For instance, about 20 % of HGPIN lesion harbour TMPRSS2-ERG fusion gene, which is a common molecular abnormality detectable in about 50 % of prostate cancers [16] as well as aneuploidy which is more frequent in HGPIN than benign prostate tissue, although somewhat less than seen in some invasive carcinomas [9]. The gene discussed is ERG; the disease is invasive carcinoma.