To annotate inter-tumor heterogeneity of enhancer usage, we ranked ARBS based on detected peaks in the fraction of tumors analyzed, revealing an unexpected high level of AR enhancer heterogeneity between tumors (Fig. 1a), with typical AR-inducible genes FKBP5 and KLK3 regulated by highly ranked ARBS enhancers 129 and 343 (enhID, Source Data), respectively. Here, KLK3 is linked to neoplasm.