Although the best performance of the pathway-based prediction models (e.g. 92.2% prediction accuracy was obtained for Singh testing data using 28 genes in insulin signalling pathway identified by PLM) is slightly worse than the best prediction accuracy based solely on the top genes (e.g. 94.1% prediction accuracy was obtained for the same data using 17 the most significantly expressed genes), the set of significantly enriched pathways showing the strongest correlation to prostate tumour expression patterns is likely to be of greater biological interest. The gene discussed is INS; the disease is prostate neoplasm.