H mutation was detected in the blood and bone marrow (BM). Induction chemotherapy with high-dose ARA-C and fludarabine (FLAG) was administered. Unexpectedly, the patient entered a hematologic remission with almost complete disappearance of neoplastic MC and a decrease of serum tryptase levels to normal range after 2 cycles of FLAG. Consecutively, the patient was prepared for allogeneic stem cell transplantation. However, shortly after the third cycle of FLAG, tryptase levels increased again, immature MC appeared in the blood, and the patient died from cerebral bleeding. Together, this case shows that intensive chemotherapy regimens, like FLAG, may induce remission in acute MCL. However, treatment responses are short-lived and the overall outcome remains dismal in these patients. We propose to separate this acute type of MCL from more subacute or chronic variants of MCL.
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria ; Ludwig Boltzmann Cluster Oncology (LB-CO), Medical University of Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Valent
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.
authors.forename: Katharina
authors.initials: K
authors.lastname: Blatt
authors.affiliation: Ludwig Boltzmann Cluster Oncology (LB-CO), Medical University of Vienna, Austria.
authors.forename: Gregor
authors.initials: G
authors.lastname: Eisenwort
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria ; Ludwig Boltzmann Cluster Oncology (LB-CO), Medical University of Vienna, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Herrmann
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria ; Ludwig Boltzmann Cluster Oncology (LB-CO), Medical University of Vienna, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Cerny-Reiterer
authors.affiliation: Department of Laboratory Medicine, Medical University of Vienna, Austria.
authors.forename: Renate
authors.initials: R
authors.lastname: Thalhammer
authors.affiliation: Department of Clinical Pathology, Medical University of Vienna, Austria.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Müllauer
authors.affiliation: Department of Laboratory Medicine, Medical University of Vienna, Austria.
authors.forename: Gregor
authors.initials: G
authors.lastname: Hoermann
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.
authors.forename: Irina
authors.initials: I
authors.lastname: Sadovnik
authors.affiliation: Department of Laboratory Medicine, Medical University of Vienna, Austria.
authors.forename: Ilse
authors.initials: I
authors.lastname: Schwarzinger
authors.affiliation: Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria ; Ludwig Boltzmann Cluster Oncology (LB-CO), Medical University of Vienna, Austria.
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Sperr
authors.affiliation: Department of Laboratory Medicine, Medical University of Vienna, Austria.
authors.forename: Christine
authors.initials: C
authors.lastname: Mannhalter
authors.affiliation: Institute of Pathology, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Horny
keywords: Chemotherapy; FLAG; KIT; Mast cell leukemia; Mast cells