title: Trisomy 4 as the sole cytogenetic abnormality in a patient with T-cell acute lymphoblastic leukemia.
abstract: Trisomies as sole cytogenetic abnormalities are extremely rare in acute lymphoblastic leukemia (ALL). We describe here the clinical features and immunophenotyping, cytogenetic, and fluorescence in situ hybridization (FISH) findings in a T-cell ALL patient with trisomy 4 as the sole cytogenetic abnormality. The leukemic clone was positive for CD2, CD7, CD34, and terminal deoxynucleotidyl transferase (TdT); CD13 was weakly expressed. Data on the tracking of the leukemic clone with immunophenotyping, cytogenetic, and FISH studies are discussed. The present case is compared with the three previous reported cases of trisomy 4 in ALL. Due to the rarity of this cytogenetic abnormality, its prognostic significance in ALL remains unclear.
authors.affiliation: Department of Medical Oncology and Hematology, Princess Margaret Hospital-University Health Network, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada. vikas.gupta@uhn.on.ca
authors.forename: Vikas
authors.initials: V
authors.lastname: Gupta
authors.forename: Kathy
authors.initials: K
authors.lastname: Chun
mesh_terms: D000293:Adolescent; D002869:Chromosome Aberrations; D002894:Chromosomes, Human, Pair 4; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000235:genetics*; D008297:Male; D011379:Prognosis; D014314:Trisomy