The Kattan and Steyerberg nomograms outperformed other models for predicting the probability of insignificant disease in patients with Gleason score ≤6 prostate cancers diagnosed upon extended transrectal biopsy with ≥10 cores (n = 370). All nomograms were more accurate in identifying significant rather than insignificant disease and performed better in patients with posterior–basal tumours than in those with cancers located in the anterior and apical prostate.