Systematic screening at diagnosis of -5/del(5)(q31), -7, or chromosome 8 aneuploidy by interphase fluorescence in situ hybridization in 110 acute myelocytic leukemia and high-risk myelodysplastic syndrome patients: concordances and discrepancies with conventional cytogenetics.
To assess the contribution of interphase fluorescence in situ hybridization (I-FISH) toward the detection of recurring unbalanced chromosomal anomalies at diagnosis, a systematic screening of -5/del(5)(q31), -7, and chromosome 8 aneuploidy was performed on 110 patients with acute myelocytic leukemia or high-risk myelodysplastic syndrome. We searched for monosomy 5/del(5q) by one-color I-FISH with a probe specific for the 5q31 region and for -7/8 by dual-color I-FISH with centromeric probes for chromosomes 7 and 8. Discrepancies between conventional cytogenetics (CC) and I-FISH were observed in 8 of the 110 patients (7.3%). For -5/del(5)(q31), a discordance was observed in two patients with complex abnormalities involving chromosome 5. Whereas no discordance was observed for -7, I-FISH detected a trisomy 7 unnoticed by CC in two cases. In six patients, I-FISH revealed a chromosome 8 aneuploidy not detected by CC. Our results illustrate that, when using this specific set of probes, I-FISH is of special interest for the detection of minor clones with chromosome 8 aneuploidy, breakpoint assessment, and sequence identification (markers). Also, to avoid misinterpretations, I-FISH should not be used alone at disease presentation, particularly in cases complex changes that have clearly established prognostic significance.
Beyer
Valérie
V
Unité de cytogénétique du cancer, Service de génétique médicale, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne CH-1011, Switzerland.
Castagné
Chantal
C
Mühlematter
Dominique
D
Parlier
Valérie
V
Gmür
Jürg
J
Hess
Urs
U
Kovacsovics
Tibor
T
Meyer-Monard
Sandrine
S
Tichelli
André
A
Tobler
Andreas
A
Jacky
Emanuel
E
Schanz
Urs
U
Bargetzi
Mario
M
Hagemeijer
Anne
A
de Witte
Theo
T
van Melle
Guy
G
Jotterand
Martine
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000782:Aneuploidy; D002872:Chromosome Deletion; D002895:Chromosomes, Human, Pair 5 / Q000235:genetics*; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D020732:Cytogenetic Analysis; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000235:genetics*; D014314:Trisomy