Wilms' tumor is the most frequent renal neoplasm in children, but little has been known about the genetic alterations that determine its prognosis. In August 3 The Lancet Yong-Jie Lu and colleagues at the Institute of Cancer Research and the Royal Marsden Hospital NHS Trust, Sutton, UK, show that expression profiles of chromosome 1q can predict relapses in Wilms' tumor (Lancet 2002, 360:385-386).

Lu et al. analyzed 18 cases of Wilms' tumor with favorable histological findings using a novel gene-expression profiling method (comparative expressed sequence hybridization — CESH) that targets individual chromosomes. They observed that relative overexpression of genes on the long arm of chromosome 1 was shown in all tumors that subsequently relapsed but in none of those from patients in remission.

This finding suggests that CESH analysis can be used to rapidly screen for chromosomal regions that carry genes whose differential expression is important in...