A systematic investigation in 9,624 tumors (33 cancer types) found that fusions were the sole driver in >1% of cancers, contributed to the development of 16.5% of cancer cases, and were likely to be druggable in 6%, with further potential for treatment with immunotherapy.41 The most highly recurrent fusion was TMPRSS2-ERG, observed in 38% of cases of prostate adenocarcinoma. This evidence concerns the gene ERG and cancer.