Cancer Genetics and Cytogenetics 142 (2003) 83–85 0165-4608/03/$ – see front matter © 2003 Elsevier Science Inc. All rights reserved. doi:10.1016/S0165-4608(02)00800-2 Short communication Trisomy X in Philadelphia chromosome–negative cells during the course of Philadelphia chromosome–positive chronic myelocytic leukemia Asahi Hishida a,* , Kazuhito Yamamoto a , Tadashi Matsushita a , Mitsune Tanimoto b , Hidehiko Saito c , Nobuhiko Emi a a First Department of Internal Medicine, Nagoya University School of Medicine, Nagoya, Japan b Second Department of Internal Medicine, Okayama University School of Medicine, Okayama, Japan c Nagoya National Hospital, Nagoya, Japan Received 17 July 2002; received in revised form 9 September 2002; accepted 10 September 2002 Abstract A Philadelphia chromosome-negative (Ph - ) clone with trisomy X appeared in the bone marrow cells from a patient with Ph + chronic myelocytic leukemia in the chronic phase after hydroxyurea and interferon-  treatment. © 2003 Elsevier Science Inc. All rights reserved. 1. Introduction Philadelphia chromosome–positive (Ph + ) chronic myelo- cytic leukemia (CML) often requires additional chromosome anomalies such as trisomy 8, duplication of Ph, and an iso- chromosome of the long arm of chromosome 17 when CML patients enter the accelerated or blastic phase [1,2]. Three dif- ferent groups have reported the observation of Ph - cells with trisomy 8 in patients with Ph + CML in the chronic phase dur- ing the course of interferon- (IFN-) therapy [3–5]. We present the case of a patient with Ph + CML who acquired a Ph - plus X clone during the course of IFN therapy. 2. Case report and results A 21-year-old female patient complained of gingival bleed- ing in December 1996. Blood indices were as follows: hemo- globin, 12.3 g/dL; white blood cells (WBC), 33,000/mm 3 (45% neutrophils, 8% eosinophils, 10% basophils, 10% mono- cytes, 16% lymphocytes, 1% atypical lymphocytes, 1% meta- myelocytes, 8% myelocytes, 1% blasts); and platelets, 72,600/ mm 3 . Bone marrow aspiration was performed, and the speci- men showed hypercellularity with myelocytic series hyper- plasia. A diagnosis of CML was made. The patient was treated with hydroxyurea (1,500 mg/day) until March 1997, at which time blood indices showed Hb, 13.0 g/dL; WBC, 5800/mm 3 (30% neutrophils, 3% eosinophils, 4% basophils, 11% monocytes, 51% lymphocytes, 1% metamyelocytes); and platelets, 300,000/mm 3 . Treatment with recombinant IFN- (3  10 6 units/day) was started. In March 2000, severe pancytopenia developed. Blood indices were as follows: Hb, 9.3 g/dL; WBC, 1900/mm 3 (neutrophils 200/mm 3 ); and platelets 5000/mm 3 . Treatment was immediately discontinued, but the pancytopenia per- sisted, and the patient required repeated blood transfusions. On June 16, 2000, the patient was admitted to the hospi- tal for dental infection. Blood indices on admission were as follows: Hb, 7.1 g/dL; WBC, 1800/mm 3 (neutrophils 60/mm 3 ); and platelets, 38,000/mm 3 . Bone marrow aspiration was performed, and the specimen showed severe hypocellular bone marrow consisting only of lymphocytes and a few plasma cells. A bone marrow biopsy was also performed, and the specimen showed fatty marrow (with no fibrosis). On June 27, 2000, granulocyte colony stimulating factor (G-CSF) subcutaneous injections were started to prevent a fatal infection. On August 18, 2000, immunosuppressive therapy with cyclosporin A (CyA) (6 mg/kg/day) was started. The patient’s bone marrow recovered gradually, and blood transfusions were discontinued. Chromosome analyses were performed on G-banded meta- phase chromosomes prepared from bone marrow cells in December 1996; February 1998; August, September, and October 2000; November 2001; and January 2002. The re- sults are shown in Table 1. Chromosome analyses during the chronic phase showed that all the cells were Ph + before the patient developed bone marrow aplasia, after which the Ph + clone disappeared, and a normal clone and one unexpected clone with trisomy X * Corresponding author. Tel.: +81-52-744-2145; fax: +81-52-744-2161. E-mail address: a-hishi@med.nagoya-u.ac.jp (A. Hishida).