title: Fluorescence in situ hybridization improves the detection of 5q31 deletion in myelodysplastic syndromes without cytogenetic evidence of 5q-.
abstract: BACKGROUND
  More than 50% of patients with myelodysplastic syndromes present cytogenetic aberrations at diagnosis. Partial or complete deletion of the long arm of chromosome 5 is the most frequent abnormality. The aim of this study was to apply fluorescence in situ hybridization of 5q31 in patients diagnosed with de novo myelodysplastic syndromes in whom conventional banding cytogenetics study had shown a normal karyotype, absence of metaphases or an abnormal karyotype without evidence of del(5q).
  
  
  METHODS
  We performed fluorescence in situ hybridization of 5q31 in 716 patients, divided into two groups: group A patients (n=637) in whom the 5q deletion had not been detected at diagnosis by conventional banding cytogenetics and group B patients (n=79), in whom cytogenetic analysis had revealed the 5q deletion (positive control group).
  
  
  RESULTS
  In group A (n=637), the 5q deletion was detected by fluorescence in situ hybridization in 38 cases (5.96%). The majority of positive cases were diagnosed as having the 5q- syndrome. The deletion was mainly observed in cases in which the cytogenetics study had shown no metaphases or an aberrant karyotype with chromosome 5 involved. In group B (n=79), the 5q deletion had been observed by cytogenetics and was confirmed to be present in all cases by fluorescence in situ hybridization of 5q31.
  
  
  CONCLUSIONS
  Fluorescence in situ hybridization of 5q31 detected the 5q deletion in 6% of cases without clear evidence of del(5q) by conventional banding cytogenetics. We suggest that fluorescence in situ hybridization of 5q31 should be performed in cases of a suspected '5q- syndrome' and/or if the cytogenetic study shows no metaphases or an aberrant karyotype with chromosome 5 involved (no 5q- chromosome).
authors.affiliation: Laboratori de, Citogenètica i Biologia Molecular, Servei de Patologia, IMAS, GRETNHE, IMIM-Hospital del Mar, Barcelona.
authors.forename: Mar
authors.initials: M
authors.lastname: Mallo
authors.forename: Leonor
authors.initials: L
authors.lastname: Arenillas
authors.forename: Blanca
authors.initials: B
authors.lastname: Espinet
authors.forename: Marta
authors.initials: M
authors.lastname: Salido
authors.forename: Jesús M
authors.initials: JM
authors.lastname: Hernández
authors.forename: Eva
authors.initials: E
authors.lastname: Lumbreras
authors.forename: Mónica
authors.initials: M
authors.lastname: del Rey
authors.forename: Eva
authors.initials: E
authors.lastname: Arranz
authors.forename: Soraya
authors.initials: S
authors.lastname: Ramiro
authors.forename: Patricia
authors.initials: P
authors.lastname: Font
authors.forename: Olga
authors.initials: O
authors.lastname: González
authors.forename: Mónica
authors.initials: M
authors.lastname: Renedo
authors.forename: José
authors.initials: J
authors.lastname: Cervera
authors.forename: Esperanza
authors.initials: E
authors.lastname: Such
authors.forename: Guillermo F
authors.initials: GF
authors.lastname: Sanz
authors.forename: Elisa
authors.initials: E
authors.lastname: Luño
authors.forename: Carmen
authors.initials: C
authors.lastname: Sanzo
authors.forename: Miriam
authors.initials: M
authors.lastname: González
authors.forename: María José
authors.initials: MJ
authors.lastname: Calasanz
authors.forename: José
authors.initials: J
authors.lastname: Mayans
authors.forename: Carlos
authors.initials: C
authors.lastname: García-Ballesteros
authors.forename: Victoria
authors.initials: V
authors.lastname: Amigo
authors.forename: Rosa
authors.initials: R
authors.lastname: Collado
authors.forename: Isabel
authors.initials: I
authors.lastname: Oliver
authors.forename: Félix
authors.initials: F
authors.lastname: Carbonell
authors.forename: Encarna
authors.initials: E
authors.lastname: Bureo
authors.forename: Andrés
authors.initials: A
authors.lastname: Insunza
authors.forename: Lucrecia
authors.initials: L
authors.lastname: Yañez
authors.forename: María José
authors.initials: MJ
authors.lastname: Muruzabal
authors.forename: Elena
authors.initials: E
authors.lastname: Gómez-Beltrán
authors.forename: Rafael
authors.initials: R
authors.lastname: Andreu
authors.forename: Pilar
authors.initials: P
authors.lastname: León
authors.forename: Valle
authors.initials: V
authors.lastname: Gómez
authors.forename: Angeles
authors.initials: A
authors.lastname: Sanz
authors.forename: Natalia
authors.initials: N
authors.lastname: Casasola
authors.forename: Esperanza
authors.initials: E
authors.lastname: Moreno
authors.forename: Adrián
authors.initials: A
authors.lastname: Alegre
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Martín
authors.forename: Carmen
authors.initials: C
authors.lastname: Pedro
authors.forename: Sergi
authors.initials: S
authors.lastname: Serrano
authors.forename: Lourdes
authors.initials: L
authors.lastname: Florensa
authors.forename: Francesc
authors.initials: F
authors.lastname: Solé
mesh_terms: D016022:Case-Control Studies; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002895:Chromosomes, Human, Pair 5 / Q000235:genetics*; D003582:Cytogenetics / Q000379:methods; D005260:Female; D017353:Gene Deletion; D006405:Hematology / Q000379:methods; D006801:Humans; D006824:Hybridization, Genetic; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D008677:Metaphase; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000235:genetics*