Analysis of the premalignant stages of Barrett's oesophagus through to XXXX by comparative genomic hybridization.

@entity1 @entity354 @entity258 @entity420 @entity1141
OBJECTIVES: Barrett's oesophagus is a pre-neoplastic lesion, which develops as a complication of chronic @entity354 and predisposes the @entity1 to @entity420 . Our aim was to characterize karyotypic changes that may occur during the progression of Barrett's metaplasia through @entity258 and high-grade @entity1141 to @entity420 . METHODS: The technique of comparative genomic hybridization was used to characterize genome-wide changes in biopsies from @entity1 with @entity258 , @entity258 plus high-grade @entity1141 , high-grade @entity1141 or @entity420 . Both fresh and archival material was examined. RESULTS: Comparative genomic hybridization revealed a large amount of widespread chromosome instability at the high-grade @entity1141 stage. No significant chromosome changes were detectable by comparative genomic hybridization in @entity1 with @entity258 . Karyotypic changes in the @entity420 @entity1 were more specific than those found in the high-grade @entity1141 @entity1 . Chromosome 4 was amplified most often in high-grade @entity1141 and chromosome 8q was amplified most frequently in the @entity420 . CONCLUSIONS: These data demonstrate that high-grade @entity1141 is the stage exhibiting widespread chromosome instability, which is detectable by comparative genomic hybridization. This instability is undetectable in @entity258 . The chromosome variation seen at high-grade @entity1141 may be the source of more specific karyotypes that progress to @entity420 . Importantly, we have identified chromosome 4 amplification as being heavily involved in the initiation of Barrett's progression. Specific chromosome changes (4 and 8q) may represent important regions on which to focus attention in future studies, with a view to identifying diagnostic markers.
