Chromosome 1q expression profiling and relapse in Wilmsʹ tumour

Gene-expression patterns have proved useful for tumour classification and prediction of prognosis. We investigated a new gene-expression profiling method that targets individual chromosomes—comparative expressed sequence hybridisation (CESH)—to establish if any expression pattern was associated with relapse, and if this pattern could accurately predict outcome. We studied 18 cases of Wilmsʹ tumour with favourable histological findings. Relative overexpression of genes on the long arm of chromosome 1 was shown in all tumours that subsequently relapsed but in none of those from patients in remission (odds ratio 357, 95% CI 6•4–19 960). This finding shows the value of CESH analysis to rapidly screen for chromosomal regions that carry genes whose differential expression is important in establishment of tumour behaviour.