SLIT2 and Wilms tumor: The frequency of relapse in Wilms' tumours with SLIT2 methylation was similar to that without SLIT2 methylation (21% (three out of 14) and 17% (four out of 23), respectively), and there was no significant association between SLIT2 methylation and advanced stage tumours (the frequency of stage 3 and 4 tumours in the SLIT2 methylated and unmethylated groups was 45% (five out of 11) and 63% (12 out of 19), respectively).